JMeter example source code file (RandomOrderController.java)

This example JMeter source code file (RandomOrderController.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - JMeter tags/keywords

genericcontroller, io, iterator, iterator, list, override, override, randomordercontroller, randomordercontroller, serializable, serializable, util

The JMeter RandomOrderController.java source code

/*
 * 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.
 */
package org.apache.jmeter.control;

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

import org.apache.jmeter.testelement.TestElement;

/**
 * A controller that runs its children each at most once, but in a random order.
 *
 */
public class RandomOrderController extends GenericController implements Serializable {

    private static final long serialVersionUID = 240L;

    /**
     * Create a new RandomOrderController.
     */
    public RandomOrderController() {
    }

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

    /**
     * @see GenericController#reInitialize()
     */
    @Override
    protected 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<TestElement> 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<TestElement> 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;
    }
}