package org.apache.maven.model.merge;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import java.io.ObjectStreamException;
import java.util.AbstractList;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Properties;

import org.apache.maven.model.Activation;
import org.apache.maven.model.Build;
import org.apache.maven.model.BuildBase;
import org.apache.maven.model.CiManagement;
import org.apache.maven.model.ConfigurationContainer;
import org.apache.maven.model.Contributor;
import org.apache.maven.model.Dependency;
import org.apache.maven.model.DependencyManagement;
import org.apache.maven.model.DeploymentRepository;
import org.apache.maven.model.Developer;
import org.apache.maven.model.DistributionManagement;
import org.apache.maven.model.Exclusion;
import org.apache.maven.model.Extension;
import org.apache.maven.model.FileSet;
import org.apache.maven.model.InputLocation;
import org.apache.maven.model.IssueManagement;
import org.apache.maven.model.License;
import org.apache.maven.model.MailingList;
import org.apache.maven.model.Model;
import org.apache.maven.model.ModelBase;
import org.apache.maven.model.Notifier;
import org.apache.maven.model.Organization;
import org.apache.maven.model.Parent;
import org.apache.maven.model.PatternSet;
import org.apache.maven.model.Plugin;
import org.apache.maven.model.PluginConfiguration;
import org.apache.maven.model.PluginContainer;
import org.apache.maven.model.PluginExecution;
import org.apache.maven.model.PluginManagement;
import org.apache.maven.model.Prerequisites;
import org.apache.maven.model.Profile;
import org.apache.maven.model.Relocation;
import org.apache.maven.model.ReportPlugin;
import org.apache.maven.model.ReportSet;
import org.apache.maven.model.Reporting;
import org.apache.maven.model.Repository;
import org.apache.maven.model.RepositoryBase;
import org.apache.maven.model.RepositoryPolicy;
import org.apache.maven.model.Resource;
import org.apache.maven.model.Scm;
import org.apache.maven.model.Site;
import org.codehaus.plexus.util.xml.Xpp3Dom;

/**
 * This is a hand-crafted prototype of the default model merger that should eventually be generated by Modello by a new
 * Java plugin. Code structure to merge source (read-only) object into the target object is:<ul>
 * <li><code>merge<i>Classname</i>( <i>Classname</i> target, <i>Classname</i> source, boolean sourceDominant,
 * Map&lt;Object, Object&gt; context )</code> for each model class</li>
 * <li><code>merge<i>Classname</i>_<i>FieldName</i>( <i>Classname</i> target, <i>Classname</i> source, boolean
 * sourceDominant, Map&lt;Object, Object&gt; context )</code> for each field of each model class</li>
 * <li><code>Object get<i>Classname</i>Key( <i>Classname</i> <i>classname</i> )</code>
 * for each class that is used in a list</li>
 * </ul>
 * Code is written like it could be generated, with default behaviour to be overridden when necessary.
 * This is particularly the case for <code>Object get<i>Classname</i>Key( <i>Classname</i> <i>classname</i> )</code>
 * method, which by default return the object itself and is expected to be overridden to calculate better suited key
 * value.
 *
 * @author Benjamin Bentmann
 */
@SuppressWarnings( { "checkstyle:methodname" } )
public class ModelMerger
{

    /**
     * Merges the specified source object into the given target object.
     *
     * @param target The target object whose existing contents should be merged with the source, must not be
     *            <code>null</code>.
     * @param source The (read-only) source object that should be merged into the target object, may be
     *            <code>null</code>.
     * @param sourceDominant A flag indicating whether either the target object or the source object provides the
     *            dominant data.
     * @param hints A set of key-value pairs that customized merger implementations can use to carry domain-specific
     *            information along, may be <code>null</code>.
     */
    public void merge( Model target, Model source, boolean sourceDominant, Map<?, ?> hints )
    {
        Objects.requireNonNull( target, "target cannot be null" );

        if ( source == null )
        {
            return;
        }

        Map<Object, Object> context = new HashMap<>();
        if ( hints != null )
        {
            context.putAll( hints );
        }

        mergeModel( target, source, sourceDominant, context );
    }

    protected void mergeModel( Model target, Model source, boolean sourceDominant, Map<Object, Object> context )
    {
        mergeModelBase( target, source, sourceDominant, context );

        mergeModel_ChildProjectUrlInheritAppendPath( target, source, sourceDominant, context );
        mergeModel_ModelVersion( target, source, sourceDominant, context );
        mergeModel_Parent( target, source, sourceDominant, context );
        mergeModel_GroupId( target, source, sourceDominant, context );
        mergeModel_ArtifactId( target, source, sourceDominant, context );
        mergeModel_Version( target, source, sourceDominant, context );
        mergeModel_Packaging( target, source, sourceDominant, context );
        mergeModel_Name( target, source, sourceDominant, context );
        mergeModel_Description( target, source, sourceDominant, context );
        mergeModel_Url( target, source, sourceDominant, context );
        mergeModel_InceptionYear( target, source, sourceDominant, context );
        mergeModel_Organization( target, source, sourceDominant, context );
        mergeModel_Licenses( target, source, sourceDominant, context );
        mergeModel_MailingLists( target, source, sourceDominant, context );
        mergeModel_Developers( target, source, sourceDominant, context );
        mergeModel_Contributors( target, source, sourceDominant, context );
        mergeModel_IssueManagement( target, source, sourceDominant, context );
        mergeModel_Scm( target, source, sourceDominant, context );
        mergeModel_CiManagement( target, source, sourceDominant, context );
        mergeModel_Prerequisites( target, source, sourceDominant, context );
        mergeModel_Build( target, source, sourceDominant, context );
        mergeModel_Profiles( target, source, sourceDominant, context );
    }

    protected void mergeModel_ModelVersion( Model target, Model source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        String src = source.getModelVersion();
        if ( src != null )
        {
            if ( sourceDominant || target.getModelVersion() == null )
            {
                target.setModelVersion( src );
                target.setLocation( "modelVersion", source.getLocation( "modelVersion" ) );
            }
        }
    }

    protected void mergeModel_Parent( Model target, Model source, boolean sourceDominant, Map<Object, Object> context )
    {
        Parent src = source.getParent();
        if ( src != null )
        {
            Parent tgt = target.getParent();
            if ( tgt == null )
            {
                tgt = new Parent();
                tgt.setRelativePath( null );
                target.setParent( tgt );
            }
            mergeParent( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeModel_GroupId( Model target, Model source, boolean sourceDominant,
                                       Map<Object, Object> context )
    {
        String src = source.getGroupId();
        if ( src != null )
        {
            if ( sourceDominant || target.getGroupId() == null )
            {
                target.setGroupId( src );
                target.setLocation( "groupId", source.getLocation( "groupId" ) );
            }
        }
    }

    protected void mergeModel_ArtifactId( Model target, Model source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        String src = source.getArtifactId();
        if ( src != null )
        {
            if ( sourceDominant || target.getArtifactId() == null )
            {
                target.setArtifactId( src );
                target.setLocation( "artifactId", source.getLocation( "artifactId" ) );
            }
        }
    }

    protected void mergeModel_ChildProjectUrlInheritAppendPath( Model target, Model source, boolean sourceDominant,
                                                                Map<Object, Object> context )
    {
        String src = source.getChildProjectUrlInheritAppendPath();
        if ( src != null )
        {
            if ( sourceDominant || target.getChildProjectUrlInheritAppendPath() == null )
            {
                target.setChildProjectUrlInheritAppendPath( src );
                target.setLocation( "child.project.url.inherit.append.path",
                                    source.getLocation( "child.project.url.inherit.append.path" ) );
            }
        }
    }

    protected void mergeModel_Version( Model target, Model source, boolean sourceDominant,
                                       Map<Object, Object> context )
    {
        String src = source.getVersion();
        if ( src != null )
        {
            if ( sourceDominant || target.getVersion() == null )
            {
                target.setVersion( src );
                target.setLocation( "version", source.getLocation( "version" ) );
            }
        }
    }

    protected void mergeModel_Packaging( Model target, Model source, boolean sourceDominant,
                                         Map<Object, Object> context )
    {
        String src = source.getPackaging();
        if ( src != null )
        {
            if ( sourceDominant || target.getPackaging() == null )
            {
                target.setPackaging( src );
                target.setLocation( "packaging", source.getLocation( "packaging" ) );
            }
        }
    }

    protected void mergeModel_Name( Model target, Model source, boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getName();
        if ( src != null )
        {
            if ( sourceDominant || target.getName() == null )
            {
                target.setName( src );
                target.setLocation( "name", source.getLocation( "name" ) );
            }
        }
    }

    protected void mergeModel_Description( Model target, Model source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getDescription();
        if ( src != null )
        {
            if ( sourceDominant || target.getDescription() == null )
            {
                target.setDescription( src );
                target.setLocation( "description", source.getLocation( "description" ) );
            }
        }
    }

    protected void mergeModel_Url( Model target, Model source, boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getUrl() == null )
            {
                target.setUrl( src );
                target.setLocation( "url", source.getLocation( "url" ) );
            }
        }
    }

    protected void mergeModel_InceptionYear( Model target, Model source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getInceptionYear();
        if ( src != null )
        {
            if ( sourceDominant || target.getInceptionYear() == null )
            {
                target.setInceptionYear( src );
                target.setLocation( "inceptionYear", source.getLocation( "inceptionYear" ) );
            }
        }
    }

    protected void mergeModel_Organization( Model target, Model source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        Organization src = source.getOrganization();
        if ( src != null )
        {
            Organization tgt = target.getOrganization();
            if ( tgt == null )
            {
                tgt = new Organization();
                target.setOrganization( tgt );
            }
            mergeOrganization( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeModel_Licenses( Model target, Model source, boolean sourceDominant,
                                        Map<Object, Object> context )
    {
        target.setLicenses( merge( target.getLicenses(), source.getLicenses(),
                                    sourceDominant, new LicenseKeyComputer() ) );
    }

    protected void mergeModel_MailingLists( Model target, Model source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        target.setMailingLists( merge( target.getMailingLists(), source.getMailingLists(),
                                       sourceDominant, new MailingListKeyComputer() ) );
    }

    protected void mergeModel_Developers( Model target, Model source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        target.setDevelopers( merge( target.getDevelopers(), source.getDevelopers(),
                sourceDominant, new DeveloperKeyComputer() ) );
    }

    protected void mergeModel_Contributors( Model target, Model source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        target.setContributors( merge( target.getContributors(), source.getContributors(),
                sourceDominant, new ContributorKeyComputer() ) );
    }

    protected void mergeModel_IssueManagement( Model target, Model source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        IssueManagement src = source.getIssueManagement();
        if ( src != null )
        {
            IssueManagement tgt = target.getIssueManagement();
            if ( tgt == null )
            {
                tgt = new IssueManagement();
                target.setIssueManagement( tgt );
            }
            mergeIssueManagement( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeModel_Scm( Model target, Model source, boolean sourceDominant, Map<Object, Object> context )
    {
        Scm src = source.getScm();
        if ( src != null )
        {
            Scm tgt = target.getScm();
            if ( tgt == null )
            {
                tgt = new Scm();
                tgt.setTag( null );
                target.setScm( tgt );
            }
            mergeScm( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeModel_CiManagement( Model target, Model source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        CiManagement src = source.getCiManagement();
        if ( src != null )
        {
            CiManagement tgt = target.getCiManagement();
            if ( tgt == null )
            {
                tgt = new CiManagement();
                target.setCiManagement( tgt );
            }
            mergeCiManagement( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeModel_Prerequisites( Model target, Model source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        Prerequisites src = source.getPrerequisites();
        if ( src != null )
        {
            Prerequisites tgt = target.getPrerequisites();
            if ( tgt == null )
            {
                tgt = new Prerequisites();
                tgt.setMaven( null );
                target.setPrerequisites( tgt );
            }
            mergePrerequisites( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeModel_Build( Model target, Model source, boolean sourceDominant, Map<Object, Object> context )
    {
        Build src = source.getBuild();
        if ( src != null )
        {
            Build tgt = target.getBuild();
            if ( tgt == null )
            {
                tgt = new Build();
                target.setBuild( tgt );
            }
            mergeBuild( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeModel_Profiles( Model target, Model source, boolean sourceDominant,
                                        Map<Object, Object> context )
    {
        target.setProfiles( merge( target.getProfiles(), source.getProfiles(),
                sourceDominant, new ProfileKeyComputer() ) );
    }

    protected void mergeModelBase( ModelBase target, ModelBase source, boolean sourceDominant,
                                   Map<Object, Object> context )
    {
        mergeModelBase_DistributionManagement( target, source, sourceDominant, context );
        mergeModelBase_Modules( target, source, sourceDominant, context );
        mergeModelBase_Repositories( target, source, sourceDominant, context );
        mergeModelBase_PluginRepositories( target, source, sourceDominant, context );
        mergeModelBase_Dependencies( target, source, sourceDominant, context );
        mergeModelBase_Reporting( target, source, sourceDominant, context );
        mergeModelBase_DependencyManagement( target, source, sourceDominant, context );
        mergeModelBase_Properties( target, source, sourceDominant, context );
    }

    protected void mergeModelBase_Modules( ModelBase target, ModelBase source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        List<String> src = source.getModules();
        if ( !src.isEmpty() )
        {
            List<String> tgt = target.getModules();
            List<String> merged = new ArrayList<>( tgt.size() + src.size() );
            merged.addAll( tgt );
            merged.addAll( src );
            target.setModules( merged );
        }
    }

    protected void mergeModelBase_Dependencies( ModelBase target, ModelBase source, boolean sourceDominant,
                                                Map<Object, Object> context )
    {
        target.setDependencies( merge( target.getDependencies(), source.getDependencies(),
                sourceDominant, new DependencyKeyComputer() ) );
    }

    protected void mergeModelBase_Repositories( ModelBase target, ModelBase source, boolean sourceDominant,
                                                Map<Object, Object> context )
    {
        target.setRepositories( merge( target.getRepositories(), source.getRepositories(),
                sourceDominant, new RepositoryKeyComputer() ) );
    }

    protected void mergeModelBase_PluginRepositories( ModelBase target, ModelBase source, boolean sourceDominant,
                                                      Map<Object, Object> context )
    {
        target.setPluginRepositories( merge( target.getPluginRepositories(), source.getPluginRepositories(),
                sourceDominant, new RepositoryKeyComputer() ) );
    }

    protected void mergeModelBase_DistributionManagement( ModelBase target, ModelBase source, boolean sourceDominant,
                                                          Map<Object, Object> context )
    {
        DistributionManagement src = source.getDistributionManagement();
        if ( src != null )
        {
            DistributionManagement tgt = target.getDistributionManagement();
            if ( tgt == null )
            {
                tgt = new DistributionManagement();
                target.setDistributionManagement( tgt );
            }
            mergeDistributionManagement( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeModelBase_Reporting( ModelBase target, ModelBase source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        Reporting src = source.getReporting();
        if ( src != null )
        {
            Reporting tgt = target.getReporting();
            if ( tgt == null )
            {
                tgt = new Reporting();
                target.setReporting( tgt );
            }
            mergeReporting( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeModelBase_DependencyManagement( ModelBase target, ModelBase source, boolean sourceDominant,
                                                        Map<Object, Object> context )
    {
        DependencyManagement src = source.getDependencyManagement();
        if ( src != null )
        {
            DependencyManagement tgt = target.getDependencyManagement();
            if ( tgt == null )
            {
                tgt = new DependencyManagement();
                target.setDependencyManagement( tgt );
            }
            mergeDependencyManagement( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeModelBase_Properties( ModelBase target, ModelBase source, boolean sourceDominant,
                                              Map<Object, Object> context )
    {
        Properties merged = new Properties();
        if ( sourceDominant )
        {
            merged.putAll( target.getProperties() );
            merged.putAll( source.getProperties() );
        }
        else
        {
            merged.putAll( source.getProperties() );
            merged.putAll( target.getProperties() );
        }
        target.setProperties( merged );
        target.setLocation( "properties", InputLocation.merge( target.getLocation( "properties" ),
                                                               source.getLocation( "properties" ), sourceDominant ) );
    }

    protected void mergeDistributionManagement( DistributionManagement target, DistributionManagement source,
                                                boolean sourceDominant, Map<Object, Object> context )
    {
        mergeDistributionManagement_Repository( target, source, sourceDominant, context );
        mergeDistributionManagement_SnapshotRepository( target, source, sourceDominant, context );
        mergeDistributionManagement_Site( target, source, sourceDominant, context );
        mergeDistributionManagement_Status( target, source, sourceDominant, context );
        mergeDistributionManagement_DownloadUrl( target, source, sourceDominant, context );
    }

    protected void mergeDistributionManagement_Repository( DistributionManagement target,
                                                           DistributionManagement source, boolean sourceDominant,
                                                           Map<Object, Object> context )
    {
        DeploymentRepository src = source.getRepository();
        if ( src != null )
        {
            DeploymentRepository tgt = target.getRepository();
            if ( tgt == null )
            {
                tgt = new DeploymentRepository();
                target.setRepository( tgt );
            }
            mergeDeploymentRepository( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeDistributionManagement_SnapshotRepository( DistributionManagement target,
                                                                   DistributionManagement source,
                                                                   boolean sourceDominant,
                                                                   Map<Object, Object> context )
    {
        DeploymentRepository src = source.getSnapshotRepository();
        if ( src != null )
        {
            DeploymentRepository tgt = target.getSnapshotRepository();
            if ( tgt == null )
            {
                tgt = new DeploymentRepository();
                target.setSnapshotRepository( tgt );
            }
            mergeDeploymentRepository( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeDistributionManagement_Site( DistributionManagement target, DistributionManagement source,
                                                     boolean sourceDominant, Map<Object, Object> context )
    {
        Site src = source.getSite();
        if ( src != null )
        {
            Site tgt = target.getSite();
            if ( tgt == null )
            {
                tgt = new Site();
                target.setSite( tgt );
            }
            mergeSite( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeDistributionManagement_Status( DistributionManagement target, DistributionManagement source,
                                                       boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getStatus();
        if ( src != null )
        {
            if ( sourceDominant || target.getStatus() == null )
            {
                target.setStatus( src );
                target.setLocation( "status", source.getLocation( "status" ) );
            }
        }
    }

    protected void mergeDistributionManagement_DownloadUrl( DistributionManagement target,
                                                            DistributionManagement source, boolean sourceDominant,
                                                            Map<Object, Object> context )
    {
        String src = source.getDownloadUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getDownloadUrl() == null )
            {
                target.setDownloadUrl( src );
                target.setLocation( "downloadUrl", source.getLocation( "downloadUrl" ) );
            }
        }
    }

    protected void mergeRelocation( Relocation target, Relocation source, boolean sourceDominant,
                                    Map<Object, Object> context )
    {
        mergeRelocation_GroupId( target, source, sourceDominant, context );
        mergeRelocation_ArtifactId( target, source, sourceDominant, context );
        mergeRelocation_Version( target, source, sourceDominant, context );
        mergeRelocation_Message( target, source, sourceDominant, context );
    }

    protected void mergeRelocation_GroupId( Relocation target, Relocation source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        String src = source.getGroupId();
        if ( src != null )
        {
            if ( sourceDominant || target.getGroupId() == null )
            {
                target.setGroupId( src );
                target.setLocation( "groupId", source.getLocation( "groupId" ) );
            }
        }
    }

    protected void mergeRelocation_ArtifactId( Relocation target, Relocation source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        String src = source.getArtifactId();
        if ( src != null )
        {
            if ( sourceDominant || target.getArtifactId() == null )
            {
                target.setArtifactId( src );
                target.setLocation( "artifactId", source.getLocation( "artifactId" ) );
            }
        }
    }

    protected void mergeRelocation_Version( Relocation target, Relocation source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        String src = source.getVersion();
        if ( src != null )
        {
            if ( sourceDominant || target.getVersion() == null )
            {
                target.setVersion( src );
                target.setLocation( "version", source.getLocation( "version" ) );
            }
        }
    }

    protected void mergeRelocation_Message( Relocation target, Relocation source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        String src = source.getMessage();
        if ( src != null )
        {
            if ( sourceDominant || target.getMessage() == null )
            {
                target.setMessage( src );
                target.setLocation( "message", source.getLocation( "message" ) );
            }
        }
    }

    protected void mergeDeploymentRepository( DeploymentRepository target, DeploymentRepository source,
                                              boolean sourceDominant, Map<Object, Object> context )
    {
        mergeRepository( target, source, sourceDominant, context );
        mergeDeploymentRepository_UniqueVersion( target, source, sourceDominant, context );
    }

    protected void mergeDeploymentRepository_UniqueVersion( DeploymentRepository target, DeploymentRepository source,
                                                            boolean sourceDominant, Map<Object, Object> context )
    {
        if ( sourceDominant )
        {
            target.setUniqueVersion( source.isUniqueVersion() );
            target.setLocation( "uniqueVersion", source.getLocation( "uniqueVersion" ) );
        }
    }

    protected void mergeSite( Site target, Site source, boolean sourceDominant, Map<Object, Object> context )
    {
        mergeSite_ChildSiteUrlInheritAppendPath( target, source, sourceDominant, context );
        mergeSite_Id( target, source, sourceDominant, context );
        mergeSite_Name( target, source, sourceDominant, context );
        mergeSite_Url( target, source, sourceDominant, context );
    }

    protected void mergeSite_ChildSiteUrlInheritAppendPath( Site target, Site source, boolean sourceDominant,
                                                            Map<Object, Object> context )
    {
        String src = source.getChildSiteUrlInheritAppendPath();
        if ( src != null )
        {
            if ( sourceDominant || target.getChildSiteUrlInheritAppendPath() == null )
            {
                target.setChildSiteUrlInheritAppendPath( src );
                target.setLocation( "child.site.url.inherit.append.path",
                                    source.getLocation( "child.site.url.inherit.append.path" ) );
            }
        }
    }

    protected void mergeSite_Id( Site target, Site source, boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getId();
        if ( src != null )
        {
            if ( sourceDominant || target.getId() == null )
            {
                target.setId( src );
                target.setLocation( "id", source.getLocation( "id" ) );
            }
        }
    }

    protected void mergeSite_Name( Site target, Site source, boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getName();
        if ( src != null )
        {
            if ( sourceDominant || target.getName() == null )
            {
                target.setName( src );
                target.setLocation( "name", source.getLocation( "name" ) );
            }
        }
    }

    protected void mergeSite_Url( Site target, Site source, boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getUrl() == null )
            {
                target.setUrl( src );
                target.setLocation( "url", source.getLocation( "url" ) );
            }
        }
    }

    protected void mergeRepository( Repository target, Repository source, boolean sourceDominant,
                                    Map<Object, Object> context )
    {
        mergeRepositoryBase( target, source, sourceDominant, context );
        mergeRepository_Releases( target, source, sourceDominant, context );
        mergeRepository_Snapshots( target, source, sourceDominant, context );
    }

    protected void mergeRepository_Releases( Repository target, Repository source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        RepositoryPolicy src = source.getReleases();
        if ( src != null )
        {
            RepositoryPolicy tgt = target.getReleases();
            if ( tgt == null )
            {
                tgt = new RepositoryPolicy();
                target.setReleases( tgt );
            }
            mergeRepositoryPolicy( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeRepository_Snapshots( Repository target, Repository source, boolean sourceDominant,
                                              Map<Object, Object> context )
    {
        RepositoryPolicy src = source.getSnapshots();
        if ( src != null )
        {
            RepositoryPolicy tgt = target.getSnapshots();
            if ( tgt == null )
            {
                tgt = new RepositoryPolicy();
                target.setSnapshots( tgt );
            }
            mergeRepositoryPolicy( tgt, src, sourceDominant, context );
        }
    }

    protected void mergeRepositoryBase( RepositoryBase target, RepositoryBase source, boolean sourceDominant,
                                        Map<Object, Object> context )
    {
        mergeRepositoryBase_Id( target, source, sourceDominant, context );
        mergeRepositoryBase_Name( target, source, sourceDominant, context );
        mergeRepositoryBase_Url( target, source, sourceDominant, context );
        mergeRepositoryBase_Layout( target, source, sourceDominant, context );
    }

    protected void mergeRepositoryBase_Id( RepositoryBase target, RepositoryBase source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getId();
        if ( src != null )
        {
            if ( sourceDominant || target.getId() == null )
            {
                target.setId( src );
                target.setLocation( "id", source.getLocation( "id" ) );
            }
        }
    }

    protected void mergeRepositoryBase_Url( RepositoryBase target, RepositoryBase source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        String src = source.getUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getUrl() == null )
            {
                target.setUrl( src );
                target.setLocation( "url", source.getLocation( "url" ) );
            }
        }
    }

    protected void mergeRepositoryBase_Name( RepositoryBase target, RepositoryBase source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getName();
        if ( src != null )
        {
            if ( sourceDominant || target.getName() == null )
            {
                target.setName( src );
                target.setLocation( "name", source.getLocation( "name" ) );
            }
        }
    }

    protected void mergeRepositoryBase_Layout( RepositoryBase target, RepositoryBase source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        String src = source.getLayout();
        if ( src != null )
        {
            if ( sourceDominant || target.getLayout() == null )
            {
                target.setLayout( src );
                target.setLocation( "layout", source.getLocation( "layout" ) );
            }
        }
    }

    protected void mergeRepositoryPolicy( RepositoryPolicy target, RepositoryPolicy source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        mergeRepositoryPolicy_Enabled( target, source, sourceDominant, context );
        mergeRepositoryPolicy_UpdatePolicy( target, source, sourceDominant, context );
        mergeRepositoryPolicy_ChecksumPolicy( target, source, sourceDominant, context );
    }

    protected void mergeRepositoryPolicy_Enabled( RepositoryPolicy target, RepositoryPolicy source,
                                                  boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getEnabled();
        if ( src != null )
        {
            if ( sourceDominant || target.getEnabled() == null )
            {
                target.setEnabled( src );
                target.setLocation( "enabled", source.getLocation( "enabled" ) );
            }
        }
    }

    protected void mergeRepositoryPolicy_UpdatePolicy( RepositoryPolicy target, RepositoryPolicy source,
                                                       boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getUpdatePolicy();
        if ( src != null )
        {
            if ( sourceDominant || target.getUpdatePolicy() == null )
            {
                target.setUpdatePolicy( src );
                target.setLocation( "updatePolicy", source.getLocation( "updatePolicy" ) );
            }
        }
    }

    protected void mergeRepositoryPolicy_ChecksumPolicy( RepositoryPolicy target, RepositoryPolicy source,
                                                         boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getChecksumPolicy();
        if ( src != null )
        {
            if ( sourceDominant || target.getChecksumPolicy() == null )
            {
                target.setChecksumPolicy( src );
                target.setLocation( "checksumPolicy", source.getLocation( "checksumPolicy" ) );
            }
        }
    }

    protected void mergeDependency( Dependency target, Dependency source, boolean sourceDominant,
                                    Map<Object, Object> context )
    {
        mergeDependency_GroupId( target, source, sourceDominant, context );
        mergeDependency_ArtifactId( target, source, sourceDominant, context );
        mergeDependency_Version( target, source, sourceDominant, context );
        mergeDependency_Type( target, source, sourceDominant, context );
        mergeDependency_Classifier( target, source, sourceDominant, context );
        mergeDependency_Scope( target, source, sourceDominant, context );
        mergeDependency_SystemPath( target, source, sourceDominant, context );
        mergeDependency_Optional( target, source, sourceDominant, context );
        mergeDependency_Exclusions( target, source, sourceDominant, context );
    }

    protected void mergeDependency_GroupId( Dependency target, Dependency source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        String src = source.getGroupId();
        if ( src != null )
        {
            if ( sourceDominant || target.getGroupId() == null )
            {
                target.setGroupId( src );
                target.setLocation( "groupId", source.getLocation( "groupId" ) );
            }
        }
    }

    protected void mergeDependency_ArtifactId( Dependency target, Dependency source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        String src = source.getArtifactId();
        if ( src != null )
        {
            if ( sourceDominant || target.getArtifactId() == null )
            {
                target.setArtifactId( src );
                target.setLocation( "artifactId", source.getLocation( "artifactId" ) );
            }
        }
    }

    protected void mergeDependency_Version( Dependency target, Dependency source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        String src = source.getVersion();
        if ( src != null )
        {
            if ( sourceDominant || target.getVersion() == null )
            {
                target.setVersion( src );
                target.setLocation( "version", source.getLocation( "version" ) );
            }
        }
    }

    protected void mergeDependency_Type( Dependency target, Dependency source, boolean sourceDominant,
                                         Map<Object, Object> context )
    {
        String src = source.getType();
        if ( src != null )
        {
            if ( sourceDominant || target.getType() == null )
            {
                target.setType( src );
                target.setLocation( "type", source.getLocation( "type" ) );
            }
        }
    }

    protected void mergeDependency_Classifier( Dependency target, Dependency source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        String src = source.getClassifier();
        if ( src != null )
        {
            if ( sourceDominant || target.getClassifier() == null )
            {
                target.setClassifier( src );
                target.setLocation( "classifier", source.getLocation( "classifier" ) );
            }
        }
    }

    protected void mergeDependency_Scope( Dependency target, Dependency source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        String src = source.getScope();
        if ( src != null )
        {
            if ( sourceDominant || target.getScope() == null )
            {
                target.setScope( src );
                target.setLocation( "scope", source.getLocation( "scope" ) );
            }
        }
    }

    protected void mergeDependency_SystemPath( Dependency target, Dependency source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        String src = source.getSystemPath();
        if ( src != null )
        {
            if ( sourceDominant || target.getSystemPath() == null )
            {
                target.setSystemPath( src );
                target.setLocation( "systemPath", source.getLocation( "systemPath" ) );
            }
        }
    }

    protected void mergeDependency_Optional( Dependency target, Dependency source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getOptional();
        if ( src != null )
        {
            if ( sourceDominant || target.getOptional() == null )
            {
                target.setOptional( src );
                target.setLocation( "optional", source.getLocation( "optional" ) );
            }
        }
    }

    protected void mergeDependency_Exclusions( Dependency target, Dependency source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        target.setExclusions( merge( target.getExclusions(), source.getExclusions(),
                sourceDominant, new ExclusionKeyComputer() ) );
    }

    protected void mergeExclusion( Exclusion target, Exclusion source, boolean sourceDominant,
                                   Map<Object, Object> context )
    {
        mergeExclusion_GroupId( target, source, sourceDominant, context );
        mergeExclusion_ArtifactId( target, source, sourceDominant, context );
    }

    protected void mergeExclusion_GroupId( Exclusion target, Exclusion source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getGroupId();
        if ( src != null )
        {
            if ( sourceDominant || target.getGroupId() == null )
            {
                target.setGroupId( src );
                target.setLocation( "groupId", source.getLocation( "groupId" ) );
            }
        }
    }

    protected void mergeExclusion_ArtifactId( Exclusion target, Exclusion source, boolean sourceDominant,
                                              Map<Object, Object> context )
    {
        String src = source.getArtifactId();
        if ( src != null )
        {
            if ( sourceDominant || target.getArtifactId() == null )
            {
                target.setArtifactId( src );
                target.setLocation( "artifactId", source.getLocation( "artifactId" ) );
            }
        }
    }

    protected void mergeReporting( Reporting target, Reporting source, boolean sourceDominant,
                                   Map<Object, Object> context )
    {
        mergeReporting_OutputDirectory( target, source, sourceDominant, context );
        mergeReporting_ExcludeDefaults( target, source, sourceDominant, context );
        mergeReporting_Plugins( target, source, sourceDominant, context );
    }

    protected void mergeReporting_OutputDirectory( Reporting target, Reporting source, boolean sourceDominant,
                                                   Map<Object, Object> context )
    {
        String src = source.getOutputDirectory();
        if ( src != null )
        {
            if ( sourceDominant || target.getOutputDirectory() == null )
            {
                target.setOutputDirectory( src );
                target.setLocation( "outputDirectory", source.getLocation( "outputDirectory" ) );
            }
        }
    }

    protected void mergeReporting_ExcludeDefaults( Reporting target, Reporting source, boolean sourceDominant,
                                                   Map<Object, Object> context )
    {
        String src = source.getExcludeDefaults();
        if ( src != null )
        {
            if ( sourceDominant || target.getExcludeDefaults() == null )
            {
                target.setExcludeDefaults( src );
                target.setLocation( "excludeDefaults", source.getLocation( "excludeDefaults" ) );
            }
        }
    }

    protected void mergeReporting_Plugins( Reporting target, Reporting source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        target.setPlugins( merge( target.getPlugins(), source.getPlugins(),
                sourceDominant, new ReportPluginKeyComputer() ) );
    }

    protected void mergeReportPlugin( ReportPlugin target, ReportPlugin source, boolean sourceDominant,
                                      Map<Object, Object> context )
    {
        mergeConfigurationContainer( target, source, sourceDominant, context );
        mergeReportPlugin_GroupId( target, source, sourceDominant, context );
        mergeReportPlugin_ArtifactId( target, source, sourceDominant, context );
        mergeReportPlugin_Version( target, source, sourceDominant, context );
        mergeReportPlugin_ReportSets( target, source, sourceDominant, context );
    }

    protected void mergeReportPlugin_GroupId( ReportPlugin target, ReportPlugin source, boolean sourceDominant,
                                              Map<Object, Object> context )
    {
        String src = source.getGroupId();
        if ( src != null )
        {
            if ( sourceDominant || target.getGroupId() == null )
            {
                target.setGroupId( src );
                target.setLocation( "groupId", source.getLocation( "groupId" ) );
            }
        }
    }

    protected void mergeReportPlugin_ArtifactId( ReportPlugin target, ReportPlugin source, boolean sourceDominant,
                                                 Map<Object, Object> context )
    {
        String src = source.getArtifactId();
        if ( src != null )
        {
            if ( sourceDominant || target.getArtifactId() == null )
            {
                target.setArtifactId( src );
                target.setLocation( "artifactId", source.getLocation( "artifactId" ) );
            }
        }
    }

    protected void mergeReportPlugin_Version( ReportPlugin target, ReportPlugin source, boolean sourceDominant,
                                              Map<Object, Object> context )
    {
        String src = source.getVersion();
        if ( src != null )
        {
            if ( sourceDominant || target.getVersion() == null )
            {
                target.setVersion( src );
                target.setLocation( "version", source.getLocation( "version" ) );
            }
        }
    }

    protected void mergeReportPlugin_ReportSets( ReportPlugin target, ReportPlugin source, boolean sourceDominant,
                                                 Map<Object, Object> context )
    {
        target.setReportSets( merge( target.getReportSets(), source.getReportSets(),
                sourceDominant, new ReportSetKeyComputer() ) );
    }

    protected void mergeReportSet( ReportSet target, ReportSet source, boolean sourceDominant,
                                   Map<Object, Object> context )
    {
        mergeConfigurationContainer( target, source, sourceDominant, context );
        mergeReportSet_Id( target, source, sourceDominant, context );
        mergeReportSet_Reports( target, source, sourceDominant, context );
    }

    protected void mergeReportSet_Id( ReportSet target, ReportSet source, boolean sourceDominant,
                                      Map<Object, Object> context )
    {
        String src = source.getId();
        if ( src != null )
        {
            if ( sourceDominant || target.getId() == null )
            {
                target.setId( src );
                target.setLocation( "id", source.getLocation( "id" ) );
            }
        }
    }

    protected void mergeReportSet_Reports( ReportSet target, ReportSet source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        List<String> src = source.getReports();
        if ( !src.isEmpty() )
        {
            List<String> tgt = target.getReports();
            List<String> merged = new ArrayList<>( tgt.size() + src.size() );
            merged.addAll( tgt );
            merged.addAll( src );
            target.setReports( merged );

            InputLocation sourceLocation = source.getLocation( "reports" );
            if ( sourceLocation != null )
            {
                InputLocation targetLocation = target.getLocation( "reports" );
                if ( targetLocation == null )
                {
                    target.setLocation( "reports", sourceLocation );
                }
                else
                {
                    for ( int i = 0; i < src.size(); i++ )
                    {
                        targetLocation.setLocation( Integer.valueOf( tgt.size() + i ),
                                                    sourceLocation.getLocation( Integer.valueOf( i ) ) );
                    }
                }
            }
        }
    }

    protected void mergeDependencyManagement( DependencyManagement target, DependencyManagement source,
                                              boolean sourceDominant, Map<Object, Object> context )
    {
        mergeDependencyManagement_Dependencies( target, source, sourceDominant, context );
    }

    protected void mergeDependencyManagement_Dependencies( DependencyManagement target, DependencyManagement source,
                                                           boolean sourceDominant, Map<Object, Object> context )
    {
        target.setDependencies( merge( target.getDependencies(), source.getDependencies(),
                                       sourceDominant, new DependencyKeyComputer() ) );
    }

    protected void mergeParent( Parent target, Parent source, boolean sourceDominant, Map<Object, Object> context )
    {
        mergeParent_GroupId( target, source, sourceDominant, context );
        mergeParent_ArtifactId( target, source, sourceDominant, context );
        mergeParent_Version( target, source, sourceDominant, context );
        mergeParent_RelativePath( target, source, sourceDominant, context );
    }

    protected void mergeParent_GroupId( Parent target, Parent source, boolean sourceDominant,
                                        Map<Object, Object> context )
    {
        String src = source.getGroupId();
        if ( src != null )
        {
            if ( sourceDominant || target.getGroupId() == null )
            {
                target.setGroupId( src );
                target.setLocation( "groupId", source.getLocation( "groupId" ) );
            }
        }
    }

    protected void mergeParent_ArtifactId( Parent target, Parent source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getArtifactId();
        if ( src != null )
        {
            if ( sourceDominant || target.getArtifactId() == null )
            {
                target.setArtifactId( src );
                target.setLocation( "artifactId", source.getLocation( "artifactId" ) );
            }
        }
    }

    protected void mergeParent_Version( Parent target, Parent source, boolean sourceDominant,
                                        Map<Object, Object> context )
    {
        String src = source.getVersion();
        if ( src != null )
        {
            if ( sourceDominant || target.getVersion() == null )
            {
                target.setVersion( src );
                target.setLocation( "version", source.getLocation( "version" ) );
            }
        }
    }

    protected void mergeParent_RelativePath( Parent target, Parent source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getRelativePath();
        if ( src != null )
        {
            if ( sourceDominant || target.getRelativePath() == null )
            {
                target.setRelativePath( src );
                target.setLocation( "relativePath", source.getLocation( "relativePath" ) );
            }
        }
    }

    protected void mergeOrganization( Organization target, Organization source, boolean sourceDominant,
                                      Map<Object, Object> context )
    {
        mergeOrganization_Name( target, source, sourceDominant, context );
        mergeOrganization_Url( target, source, sourceDominant, context );
    }

    protected void mergeOrganization_Name( Organization target, Organization source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getName();
        if ( src != null )
        {
            if ( sourceDominant || target.getName() == null )
            {
                target.setName( src );
                target.setLocation( "name", source.getLocation( "name" ) );
            }
        }
    }

    protected void mergeOrganization_Url( Organization target, Organization source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        String src = source.getUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getUrl() == null )
            {
                target.setUrl( src );
                target.setLocation( "url", source.getLocation( "url" ) );
            }
        }
    }

    protected void mergeLicense( License target, License source, boolean sourceDominant, Map<Object, Object> context )
    {
        mergeLicense_Name( target, source, sourceDominant, context );
        mergeLicense_Url( target, source, sourceDominant, context );
        mergeLicense_Distribution( target, source, sourceDominant, context );
        mergeLicense_Comments( target, source, sourceDominant, context );
    }

    protected void mergeLicense_Name( License target, License source, boolean sourceDominant,
                                      Map<Object, Object> context )
    {
        String src = source.getName();
        if ( src != null )
        {
            if ( sourceDominant || target.getName() == null )
            {
                target.setName( src );
                target.setLocation( "name", source.getLocation( "name" ) );
            }
        }
    }

    protected void mergeLicense_Url( License target, License source, boolean sourceDominant,
                                     Map<Object, Object> context )
    {
        String src = source.getUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getUrl() == null )
            {
                target.setUrl( src );
                target.setLocation( "url", source.getLocation( "url" ) );
            }
        }
    }

    protected void mergeLicense_Distribution( License target, License source, boolean sourceDominant,
                                              Map<Object, Object> context )
    {
        String src = source.getDistribution();
        if ( src != null )
        {
            if ( sourceDominant || target.getDistribution() == null )
            {
                target.setDistribution( src );
                target.setLocation( "distribution", source.getLocation( "distribution" ) );
            }
        }
    }

    protected void mergeLicense_Comments( License target, License source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        String src = source.getComments();
        if ( src != null )
        {
            if ( sourceDominant || target.getComments() == null )
            {
                target.setComments( src );
                target.setLocation( "comments", source.getLocation( "comments" ) );
            }
        }
    }

    protected void mergeMailingList( MailingList target, MailingList source, boolean sourceDominant,
                                     Map<Object, Object> context )
    {
        mergeMailingList_Name( target, source, sourceDominant, context );
        mergeMailingList_Subscribe( target, source, sourceDominant, context );
        mergeMailingList_Unsubscribe( target, source, sourceDominant, context );
        mergeMailingList_Post( target, source, sourceDominant, context );
        mergeMailingList_OtherArchives( target, source, sourceDominant, context );
    }

    protected void mergeMailingList_Name( MailingList target, MailingList source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        String src = source.getName();
        if ( src != null )
        {
            if ( sourceDominant || target.getName() == null )
            {
                target.setName( src );
                target.setLocation( "name", source.getLocation( "name" ) );
            }
        }
    }

    protected void mergeMailingList_Subscribe( MailingList target, MailingList source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        String src = source.getSubscribe();
        if ( src != null )
        {
            if ( sourceDominant || target.getSubscribe() == null )
            {
                target.setSubscribe( src );
                target.setLocation( "subscribe", source.getLocation( "subscribe" ) );
            }
        }
    }

    protected void mergeMailingList_Unsubscribe( MailingList target, MailingList source, boolean sourceDominant,
                                                 Map<Object, Object> context )
    {
        String src = source.getUnsubscribe();
        if ( src != null )
        {
            if ( sourceDominant || target.getUnsubscribe() == null )
            {
                target.setUnsubscribe( src );
                target.setLocation( "unsubscribe", source.getLocation( "unsubscribe" ) );
            }
        }
    }

    protected void mergeMailingList_Post( MailingList target, MailingList source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        String src = source.getPost();
        if ( src != null )
        {
            if ( sourceDominant || target.getPost() == null )
            {
                target.setPost( src );
                target.setLocation( "post", source.getLocation( "post" ) );
            }
        }
    }

    protected void mergeMailingList_Archive( MailingList target, MailingList source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getArchive();
        if ( src != null )
        {
            if ( sourceDominant || target.getArchive() == null )
            {
                target.setArchive( src );
                target.setLocation( "archive", source.getLocation( "archive" ) );
            }
        }
    }

    protected void mergeMailingList_OtherArchives( MailingList target, MailingList source, boolean sourceDominant,
                                                   Map<Object, Object> context )
    {
        List<String> src = source.getOtherArchives();
        if ( !src.isEmpty() )
        {
            List<String> tgt = target.getOtherArchives();
            List<String> merged = new ArrayList<>( tgt.size() + src.size() );
            merged.addAll( tgt );
            merged.addAll( src );
            target.setOtherArchives( merged );
        }
    }

    protected void mergeDeveloper( Developer target, Developer source, boolean sourceDominant,
                                   Map<Object, Object> context )
    {
        mergeContributor( target, source, sourceDominant, context );
        mergeDeveloper_Id( target, source, sourceDominant, context );
    }

    protected void mergeDeveloper_Id( Developer target, Developer source, boolean sourceDominant,
                                      Map<Object, Object> context )
    {
        String src = source.getId();
        if ( src != null )
        {
            if ( sourceDominant || target.getId() == null )
            {
                target.setId( src );
                target.setLocation( "id", source.getLocation( "id" ) );
            }
        }
    }

    protected void mergeContributor( Contributor target, Contributor source, boolean sourceDominant,
                                     Map<Object, Object> context )
    {
        mergeContributor_Name( target, source, sourceDominant, context );
        mergeContributor_Email( target, source, sourceDominant, context );
        mergeContributor_Url( target, source, sourceDominant, context );
        mergeContributor_Organization( target, source, sourceDominant, context );
        mergeContributor_OrganizationUrl( target, source, sourceDominant, context );
        mergeContributor_Timezone( target, source, sourceDominant, context );
        mergeContributor_Roles( target, source, sourceDominant, context );
        mergeContributor_Properties( target, source, sourceDominant, context );
    }

    protected void mergeContributor_Name( Contributor target, Contributor source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        String src = source.getName();
        if ( src != null )
        {
            if ( sourceDominant || target.getName() == null )
            {
                target.setName( src );
                target.setLocation( "name", source.getLocation( "name" ) );
            }
        }
    }

    protected void mergeContributor_Email( Contributor target, Contributor source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getEmail();
        if ( src != null )
        {
            if ( sourceDominant || target.getEmail() == null )
            {
                target.setEmail( src );
                target.setLocation( "email", source.getLocation( "email" ) );
            }
        }
    }

    protected void mergeContributor_Url( Contributor target, Contributor source, boolean sourceDominant,
                                         Map<Object, Object> context )
    {
        String src = source.getUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getUrl() == null )
            {
                target.setUrl( src );
                target.setLocation( "url", source.getLocation( "url" ) );
            }
        }
    }

    protected void mergeContributor_Organization( Contributor target, Contributor source, boolean sourceDominant,
                                                  Map<Object, Object> context )
    {
        String src = source.getOrganization();
        if ( src != null )
        {
            if ( sourceDominant || target.getOrganization() == null )
            {
                target.setOrganization( src );
                target.setLocation( "organization", source.getLocation( "organization" ) );
            }
        }
    }

    protected void mergeContributor_OrganizationUrl( Contributor target, Contributor source, boolean sourceDominant,
                                                     Map<Object, Object> context )
    {
        String src = source.getOrganizationUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getOrganizationUrl() == null )
            {
                target.setOrganizationUrl( src );
                target.setLocation( "organizationUrl", source.getLocation( "organizationUrl" ) );
            }
        }
    }

    protected void mergeContributor_Timezone( Contributor target, Contributor source, boolean sourceDominant,
                                              Map<Object, Object> context )
    {
        String src = source.getTimezone();
        if ( src != null )
        {
            if ( sourceDominant || target.getTimezone() == null )
            {
                target.setTimezone( src );
                target.setLocation( "timezone", source.getLocation( "timezone" ) );
            }
        }
    }

    protected void mergeContributor_Roles( Contributor target, Contributor source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        List<String> src = source.getRoles();
        if ( !src.isEmpty() )
        {
            List<String> tgt = target.getRoles();
            List<String> merged = new ArrayList<>( tgt.size() + src.size() );
            merged.addAll( tgt );
            merged.addAll( src );
            target.setRoles( merged );
        }
    }

    protected void mergeContributor_Properties( Contributor target, Contributor source, boolean sourceDominant,
                                                Map<Object, Object> context )
    {
        Properties merged = new Properties();
        if ( sourceDominant )
        {
            merged.putAll( target.getProperties() );
            merged.putAll( source.getProperties() );
        }
        else
        {
            merged.putAll( source.getProperties() );
            merged.putAll( target.getProperties() );
        }
        target.setProperties( merged );
        target.setLocation( "properties", InputLocation.merge( target.getLocation( "properties" ),
                                                               source.getLocation( "properties" ), sourceDominant ) );
    }

    protected void mergeIssueManagement( IssueManagement target, IssueManagement source, boolean sourceDominant,
                                         Map<Object, Object> context )
    {
        mergeIssueManagement_Url( target, source, sourceDominant, context );
        mergeIssueManagement_System( target, source, sourceDominant, context );
    }

    protected void mergeIssueManagement_System( IssueManagement target, IssueManagement source, boolean sourceDominant,
                                                Map<Object, Object> context )
    {
        String src = source.getSystem();
        if ( src != null )
        {
            if ( sourceDominant || target.getSystem() == null )
            {
                target.setSystem( src );
                target.setLocation( "system", source.getLocation( "system" ) );
            }
        }
    }

    protected void mergeIssueManagement_Url( IssueManagement target, IssueManagement source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getUrl() == null )
            {
                target.setUrl( src );
                target.setLocation( "url", source.getLocation( "url" ) );
            }
        }
    }

    protected void mergeScm( Scm target, Scm source, boolean sourceDominant, Map<Object, Object> context )
    {
        mergeScm_ChildScmConnectionInheritAppendPath( target, source, sourceDominant, context );
        mergeScm_ChildScmDeveloperConnectionInheritAppendPath( target, source, sourceDominant, context );
        mergeScm_ChildScmUrlInheritAppendPath( target, source, sourceDominant, context );
        mergeScm_Url( target, source, sourceDominant, context );
        mergeScm_Connection( target, source, sourceDominant, context );
        mergeScm_DeveloperConnection( target, source, sourceDominant, context );
        mergeScm_Tag( target, source, sourceDominant, context );
    }

    protected void mergeScm_ChildScmConnectionInheritAppendPath( Scm target, Scm source, boolean sourceDominant,
                                                                 Map<Object, Object> context )
    {
        String src = source.getChildScmConnectionInheritAppendPath();
        if ( src != null )
        {
            if ( sourceDominant || target.getChildScmConnectionInheritAppendPath() == null )
            {
                target.setChildScmConnectionInheritAppendPath( src );
                target.setLocation( "child.scm.connection.inherit.append.path",
                                    source.getLocation( "child.scm.connection.inherit.append.path" ) );
            }
        }
    }

    protected void mergeScm_ChildScmDeveloperConnectionInheritAppendPath( Scm target, Scm source,
                                                                          boolean sourceDominant,
                                                                          Map<Object, Object> context )
    {
        String src = source.getChildScmDeveloperConnectionInheritAppendPath();
        if ( src != null )
        {
            if ( sourceDominant || target.getChildScmDeveloperConnectionInheritAppendPath() == null )
            {
                target.setChildScmDeveloperConnectionInheritAppendPath( src );
                target.setLocation( "child.scm.developerConnection.inherit.append.path",
                                    source.getLocation( "child.scm.developerConnection.inherit.append.path" ) );
            }
        }
    }

    protected void mergeScm_ChildScmUrlInheritAppendPath( Scm target, Scm source, boolean sourceDominant,
                                                          Map<Object, Object> context )
    {
        String src = source.getChildScmUrlInheritAppendPath();
        if ( src != null )
        {
            if ( sourceDominant || target.getChildScmUrlInheritAppendPath() == null )
            {
                target.setChildScmUrlInheritAppendPath( src );
                target.setLocation( "child.scm.url.inherit.append.path",
                                    source.getLocation( "child.scm.url.inherit.append.path" ) );
            }
        }
    }

    protected void mergeScm_Url( Scm target, Scm source, boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getUrl() == null )
            {
                target.setUrl( src );
                target.setLocation( "url", source.getLocation( "url" ) );
            }
        }
    }

    protected void mergeScm_Connection( Scm target, Scm source, boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getConnection();
        if ( src != null )
        {
            if ( sourceDominant || target.getConnection() == null )
            {
                target.setConnection( src );
                target.setLocation( "connection", source.getLocation( "connection" ) );
            }
        }
    }

    protected void mergeScm_DeveloperConnection( Scm target, Scm source, boolean sourceDominant,
                                                 Map<Object, Object> context )
    {
        String src = source.getDeveloperConnection();
        if ( src != null )
        {
            if ( sourceDominant || target.getDeveloperConnection() == null )
            {
                target.setDeveloperConnection( src );
                target.setLocation( "developerConnection", source.getLocation( "developerConnection" ) );
            }
        }
    }

    protected void mergeScm_Tag( Scm target, Scm source, boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getTag();
        if ( src != null )
        {
            if ( sourceDominant || target.getTag() == null )
            {
                target.setTag( src );
                target.setLocation( "tag", source.getLocation( "tag" ) );
            }
        }
    }

    protected void mergeCiManagement( CiManagement target, CiManagement source, boolean sourceDominant,
                                      Map<Object, Object> context )
    {
        mergeCiManagement_System( target, source, sourceDominant, context );
        mergeCiManagement_Url( target, source, sourceDominant, context );
        mergeCiManagement_Notifiers( target, source, sourceDominant, context );
    }

    protected void mergeCiManagement_System( CiManagement target, CiManagement source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getSystem();
        if ( src != null )
        {
            if ( sourceDominant || target.getSystem() == null )
            {
                target.setSystem( src );
                target.setLocation( "system", source.getLocation( "system" ) );
            }
        }
    }

    protected void mergeCiManagement_Url( CiManagement target, CiManagement source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        String src = source.getUrl();
        if ( src != null )
        {
            if ( sourceDominant || target.getUrl() == null )
            {
                target.setUrl( src );
                target.setLocation( "url", source.getLocation( "url" ) );
            }
        }
    }

    protected void mergeCiManagement_Notifiers( CiManagement target, CiManagement source, boolean sourceDominant,
                                                Map<Object, Object> context )
    {
        target.setNotifiers( merge( target.getNotifiers(), source.getNotifiers(),
                                    sourceDominant, new NotifierKeyComputer() ) );
    }

    protected void mergeNotifier( Notifier target, Notifier source, boolean sourceDominant,
                                  Map<Object, Object> context )
    {
        mergeNotifier_Type( target, source, sourceDominant, context );
        mergeNotifier_Address( target, source, sourceDominant, context );
        mergeNotifier_Configuration( target, source, sourceDominant, context );
        mergeNotifier_SendOnError( target, source, sourceDominant, context );
        mergeNotifier_SendOnFailure( target, source, sourceDominant, context );
        mergeNotifier_SendOnSuccess( target, source, sourceDominant, context );
        mergeNotifier_SendOnWarning( target, source, sourceDominant, context );
    }

    protected void mergeNotifier_Type( Notifier target, Notifier source, boolean sourceDominant,
                                       Map<Object, Object> context )
    {
        String src = source.getType();
        if ( src != null )
        {
            if ( sourceDominant || target.getType() == null )
            {
                target.setType( src );
            }
        }
    }

    protected void mergeNotifier_Address( Notifier target, Notifier source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        String src = source.getAddress();
        if ( src != null )
        {
            if ( sourceDominant || target.getAddress() == null )
            {
                target.setAddress( src );
            }
        }
    }

    protected void mergeNotifier_Configuration( Notifier target, Notifier source, boolean sourceDominant,
                                                Map<Object, Object> context )
    {
        Properties merged = new Properties();
        if ( sourceDominant )
        {
            merged.putAll( target.getConfiguration() );
            merged.putAll( source.getConfiguration() );
        }
        else
        {
            merged.putAll( source.getConfiguration() );
            merged.putAll( target.getConfiguration() );
        }
        target.setConfiguration( merged );
    }

    protected void mergeNotifier_SendOnError( Notifier target, Notifier source, boolean sourceDominant,
                                              Map<Object, Object> context )
    {
        if ( sourceDominant )
        {
            target.setSendOnError( source.isSendOnError() );
        }
    }

    protected void mergeNotifier_SendOnFailure( Notifier target, Notifier source, boolean sourceDominant,
                                                Map<Object, Object> context )
    {
        if ( sourceDominant )
        {
            target.setSendOnFailure( source.isSendOnFailure() );
        }
    }

    protected void mergeNotifier_SendOnSuccess( Notifier target, Notifier source, boolean sourceDominant,
                                                Map<Object, Object> context )
    {
        if ( sourceDominant )
        {
            target.setSendOnSuccess( source.isSendOnSuccess() );
        }
    }

    protected void mergeNotifier_SendOnWarning( Notifier target, Notifier source, boolean sourceDominant,
                                                Map<Object, Object> context )
    {
        if ( sourceDominant )
        {
            target.setSendOnWarning( source.isSendOnWarning() );
        }
    }

    protected void mergePrerequisites( Prerequisites target, Prerequisites source, boolean sourceDominant,
                                       Map<Object, Object> context )
    {
        mergePrerequisites_Maven( target, source, sourceDominant, context );
    }

    protected void mergePrerequisites_Maven( Prerequisites target, Prerequisites source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getMaven();
        if ( src != null )
        {
            if ( sourceDominant || target.getMaven() == null )
            {
                target.setMaven( src );
                target.setLocation( "maven", source.getLocation( "maven" ) );
            }
        }
    }

    protected void mergeBuild( Build target, Build source, boolean sourceDominant, Map<Object, Object> context )
    {
        mergeBuildBase( target, source, sourceDominant, context );
        mergeBuild_SourceDirectory( target, source, sourceDominant, context );
        mergeBuild_ScriptSourceDirectory( target, source, sourceDominant, context );
        mergeBuild_TestSourceDirectory( target, source, sourceDominant, context );
        mergeBuild_OutputDirectory( target, source, sourceDominant, context );
        mergeBuild_TestOutputDirectory( target, source, sourceDominant, context );
        mergeBuild_Extensions( target, source, sourceDominant, context );
    }

    protected void mergeBuild_SourceDirectory( Build target, Build source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        String src = source.getSourceDirectory();
        if ( src != null )
        {
            if ( sourceDominant || target.getSourceDirectory() == null )
            {
                target.setSourceDirectory( src );
                target.setLocation( "sourceDirectory", source.getLocation( "sourceDirectory" ) );
            }
        }
    }

    protected void mergeBuild_ScriptSourceDirectory( Build target, Build source, boolean sourceDominant,
                                                     Map<Object, Object> context )
    {
        String src = source.getScriptSourceDirectory();
        if ( src != null )
        {
            if ( sourceDominant || target.getScriptSourceDirectory() == null )
            {
                target.setScriptSourceDirectory( src );
                target.setLocation( "scriptSourceDirectory", source.getLocation( "scriptSourceDirectory" ) );
            }
        }
    }

    protected void mergeBuild_TestSourceDirectory( Build target, Build source, boolean sourceDominant,
                                                   Map<Object, Object> context )
    {
        String src = source.getTestSourceDirectory();
        if ( src != null )
        {
            if ( sourceDominant || target.getTestSourceDirectory() == null )
            {
                target.setTestSourceDirectory( src );
                target.setLocation( "testSourceDirectory", source.getLocation( "testSourceDirectory" ) );
            }
        }
    }

    protected void mergeBuild_OutputDirectory( Build target, Build source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        String src = source.getOutputDirectory();
        if ( src != null )
        {
            if ( sourceDominant || target.getOutputDirectory() == null )
            {
                target.setOutputDirectory( src );
                target.setLocation( "outputDirectory", source.getLocation( "outputDirectory" ) );
            }
        }
    }

    protected void mergeBuild_TestOutputDirectory( Build target, Build source, boolean sourceDominant,
                                                   Map<Object, Object> context )
    {
        String src = source.getTestOutputDirectory();
        if ( src != null )
        {
            if ( sourceDominant || target.getTestOutputDirectory() == null )
            {
                target.setTestOutputDirectory( src );
                target.setLocation( "testOutputDirectory", source.getLocation( "testOutputDirectory" ) );
            }
        }
    }

    protected void mergeBuild_Extensions( Build target, Build source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        target.setExtensions( merge( target.getExtensions(), source.getExtensions(),
                                     sourceDominant, new ExtensionKeyComputer() ) );
    }

    protected void mergeExtension( Extension target, Extension source, boolean sourceDominant,
                                   Map<Object, Object> context )
    {
        mergeExtension_GroupId( target, source, sourceDominant, context );
        mergeExtension_ArtifactId( target, source, sourceDominant, context );
        mergeExtension_Version( target, source, sourceDominant, context );
    }

    protected void mergeExtension_GroupId( Extension target, Extension source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getGroupId();
        if ( src != null )
        {
            if ( sourceDominant || target.getGroupId() == null )
            {
                target.setGroupId( src );
                target.setLocation( "groupId", source.getLocation( "groupId" ) );
            }
        }
    }

    protected void mergeExtension_ArtifactId( Extension target, Extension source, boolean sourceDominant,
                                              Map<Object, Object> context )
    {
        String src = source.getArtifactId();
        if ( src != null )
        {
            if ( sourceDominant || target.getArtifactId() == null )
            {
                target.setArtifactId( src );
                target.setLocation( "artifactId", source.getLocation( "artifactId" ) );
            }
        }
    }

    protected void mergeExtension_Version( Extension target, Extension source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getVersion();
        if ( src != null )
        {
            if ( sourceDominant || target.getVersion() == null )
            {
                target.setVersion( src );
                target.setLocation( "version", source.getLocation( "version" ) );
            }
        }
    }

    protected void mergeBuildBase( BuildBase target, BuildBase source, boolean sourceDominant,
                                   Map<Object, Object> context )
    {
        mergePluginConfiguration( target, source, sourceDominant, context );
        mergeBuildBase_DefaultGoal( target, source, sourceDominant, context );
        mergeBuildBase_FinalName( target, source, sourceDominant, context );
        mergeBuildBase_Directory( target, source, sourceDominant, context );
        mergeBuildBase_Resources( target, source, sourceDominant, context );
        mergeBuildBase_TestResources( target, source, sourceDominant, context );
        mergeBuildBase_Filters( target, source, sourceDominant, context );
    }

    protected void mergeBuildBase_DefaultGoal( BuildBase target, BuildBase source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        String src = source.getDefaultGoal();
        if ( src != null )
        {
            if ( sourceDominant || target.getDefaultGoal() == null )
            {
                target.setDefaultGoal( src );
                target.setLocation( "defaultGoal", source.getLocation( "defaultGoal" ) );
            }
        }
    }

    protected void mergeBuildBase_Directory( BuildBase target, BuildBase source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getDirectory();
        if ( src != null )
        {
            if ( sourceDominant || target.getDirectory() == null )
            {
                target.setDirectory( src );
                target.setLocation( "directory", source.getLocation( "directory" ) );
            }
        }
    }

    protected void mergeBuildBase_FinalName( BuildBase target, BuildBase source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getFinalName();
        if ( src != null )
        {
            if ( sourceDominant || target.getFinalName() == null )
            {
                target.setFinalName( src );
                target.setLocation( "finalName", source.getLocation( "finalName" ) );
            }
        }
    }

    protected void mergeBuildBase_Filters( BuildBase target, BuildBase source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        List<String> src = source.getFilters();
        if ( !src.isEmpty() )
        {
            List<String> tgt = target.getFilters();
            List<String> merged = new ArrayList<>( tgt.size() + src.size() );
            merged.addAll( tgt );
            merged.addAll( src );
            target.setFilters( merged );
        }
    }

    protected void mergeBuildBase_Resources( BuildBase target, BuildBase source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        target.setResources( merge( target.getResources(), source.getResources(),
                                    sourceDominant, new ResourceKeyComputer() ) );
    }

    protected void mergeBuildBase_TestResources( BuildBase target, BuildBase source, boolean sourceDominant,
                                                 Map<Object, Object> context )
    {
        target.setTestResources( merge( target.getTestResources(), source.getTestResources(),
                                        sourceDominant, new ResourceKeyComputer() ) );
    }

    protected void mergePluginConfiguration( PluginConfiguration target, PluginConfiguration source,
                                             boolean sourceDominant, Map<Object, Object> context )
    {
        mergePluginContainer( target, source, sourceDominant, context );
        mergePluginConfiguration_PluginManagement( target, source, sourceDominant, context );
    }

    protected void mergePluginConfiguration_PluginManagement( PluginConfiguration target, PluginConfiguration source,
                                                              boolean sourceDominant, Map<Object, Object> context )
    {
        PluginManagement src = source.getPluginManagement();
        if ( src != null )
        {
            PluginManagement tgt = target.getPluginManagement();
            if ( tgt == null )
            {
                tgt = new PluginManagement();
                target.setPluginManagement( tgt );
            }
            mergePluginManagement( tgt, src, sourceDominant, context );
        }
    }

    protected void mergePluginContainer( PluginContainer target, PluginContainer source,
                                         boolean sourceDominant, Map<Object, Object> context )
    {
        mergePluginContainer_Plugins( target, source, sourceDominant, context );
    }

    protected void mergePluginContainer_Plugins( PluginContainer target, PluginContainer source,
                                                 boolean sourceDominant, Map<Object, Object> context )
    {
        target.setPlugins( merge( target.getPlugins(), source.getPlugins(),
                                  sourceDominant, new PluginKeyComputer() ) );
    }

    protected void mergePluginManagement( PluginManagement target, PluginManagement source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        mergePluginContainer( target, source, sourceDominant, context );
    }

    protected void mergePlugin( Plugin target, Plugin source, boolean sourceDominant, Map<Object, Object> context )
    {
        mergeConfigurationContainer( target, source, sourceDominant, context );
        mergePlugin_GroupId( target, source, sourceDominant, context );
        mergePlugin_ArtifactId( target, source, sourceDominant, context );
        mergePlugin_Version( target, source, sourceDominant, context );
        mergePlugin_Extensions( target, source, sourceDominant, context );
        mergePlugin_Dependencies( target, source, sourceDominant, context );
        mergePlugin_Executions( target, source, sourceDominant, context );
    }

    protected void mergePlugin_GroupId( Plugin target, Plugin source, boolean sourceDominant,
                                        Map<Object, Object> context )
    {
        String src = source.getGroupId();
        if ( src != null )
        {
            if ( sourceDominant || target.getGroupId() == null )
            {
                target.setGroupId( src );
                target.setLocation( "groupId", source.getLocation( "groupId" ) );
            }
        }
    }

    protected void mergePlugin_ArtifactId( Plugin target, Plugin source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getArtifactId();
        if ( src != null )
        {
            if ( sourceDominant || target.getArtifactId() == null )
            {
                target.setArtifactId( src );
                target.setLocation( "artifactId", source.getLocation( "artifactId" ) );
            }
        }
    }

    protected void mergePlugin_Version( Plugin target, Plugin source, boolean sourceDominant,
                                        Map<Object, Object> context )
    {
        String src = source.getVersion();
        if ( src != null )
        {
            if ( sourceDominant || target.getVersion() == null )
            {
                target.setVersion( src );
                target.setLocation( "version", source.getLocation( "version" ) );
            }
        }
    }

    protected void mergePlugin_Extensions( Plugin target, Plugin source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getExtensions();
        if ( src != null )
        {
            if ( sourceDominant || target.getExtensions() == null )
            {
                target.setExtensions( src );
                target.setLocation( "extensions", source.getLocation( "extensions" ) );
            }
        }
    }

    protected void mergePlugin_Dependencies( Plugin target, Plugin source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        target.setDependencies( merge( target.getDependencies(), source.getDependencies(),
                                       sourceDominant, new DependencyKeyComputer() ) );
    }

    protected void mergePlugin_Executions( Plugin target, Plugin source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        target.setExecutions( merge( target.getExecutions(), source.getExecutions(),
                                     sourceDominant, new ExecutionKeyComputer() ) );
    }

    protected void mergeConfigurationContainer( ConfigurationContainer target, ConfigurationContainer source,
                                                boolean sourceDominant, Map<Object, Object> context )
    {
        mergeConfigurationContainer_Inherited( target, source, sourceDominant, context );
        mergeConfigurationContainer_Configuration( target, source, sourceDominant, context );
    }

    protected void mergeConfigurationContainer_Inherited( ConfigurationContainer target, ConfigurationContainer source,
                                                          boolean sourceDominant, Map<Object, Object> context )
    {
        String src = source.getInherited();
        if ( src != null )
        {
            if ( sourceDominant || target.getInherited() == null )
            {
                target.setInherited( src );
                target.setLocation( "inherited", source.getLocation( "inherited" ) );
            }
        }
    }

    protected void mergeConfigurationContainer_Configuration( ConfigurationContainer target,
                                                              ConfigurationContainer source, boolean sourceDominant,
                                                              Map<Object, Object> context )
    {
        Xpp3Dom src = (Xpp3Dom) source.getConfiguration();
        if ( src != null )
        {
            Xpp3Dom tgt = (Xpp3Dom) target.getConfiguration();
            if ( sourceDominant || tgt == null )
            {
                tgt = Xpp3Dom.mergeXpp3Dom( new Xpp3Dom( src ), tgt );
            }
            else
            {
                tgt = Xpp3Dom.mergeXpp3Dom( tgt, src );
            }
            target.setConfiguration( tgt );
        }
    }

    protected void mergePluginExecution( PluginExecution target, PluginExecution source, boolean sourceDominant,
                                         Map<Object, Object> context )
    {
        mergeConfigurationContainer( target, source, sourceDominant, context );
        mergePluginExecution_Id( target, source, sourceDominant, context );
        mergePluginExecution_Phase( target, source, sourceDominant, context );
        mergePluginExecution_Goals( target, source, sourceDominant, context );
    }

    protected void mergePluginExecution_Id( PluginExecution target, PluginExecution source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        String src = source.getId();
        if ( src != null )
        {
            if ( sourceDominant || target.getId() == null )
            {
                target.setId( src );
                target.setLocation( "id", source.getLocation( "id" ) );
            }
        }
    }

    protected void mergePluginExecution_Phase( PluginExecution target, PluginExecution source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        String src = source.getPhase();
        if ( src != null )
        {
            if ( sourceDominant || target.getPhase() == null )
            {
                target.setPhase( src );
                target.setLocation( "phase", source.getLocation( "phase" ) );
            }
        }
    }

    protected void mergePluginExecution_Goals( PluginExecution target, PluginExecution source, boolean sourceDominant,
                                               Map<Object, Object> context )
    {
        List<String> src = source.getGoals();
        if ( !src.isEmpty() )
        {
            List<String> tgt = target.getGoals();
            List<String> merged = new ArrayList<>( tgt.size() + src.size() );
            merged.addAll( tgt );
            merged.addAll( src );
            target.setGoals( merged );
        }
    }

    protected void mergeResource( Resource target, Resource source, boolean sourceDominant,
                                  Map<Object, Object> context )
    {
        mergeFileSet( target, source, sourceDominant, context );
        mergeResource_TargetPath( target, source, sourceDominant, context );
        mergeResource_Filtering( target, source, sourceDominant, context );
        mergeResource_MergeId( target, source, sourceDominant, context );
    }

    protected void mergeResource_TargetPath( Resource target, Resource source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        String src = source.getTargetPath();
        if ( src != null )
        {
            if ( sourceDominant || target.getTargetPath() == null )
            {
                target.setTargetPath( src );
                target.setLocation( "targetPath", source.getLocation( "targetPath" ) );
            }
        }
    }

    protected void mergeResource_Filtering( Resource target, Resource source, boolean sourceDominant,
                                            Map<Object, Object> context )
    {
        String src = source.getFiltering();
        if ( src != null )
        {
            if ( sourceDominant || target.getFiltering() == null )
            {
                target.setFiltering( src );
                target.setLocation( "filtering", source.getLocation( "filtering" ) );
            }
        }
    }

    protected void mergeResource_MergeId( Resource target, Resource source, boolean sourceDominant,
                                          Map<Object, Object> context )
    {
        String src = source.getMergeId();
        if ( src != null )
        {
            if ( sourceDominant || target.getMergeId() == null )
            {
                target.setMergeId( src );
            }
        }
    }

    protected void mergeFileSet( FileSet target, FileSet source, boolean sourceDominant, Map<Object, Object> context )
    {
        mergePatternSet( target, source, sourceDominant, context );
        mergeFileSet_Directory( target, source, sourceDominant, context );
    }

    protected void mergeFileSet_Directory( FileSet target, FileSet source, boolean sourceDominant,
                                           Map<Object, Object> context )
    {
        String src = source.getDirectory();
        if ( src != null )
        {
            if ( sourceDominant || target.getDirectory() == null )
            {
                target.setDirectory( src );
                target.setLocation( "directory", source.getLocation( "directory" ) );
            }
        }
    }

    protected void mergePatternSet( PatternSet target, PatternSet source, boolean sourceDominant,
                                    Map<Object, Object> context )
    {
        mergePatternSet_Includes( target, source, sourceDominant, context );
        mergePatternSet_Excludes( target, source, sourceDominant, context );
    }

    protected void mergePatternSet_Includes( PatternSet target, PatternSet source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        List<String> src = source.getIncludes();
        if ( !src.isEmpty() )
        {
            List<String> tgt = target.getIncludes();
            List<String> merged = new ArrayList<>( tgt.size() + src.size() );
            merged.addAll( tgt );
            merged.addAll( src );
            target.setIncludes( merged );
        }
    }

    protected void mergePatternSet_Excludes( PatternSet target, PatternSet source, boolean sourceDominant,
                                             Map<Object, Object> context )
    {
        List<String> src = source.getExcludes();
        if ( !src.isEmpty() )
        {
            List<String> tgt = target.getExcludes();
            List<String> merged = new ArrayList<>( tgt.size() + src.size() );
            merged.addAll( tgt );
            merged.addAll( src );
            target.setExcludes( merged );
        }
    }

    protected void mergeProfile( Profile target, Profile source, boolean sourceDominant, Map<Object, Object> context )
    {
        mergeModelBase( target, source, sourceDominant, context );
        // TODO
    }

    protected void mergeActivation( Activation target, Activation source, boolean sourceDominant,
                                    Map<Object, Object> context )
    {
        // TODO
    }

    protected Object getDependencyKey( Dependency dependency )
    {
        return dependency;
    }

    protected Object getPluginKey( Plugin plugin )
    {
        return plugin;
    }

    protected Object getPluginExecutionKey( PluginExecution pluginExecution )
    {
        return pluginExecution;
    }

    protected Object getReportPluginKey( ReportPlugin reportPlugin )
    {
        return reportPlugin;
    }

    protected Object getReportSetKey( ReportSet reportSet )
    {
        return reportSet;
    }

    protected Object getLicenseKey( License license )
    {
        return license;
    }

    protected Object getMailingListKey( MailingList mailingList )
    {
        return mailingList;
    }

    protected Object getDeveloperKey( Developer developer )
    {
        return developer;
    }

    protected Object getContributorKey( Contributor contributor )
    {
        return contributor;
    }

    protected Object getProfileKey( Profile profile )
    {
        return profile;
    }

    protected Object getRepositoryKey( Repository repository )
    {
        return getRepositoryBaseKey( repository );
    }

    protected Object getRepositoryBaseKey( RepositoryBase repositoryBase )
    {
        return repositoryBase;
    }

    protected Object getNotifierKey( Notifier notifier )
    {
        return notifier;
    }

    protected Object getResourceKey( Resource resource )
    {
        return resource;
    }

    protected Object getExtensionKey( Extension extension )
    {
        return extension;
    }

    protected Object getExclusionKey( Exclusion exclusion )
    {
        return exclusion;
    }

    /**
     * Use to compute keys for data structures
     * @param <T>
     */
    private interface KeyComputer<T>
    {
        Object key( T t );
    }

    /**
     * Remapping function
     * @param <T>
     */
    private interface Remapping<T>
    {
        T merge( T u, T v );
    }

    /**
     * KeyComputer for Dependency
     */
    private final class DependencyKeyComputer implements KeyComputer<Dependency>
    {
        @Override
        public Object key( Dependency dependency )
        {
            return getDependencyKey( dependency );
        }
    }

    /**
     * KeyComputer for License
     */
    private class LicenseKeyComputer implements KeyComputer<License>
    {
        @Override
        public Object key( License license )
        {
            return getLicenseKey( license );
        }
    }

    /**
     * KeyComputer for MailingList
     */
    private class MailingListKeyComputer implements KeyComputer<MailingList>
    {
        @Override
        public Object key( MailingList mailingList )
        {
            return getMailingListKey( mailingList );
        }
    }

    /**
     * KeyComputer for Developer
     */
    private class DeveloperKeyComputer implements KeyComputer<Developer>
    {
        @Override
        public Object key( Developer developer )
        {
            return getDeveloperKey( developer );
        }
    }

    /**
     * KeyComputer for Contributor
     */
    private class ContributorKeyComputer implements KeyComputer<Contributor>
    {
        @Override
        public Object key( Contributor contributor )
        {
            return getContributorKey( contributor );
        }
    }

    /**
     * KeyComputer for Profile
     */
    private class ProfileKeyComputer implements KeyComputer<Profile>
    {
        @Override
        public Object key( Profile profile )
        {
            return getProfileKey( profile );
        }
    }

    /**
     * KeyComputer for Repository
     */
    private class RepositoryKeyComputer implements KeyComputer<Repository>
    {
        @Override
        public Object key( Repository repository )
        {
            return getRepositoryKey( repository );
        }
    }

    /**
     * KeyComputer for ReportPlugin
     */
    private class ReportPluginKeyComputer implements KeyComputer<ReportPlugin>
    {
        @Override
        public Object key( ReportPlugin plugin )
        {
            return getReportPluginKey( plugin );
        }
    }

    /**
     * KeyComputer for Plugin
     */
    private class PluginKeyComputer implements KeyComputer<Plugin>
    {
        @Override
        public Object key( Plugin plugin )
        {
            return getPluginKey( plugin );
        }
    }

    /**
     * KeyComputer for ReportSet
     */
    private class ReportSetKeyComputer implements KeyComputer<ReportSet>
    {
        @Override
        public Object key( ReportSet reportSet )
        {
            return getReportSetKey( reportSet );
        }
    }

    /**
     * KeyComputer for Notifier
     */
    private class NotifierKeyComputer implements KeyComputer<Notifier>
    {
        @Override
        public Object key( Notifier notifier )
        {
            return getNotifierKey( notifier );
        }
    }

    /**
     * KeyComputer for Extension
     */
    private class ExtensionKeyComputer implements KeyComputer<Extension>
    {
        @Override
        public Object key( Extension extension )
        {
            return getExtensionKey( extension );
        }
    }

    /**
     * KeyComputer for Resource
     */
    private class ResourceKeyComputer implements KeyComputer<Resource>
    {
        @Override
        public Object key( Resource resource )
        {
            return getResourceKey( resource );
        }
    }

    /**
     * KeyComputer for PluginExecution
     */
    private class ExecutionKeyComputer implements KeyComputer<PluginExecution>
    {
        @Override
        public Object key( PluginExecution pluginExecution )
        {
            return getPluginExecutionKey( pluginExecution );
        }
    }

    /**
     * KeyComputer for Exclusion
     */
    private class ExclusionKeyComputer implements KeyComputer<Exclusion>
    {
        @Override
        public Object key( Exclusion exclusion )
        {
            return getExclusionKey( exclusion );
        }
    }

    /**
     * Return the second value if <code>sourceDominant</code> is true, the first one otherwise.
     * @param <T>
     */
    private static class SourceDominant<T> implements Remapping<T>
    {
        private final boolean sourceDominant;

        SourceDominant( boolean sourceDominant )
        {
            this.sourceDominant = sourceDominant;
        }

        @Override
        public T merge( T u, T v )
        {
            return sourceDominant ? v : u;
        }
    }

    /**
     * Merge two lists
     */
    private static <T> List<T> merge( List<T> tgt, List<T> src, boolean sourceDominant, KeyComputer<T> computer )
    {
        return merge( tgt, src, computer, new SourceDominant<T>( sourceDominant ) );
    }

    private static <T> List<T> merge( List<T> tgt, List<T> src, KeyComputer<T> computer, Remapping<T> remapping )
    {
        if ( src.isEmpty() )
        {
            return tgt;
        }

        MergingList<T> list;
        if ( tgt instanceof MergingList )
        {
            list = (MergingList<T>) tgt;
        }
        else
        {
            list = new MergingList<>( computer, src.size() + tgt.size() );
            list.mergeAll( tgt, new SourceDominant<T>( true ) );
        }

        list.mergeAll( src, remapping );
        return list;
    }

    /**
     * Merging list
     * @param <V>
     */
    private static class MergingList<V> extends AbstractList<V> implements java.io.Serializable
    {

        private final KeyComputer<V> keyComputer;
        private Map<Object, V> map;
        private List<V> list;

        MergingList( KeyComputer<V> keyComputer, int initialCapacity )
        {
            this.map = new LinkedHashMap<>( initialCapacity );
            this.keyComputer = keyComputer;
        }

        Object writeReplace() throws ObjectStreamException
        {
            return new ArrayList<>( this );
        }

        @Override
        public Iterator<V> iterator()
        {
            if ( map != null )
            {
                return map.values().iterator();
            }
            else
            {
                return list.iterator();
            }
        }

        void mergeAll( Collection<V> vs, Remapping<V> remapping )
        {
            if ( map == null )
            {
                map = new LinkedHashMap<>( list.size() + vs.size() );
                for ( V v : list )
                {
                    map.put( keyComputer.key( v ), v );
                }
                list = null;
            }
            if ( vs instanceof MergingList && ( (MergingList) vs ).map != null )
            {
                for ( Map.Entry<Object, V> e : ( (MergingList<V>) vs ).map.entrySet() )
                {
                    Object key = e.getKey();
                    V oldValue = map.get( key );
                    // JDK8: this should be a call to map.merge( key, v, remapping )
                    V newValue = ( oldValue == null ) ? e.getValue() : remapping.merge( oldValue, e.getValue() );
                    if ( newValue == null )
                    {
                        remove( key );
                    }
                    else if ( newValue != oldValue )
                    {
                        map.put( key, newValue );
                    }
                }
            }
            else
            {
                for ( V v : vs )
                {
                    Object key = keyComputer.key( v );
                    // JDK8: this should be a call to map.merge( key, v, remapping )
                    V oldValue = map.get( key );
                    V newValue = ( oldValue == null ) ? v : remapping.merge( oldValue, v );
                    if ( newValue == null )
                    {
                        remove( key );
                    }
                    else
                    {
                        map.put( key, newValue );
                    }
                }
            }
        }

        @Override
        public boolean contains( Object o )
        {
            if ( map != null )
            {
                return map.containsValue( o );
            }
            else
            {
                return list.contains( o );
            }
        }

        private List<V> asList()
        {
            if ( list == null )
            {
                list = new ArrayList<>( map.values() );
                map = null;
            }
            return list;
        }

        @Override
        public void add( int index, V element )
        {
            asList().add( index, element );
        }

        @Override
        public V remove( int index )
        {
            return asList().remove( index );
        }

        @Override
        public V get( int index )
        {
            return asList().get( index );
        }

        @Override
        public int size()
        {
            if ( map != null )
            {
                return map.size();
            }
            else
            {
                return list.size();
            }
        }
    }
}
