/*******************************************************************************
* Copyright (c) 2007, 2010 Oracle. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0, which accompanies this distribution
* and is available at http://www.eclipse.org/legal/epl-v10.html.
*
* Contributors:
* Oracle - initial API and implementation
******************************************************************************/
package org.eclipse.jpt.common.utility.tests.internal;
import org.eclipse.jpt.common.utility.internal.SynchronizedObject;
@SuppressWarnings("nls")
public class SynchronizedObjectTests
extends MultiThreadedTestCase
{
private volatile SynchronizedObject<Object> so;
volatile boolean timeoutOccurred;
volatile Object value = new Object();
volatile long startTime;
volatile long endTime;
volatile Object soValue;
public SynchronizedObjectTests(String name) {
super(name);
}
@Override
protected void setUp() throws Exception {
super.setUp();
this.so = new SynchronizedObject<Object>();
this.timeoutOccurred = false;
this.startTime = 0;
this.endTime = 0;
this.soValue = null;
}
public void testAccessors() throws Exception {
this.so.setValue(null);
assertNull(this.so.getValue());
assertFalse(this.so.isNotNull());
assertTrue(this.so.isNull());
this.so.setValue(this.value);
assertEquals(this.value, this.so.getValue());
assertTrue(this.so.isNotNull());
assertFalse(this.so.isNull());
this.so.setNull();
assertNull(this.so.getValue());
assertFalse(this.so.isNotNull());
assertTrue(this.so.isNull());
assertSame(this.so, this.so.getMutex());
}
/**
* t2 will wait indefinitely until t1 sets the value to null
*/
public void testWaitUntilNull() throws Exception {
this.verifyWaitUntilNull(0);
// no timeout occurs...
assertFalse(this.timeoutOccurred);
// ...and the value should be set to null by t2
assertNull(this.so.getValue());
// make a reasonable guess about how long t2 took
long time = this.calculateElapsedTime();
assertTrue("t2 finished a bit early (expected value should be > " + TICK + "): " + time, time > TICK);
}
/**
* t2 will time out waiting for t1 to set the value to null
*/
public void testWaitUntilNullTimeout() throws Exception {
this.verifyWaitUntilNull(TICK);
// timeout occurs...
assertTrue(this.timeoutOccurred);
// ...and the value will eventually be set to null by t1
assertNull(this.so.getValue());
// make a reasonable guess about how long t2 took
long time = this.calculateElapsedTime();
assertTrue("t2 finished a bit late (expected value should be < " + THREE_TICKS + "): " + time, time < THREE_TICKS);
}
private void verifyWaitUntilNull(long t2Timeout) throws Exception {
this.executeThreads(this.buildSetNullCommand(), this.buildWaitUntilNullCommand(t2Timeout));
}
/**
* t2 will wait indefinitely until t1 sets the value to null;
* then t2 will set the value to an object
*/
public void testWaitToSetValue() throws Exception {
this.verifyWaitToSetValue(0);
// no timeout occurs...
assertFalse(this.timeoutOccurred);
// ...and the value should be set to an object by t2
assertTrue(this.so.isNotNull());
// make a reasonable guess about how long t2 took
long time = this.calculateElapsedTime();
assertTrue("t2 finished a bit early (expected value should be > " + TICK + "): " + time, time > TICK);
}
/**
* t2 will time out waiting for t1 to set the value to null
*/
public void testWaitToSetValueTimeout() throws Exception {
this.verifyWaitToSetValue(TICK);
// timeout occurs...
assertTrue(this.timeoutOccurred);
// ...and the value will eventually be set to null by t1
assertTrue(this.so.isNull());
// make a reasonable guess about how long t2 took
long time = this.calculateElapsedTime();
assertTrue("t2 finished a bit late (expected value should be < " + THREE_TICKS + "): " + time, time < THREE_TICKS);
}
private void verifyWaitToSetValue(long t2Timeout) throws Exception {
this.executeThreads(this.buildSetNullCommand(), this.buildWaitToSetValueCommand(t2Timeout));
}
/**
* t2 will wait until t1 is finished "initializing" the value;
* then t2 will get the newly-initialized value ("foo")
*/
public void testExecute() throws Exception {
this.so.setValue(null);
Runnable r1 = this.buildRunnable(this.buildInitializeValueCommand(), this.so, 0);
// give t1 a head start of 100 ms
Runnable r2 = this.buildRunnable(this.buildGetValueCommand(), this.so, TICK);
Thread t1 = this.buildThread(r1);
Thread t2 = this.buildThread(r2);
t1.start();
t2.start();
t1.join();
t2.join();
assertEquals("foo", this.so.getValue());
assertEquals("foo", this.soValue);
// make a reasonable guess about how long t2 took
long time = this.calculateElapsedTime();
assertTrue("t2 finished a bit early (expected value should be > " + TWO_TICKS + "): " + time, time > TWO_TICKS);
}
private void executeThreads(Command t1Command, Command t2Command) throws Exception {
this.so.setValue(this.value);
Runnable r1 = this.buildRunnable(t1Command, this.so, TWO_TICKS);
Runnable r2 = this.buildRunnable(t2Command, this.so, 0);
Thread t1 = this.buildThread(r1);
Thread t2 = this.buildThread(r2);
t1.start();
t2.start();
t1.join();
t2.join();
}
private Command buildSetNullCommand() {
return new Command() {
public void execute(SynchronizedObject<Object> sObject) {
sObject.setNull();
}
};
}
private Command buildWaitUntilNullCommand(final long timeout) {
return new Command() {
public void execute(SynchronizedObject<Object> sObject) throws InterruptedException {
SynchronizedObjectTests.this.startTime = System.currentTimeMillis();
SynchronizedObjectTests.this.timeoutOccurred = ! sObject.waitUntilNull(timeout);
SynchronizedObjectTests.this.endTime = System.currentTimeMillis();
}
};
}
private Command buildWaitToSetValueCommand(final long timeout) {
return new Command() {
public void execute(SynchronizedObject<Object> sObject) throws InterruptedException {
SynchronizedObjectTests.this.startTime = System.currentTimeMillis();
SynchronizedObjectTests.this.timeoutOccurred = ! sObject.waitToSetValue(SynchronizedObjectTests.this.value, timeout);
SynchronizedObjectTests.this.endTime = System.currentTimeMillis();
}
};
}
private Command buildInitializeValueCommand() {
return new Command() {
public void execute(final SynchronizedObject<Object> sObject) throws InterruptedException {
sObject.execute(
new org.eclipse.jpt.common.utility.Command() {
public void execute() {
// pretend to perform some long initialization process
try {
Thread.sleep(5 * TICK);
} catch (Exception ex) {
throw new RuntimeException(ex);
}
sObject.setValue("foo");
}
}
);
}
};
}
private Command buildGetValueCommand() {
return new Command() {
public void execute(SynchronizedObject<Object> sObject) throws InterruptedException {
SynchronizedObjectTests.this.startTime = System.currentTimeMillis();
SynchronizedObjectTests.this.soValue = sObject.getValue();
SynchronizedObjectTests.this.endTime = System.currentTimeMillis();
}
};
}
private Runnable buildRunnable(final Command command, final SynchronizedObject<Object> sObject, final long sleep) {
return new TestRunnable() {
@Override
protected void run_() throws InterruptedException {
if (sleep != 0) {
Thread.sleep(sleep);
}
command.execute(sObject);
}
};
}
private long calculateElapsedTime() {
return this.endTime - this.startTime;
}
// ********** Command interface **********
private interface Command {
void execute(SynchronizedObject<Object> so) throws InterruptedException;
}
}
