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package org.glassfish.jersey.client.rx.spi;

import java.util.concurrent.ExecutorService;

import javax.ws.rs.ConstrainedTo;
import javax.ws.rs.RuntimeType;
import javax.ws.rs.client.Invocation;

import org.glassfish.jersey.spi.Contract;

/**
 * Client-provider interface for creating {@link org.glassfish.jersey.client.rx.RxInvoker reactive invoker} instances.
 *
 * If supported by the provider, an invoker instance of the requested Java type will be created.
 * <p/>
 * A provider shall support a one-to-one mapping between a type, provided the type is not {@link Object}. A provider may also
 * support mapping of sub-types of a type (provided the type is not {@code Object}). It is expected that each provider supports
 * mapping for distinct set of types and subtypes so that different providers do not conflict with each other.
 * <p/>
 * An implementation can identify itself by placing a Java service provider configuration file (if not already present) -
 * {@code org.glassfish.jersey.client.rx.spi.RxInvokerProvider} - in the resource directory {@code META-INF/services}, and adding
 * the fully qualified service-provider-class of the implementation in the file.
 *
 * @author Michal Gajdos (michal.gajdos at oracle.com)
 * @since 2.13
 */
@Contract
@ConstrainedTo(RuntimeType.CLIENT)
public interface RxInvokerProvider {

    /**
     * Create an invoker of a given type.
     *
     * @param invokerType the invoker type.
     * @param builder     the builder to create JAX-RS {@link javax.ws.rs.client.Invocation invocation} invoked in reactive way.
     * @param executor    the executor service to execute reactive requests.
     * @param <RX>        the concrete reactive invocation type.
     * @return the invoker, otherwise {@code null} if the provider does not support the requested {@code type}.
     * @throws javax.ws.rs.ProcessingException if there is an error creating the invoker.
     */
    public <RX> RX getInvoker(Class<RX> invokerType, Invocation.Builder builder, ExecutorService executor);
}
