/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2009, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
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 */
package org.jboss.modcluster.load.metric;

import org.jboss.modcluster.load.metric.impl.DeterministicLoadStateImpl;
import org.junit.Assert;
import org.junit.Test;

/**
 * @author Paul Ferraro
 * 
 */
public class DeterministicLoadMetricTestCase {
    private DeterministicLoadStateImpl state = new DeterministicLoadStateImpl();

    @Test
    public void testDelta() throws InterruptedException {
        long lastTime = this.state.getPreviousTime();

        Thread.sleep(500);

        double result = this.state.delta(20);

        long nextTime = this.state.getPreviousTime();

        double elapsed = (nextTime - lastTime) / 1000d;

        Assert.assertEquals(20 / elapsed, result, 0);

        lastTime = this.state.getPreviousTime();

        Thread.sleep(1000);

        result = this.state.delta(50);

        nextTime = this.state.getPreviousTime();

        elapsed = (nextTime - lastTime) / 1000d;

        Assert.assertEquals(30 / elapsed, result, 0);
    }
}
