/*
* 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.LinkedList;
import java.util.List;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import org.apache.jmeter.engine.event.LoopIterationEvent;
import org.apache.jmeter.engine.event.LoopIterationListener;
import org.apache.jmeter.samplers.Sampler;
import org.apache.jmeter.testelement.AbstractTestElement;
import org.apache.jmeter.testelement.TestElement;
import org.apache.jmeter.threads.TestCompiler;
import org.apache.jmeter.threads.TestCompilerHelper;
import org.apache.jorphan.logging.LoggingManager;
import org.apache.log.Logger;
/**
* <p>
* This class is the basis for all the controllers.
* It also implements SimpleController.
* </p>
* <p>
* The main entry point is next(), which is called by by JMeterThread as follows:
* </p>
* <p>
* <code>while (running && (sampler = controller.next()) != null)</code>
* </p>
*/
public class GenericController extends AbstractTestElement implements Controller, Serializable, TestCompilerHelper {
private static final long serialVersionUID = 234L;
private static final Logger log = LoggingManager.getLoggerForClass();
private transient LinkedList<LoopIterationListener> iterationListeners =
new LinkedList<LoopIterationListener>();
// Only create the map if it is required
private transient final ConcurrentMap<TestElement, Object> children =
TestCompiler.IS_USE_STATIC_SET ? null : new ConcurrentHashMap<TestElement, Object>();
private static final Object DUMMY = new Object();
// May be replaced by RandomOrderController
protected transient List<TestElement> subControllersAndSamplers =
new ArrayList<TestElement>();
/**
* Index of current sub controller or sampler
*/
protected transient int current;
/**
* TODO document this
*/
private transient int iterCount;
/**
* Controller has ended
*/
private transient boolean done;
/**
* First sampler or sub-controller
*/
private transient boolean first;
/**
* Creates a Generic Controller
*/
public GenericController() {
}
@Override
public void initialize() {
resetCurrent();
resetIterCount();
done = false; // TODO should this use setDone()?
first = true; // TODO should this use setFirst()?
TestElement elem;
for (int i = 0; i < subControllersAndSamplers.size(); i++) {
elem = subControllersAndSamplers.get(i);
if (elem instanceof Controller) {
((Controller) elem).initialize();
}
}
}
/**
* Resets the controller:
* <ul>
* <li>resetCurrent() (i.e. current=0)</li>
* <li>increment iteration count</li>
* <li>sets first=true</li>
* <li>recoverRunningVersion() to set the controller back to the initial state</li>
* </ul>
*
*/
protected void reInitialize() {
resetCurrent();
incrementIterCount();
setFirst(true);
recoverRunningVersion();
}
/**
* <p>
* Determines the next sampler to be processed.
* </p>
*
* <p>
* If isDone, returns null.
* </p>
*
* <p>
* Gets the list element using current pointer.
* If this is null, calls {@link #nextIsNull()}.
* </p>
*
* <p>
* If the list element is a sampler, calls {@link #nextIsASampler(Sampler)},
* otherwise calls {@link #nextIsAController(Controller)}
* </p>
*
* <p>
* If any of the called methods throws NextIsNullException, returns null,
* otherwise the value obtained above is returned.
* </p>
*
* @return the next sampler or null
*/
@Override
public Sampler next() {
fireIterEvents();
if (log.isDebugEnabled()) {
log.debug("Calling next on: " + this.getClass().getName());
}
if (isDone()) {
return null;
}
Sampler returnValue = null;
try {
TestElement currentElement = getCurrentElement();
setCurrentElement(currentElement);
if (currentElement == null) {
// incrementCurrent();
returnValue = nextIsNull();
} else {
if (currentElement instanceof Sampler) {
returnValue = nextIsASampler((Sampler) currentElement);
} else { // must be a controller
returnValue = nextIsAController((Controller) currentElement);
}
}
} catch (NextIsNullException e) {
// NOOP
}
return returnValue;
}
/**
* @see org.apache.jmeter.control.Controller#isDone()
*/
@Override
public boolean isDone() {
return done;
}
protected void setDone(boolean done) {
this.done = done;
}
protected boolean isFirst() {
return first;
}
public void setFirst(boolean b) {
first = b;
}
/**
* Called by next() if the element is a Controller,
* and returns the next sampler from the controller.
* If this is null, then updates the current pointer and makes recursive call to next().
* @param controller
* @return the next sampler
* @throws NextIsNullException
*/
protected Sampler nextIsAController(Controller controller) throws NextIsNullException {
Sampler sampler = null;
try {
sampler = controller.next();
} catch (StackOverflowError soe) {
// See bug 50618 Catches a StackOverflowError when a condition returns
// always false (after at least one iteration with return true)
log.warn("StackOverflowError detected"); // $NON-NLS-1$
throw new NextIsNullException("StackOverflowError detected", soe);
}
if (sampler == null) {
currentReturnedNull(controller);
sampler = next();
}
return sampler;
}
/**
* Increment the current pointer and return the element.
* Called by next() if the element is a sampler.
* (May be overriden by sub-classes).
*
* @param element
* @return input element
* @throws NextIsNullException
*/
protected Sampler nextIsASampler(Sampler element) throws NextIsNullException {
incrementCurrent();
return element;
}
/**
* Called by next() when getCurrentElement() returns null.
* Reinitialises the controller.
*
* @return null (always, for this class)
* @throws NextIsNullException
*/
protected Sampler nextIsNull() throws NextIsNullException {
reInitialize();
return null;
}
/**
* {@inheritDoc}
*/
@Override
public void triggerEndOfLoop() {
reInitialize();
}
/**
* Called to re-initialize a index of controller's elements (Bug 50032)
*
*/
protected void reInitializeSubController() {
boolean wasFlagSet = getThreadContext().setIsReinitializingSubControllers();
try {
TestElement currentElement = getCurrentElement();
if (currentElement != null) {
if (currentElement instanceof Sampler) {
nextIsASampler((Sampler) currentElement);
} else { // must be a controller
if (nextIsAController((Controller) currentElement) != null) {
reInitializeSubController();
}
}
}
} catch (NextIsNullException e) {
// NOOP
} finally {
if (wasFlagSet) {
getThreadContext().unsetIsReinitializingSubControllers();
}
}
}
/**
* If the controller is done, remove it from the list,
* otherwise increment to next entry in list.
*
* @param c controller
*/
protected void currentReturnedNull(Controller c) {
if (c.isDone()) {
removeCurrentElement();
} else {
incrementCurrent();
}
}
/**
* Gets the SubControllers attribute of the GenericController object
*
* @return the SubControllers value
*/
protected List<TestElement> getSubControllers() {
return subControllersAndSamplers;
}
private void addElement(TestElement child) {
subControllersAndSamplers.add(child);
}
/**
* Empty implementation - does nothing.
*
* @param currentElement
* @throws NextIsNullException
*/
protected void setCurrentElement(TestElement currentElement) throws NextIsNullException {
}
/**
* <p>
* Gets the element indicated by the <code>current</code> index, if one exists,
* from the <code>subControllersAndSamplers</code> list.
* </p>
* <p>
* If the <code>subControllersAndSamplers</code> list is empty,
* then set done = true, and throw NextIsNullException.
* </p>
* @return the current element - or null if current index too large
* @throws NextIsNullException if list is empty
*/
protected TestElement getCurrentElement() throws NextIsNullException {
if (current < subControllersAndSamplers.size()) {
return subControllersAndSamplers.get(current);
}
if (subControllersAndSamplers.size() == 0) {
setDone(true);
throw new NextIsNullException();
}
return null;
}
protected void removeCurrentElement() {
subControllersAndSamplers.remove(current);
}
/**
* Increments the current pointer; called by currentReturnedNull to move the
* controller on to its next child.
*/
protected void incrementCurrent() {
current++;
}
protected void resetCurrent() {
current = 0;
}
@Override
public void addTestElement(TestElement child) {
if (child instanceof Controller || child instanceof Sampler) {
addElement(child);
}
}
/**
* {@inheritDoc}
*/
@Override
public final boolean addTestElementOnce(TestElement child){
if (children.putIfAbsent(child, DUMMY) == null) {
addTestElement(child);
return true;
}
return false;
}
@Override
public void addIterationListener(LoopIterationListener lis) {
/*
* A little hack - add each listener to the start of the list - this
* ensures that the thread running the show is the first listener and
* can modify certain values before other listeners are called.
*/
iterationListeners.addFirst(lis);
}
/**
* Remove listener
*/
@Override
public void removeIterationListener(LoopIterationListener iterationListener) {
for (Iterator<LoopIterationListener> iterator = iterationListeners.iterator(); iterator.hasNext();) {
LoopIterationListener listener = iterator.next();
if(listener == iterationListener)
{
iterator.remove();
break; // can only match once
}
}
}
protected void fireIterEvents() {
if (isFirst()) {
fireIterationStart();
first = false; // TODO - should this use setFirst() ?
}
}
protected void fireIterationStart() {
LoopIterationEvent event = new LoopIterationEvent(this, getIterCount());
for (LoopIterationListener item : iterationListeners) {
item.iterationStart(event);
}
}
protected int getIterCount() {
return iterCount;
}
protected void incrementIterCount() {
iterCount++;
}
protected void resetIterCount() {
iterCount = 0;
}
}