// $Header: /home/cvs/jakarta-jmeter/src/components/org/apache/jmeter/control/RandomOrderController.java,v 1.4 2004/02/19 00:04:35 sebb Exp $
/*
 * Copyright 2004 The Apache Software Foundation
 *
 * Licensed 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.
 */
package org.apache.jmeter.control;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import junit.framework.TestSuite;

import org.apache.jmeter.junit.JMeterTestCase;
import org.apache.jmeter.junit.stubs.TestSampler;
import org.apache.jmeter.testelement.TestElement;

/**
 * A controller that runs its children each at most once, but in a random order.
 *
 * @author  Mike Verdone
 * @version $Revision: 1.4 $ updated on $Date: 2004/02/19 00:04:35 $
 */
public class RandomOrderController
    extends GenericController
    implements Serializable
{
    /**
     * Create a new RandomOrderController.
     */
    public RandomOrderController()
    {
    }

    /**
     * @see GenericController#initialize()
     */ 
    public void initialize()
    {
        super.initialize();
        this.reorder();
    }

    /**
     * @see GenericController#reInitialize()
     */     
    public void reInitialize()
    {
        super.reInitialize();
        this.reorder();
    }
    
    /**
     * Replace the subControllersAndSamplers list with a reordered ArrayList.
     */
    private void reorder()
    {
        int numElements = this.subControllersAndSamplers.size();
        
        // Create a new list containing numElements null elements.
        List reordered = new ArrayList(this.subControllersAndSamplers.size());
        for (int i = 0; i < numElements; i++)
        {
            reordered.add(null);
        }

        // Insert the subControllersAndSamplers into random list positions.
        for (Iterator i = this.subControllersAndSamplers.iterator();
             i.hasNext(); )
        {
            int idx = (int)Math.floor(Math.random() * reordered.size());
            while (true)
            {
                if (idx == numElements)
                {
                    idx = 0;
                }
                if (reordered.get(idx) == null)
                {
                    reordered.set(idx, i.next());
                    break;
                }
                idx++;
            }
        }
        
        // Replace subControllersAndSamplers with reordered copy.
        this.subControllersAndSamplers = reordered;
    }

    public static class Test extends JMeterTestCase
    {

        public Test(String name)
        {
            super(name);
        }
        
        public void testRandomOrder()
        {
            testLog.debug("Testing RandomOrderController");
            RandomOrderController roc = new RandomOrderController();
            roc.addTestElement(new TestSampler("zero"));
            roc.addTestElement(new TestSampler("one"));
            roc.addTestElement(new TestSampler("two"));
            roc.addTestElement(new TestSampler("three"));
            TestElement sampler = null;
            List usedSamplers = new ArrayList();
            roc.initialize();
            while ((sampler = roc.next()) != null)
            {
                String samplerName = sampler.getPropertyAsString(TestSampler.NAME);
                if (usedSamplers.contains(samplerName))
                {
                    assertTrue("Duplicate sampler returned from next()", false);
                }
                usedSamplers.add(samplerName);
            }
            assertTrue("All samplers were returned",
                usedSamplers.size() == 4);
        }
        
        public void testRandomOrderNoElements()
        {
            RandomOrderController roc = new RandomOrderController();
            roc.initialize();
            assertTrue(roc.next() == null);
        }

        public void testRandomOrderOneElement()
        {
            RandomOrderController roc = new RandomOrderController();
            roc.addTestElement(new TestSampler("zero"));
            TestElement sampler = null;
            List usedSamplers = new ArrayList();
            roc.initialize();
            while ((sampler = roc.next()) != null)
            {
                String samplerName = sampler.getPropertyAsString(TestSampler.NAME);
                if (usedSamplers.contains(samplerName))
                {
                    assertTrue("Duplicate sampler returned from next()", false);
                }
                usedSamplers.add(samplerName);
            }
            assertTrue("All samplers were returned",
                usedSamplers.size() == 1);
        }
    }

    public static void main(String args[])
    {
        junit.textui.TestRunner.run(suite());
    }

    public static TestSuite suite()
    {
        TestSuite suite = new TestSuite();
        suite.addTest(new Test("testRandomOrderController"));
        return suite;
    }

}