/**
* 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.hadoop.test;
import java.io.File;
import java.io.IOException;
import java.io.StringWriter;
import java.lang.management.ManagementFactory;
import java.lang.management.ThreadInfo;
import java.lang.management.ThreadMXBean;
import java.lang.reflect.InvocationTargetException;
import java.util.Arrays;
import java.util.Random;
import java.util.Set;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.regex.Pattern;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.impl.Log4JLogger;
import org.apache.hadoop.fs.FileUtil;
import org.apache.hadoop.util.StringUtils;
import org.apache.hadoop.util.Time;
import org.apache.log4j.Layout;
import org.apache.log4j.Logger;
import org.apache.log4j.WriterAppender;
import org.junit.Assert;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;
import com.google.common.base.Joiner;
import com.google.common.base.Supplier;
import com.google.common.collect.Sets;
/**
* Test provides some very generic helpers which might be used across the tests
*/
public abstract class GenericTestUtils {
private static final AtomicInteger sequence = new AtomicInteger();
/**
* Extracts the name of the method where the invocation has happened
* @return String name of the invoking method
*/
public static String getMethodName() {
return Thread.currentThread().getStackTrace()[2].getMethodName();
}
/**
* Generates a process-wide unique sequence number.
* @return an unique sequence number
*/
public static int uniqueSequenceId() {
return sequence.incrementAndGet();
}
/**
* Assert that a given file exists.
*/
public static void assertExists(File f) {
Assert.assertTrue("File " + f + " should exist", f.exists());
}
/**
* List all of the files in 'dir' that match the regex 'pattern'.
* Then check that this list is identical to 'expectedMatches'.
* @throws IOException if the dir is inaccessible
*/
public static void assertGlobEquals(File dir, String pattern,
String ... expectedMatches) throws IOException {
Set<String> found = Sets.newTreeSet();
for (File f : FileUtil.listFiles(dir)) {
if (f.getName().matches(pattern)) {
found.add(f.getName());
}
}
Set<String> expectedSet = Sets.newTreeSet(
Arrays.asList(expectedMatches));
Assert.assertEquals("Bad files matching " + pattern + " in " + dir,
Joiner.on(",").join(expectedSet),
Joiner.on(",").join(found));
}
public static void assertExceptionContains(String string, Throwable t) {
String msg = t.getMessage();
Assert.assertTrue(
"Expected to find '" + string + "' but got unexpected exception:"
+ StringUtils.stringifyException(t), msg.contains(string));
}
public static void waitFor(Supplier<Boolean> check,
int checkEveryMillis, int waitForMillis)
throws TimeoutException, InterruptedException
{
long st = Time.now();
do {
boolean result = check.get();
if (result) {
return;
}
Thread.sleep(checkEveryMillis);
} while (Time.now() - st < waitForMillis);
throw new TimeoutException("Timed out waiting for condition. " +
"Thread diagnostics:\n" +
TimedOutTestsListener.buildThreadDiagnosticString());
}
public static class LogCapturer {
private StringWriter sw = new StringWriter();
private WriterAppender appender;
private Logger logger;
public static LogCapturer captureLogs(Log l) {
Logger logger = ((Log4JLogger)l).getLogger();
LogCapturer c = new LogCapturer(logger);
return c;
}
private LogCapturer(Logger logger) {
this.logger = logger;
Layout layout = Logger.getRootLogger().getAppender("stdout").getLayout();
WriterAppender wa = new WriterAppender(layout, sw);
logger.addAppender(wa);
}
public String getOutput() {
return sw.toString();
}
public void stopCapturing() {
logger.removeAppender(appender);
}
}
/**
* Mockito answer helper that triggers one latch as soon as the
* method is called, then waits on another before continuing.
*/
public static class DelayAnswer implements Answer<Object> {
private final Log LOG;
private final CountDownLatch fireLatch = new CountDownLatch(1);
private final CountDownLatch waitLatch = new CountDownLatch(1);
private final CountDownLatch resultLatch = new CountDownLatch(1);
private final AtomicInteger fireCounter = new AtomicInteger(0);
private final AtomicInteger resultCounter = new AtomicInteger(0);
// Result fields set after proceed() is called.
private volatile Throwable thrown;
private volatile Object returnValue;
public DelayAnswer(Log log) {
this.LOG = log;
}
/**
* Wait until the method is called.
*/
public void waitForCall() throws InterruptedException {
fireLatch.await();
}
/**
* Tell the method to proceed.
* This should only be called after waitForCall()
*/
public void proceed() {
waitLatch.countDown();
}
@Override
public Object answer(InvocationOnMock invocation) throws Throwable {
LOG.info("DelayAnswer firing fireLatch");
fireCounter.getAndIncrement();
fireLatch.countDown();
try {
LOG.info("DelayAnswer waiting on waitLatch");
waitLatch.await();
LOG.info("DelayAnswer delay complete");
} catch (InterruptedException ie) {
throw new IOException("Interrupted waiting on latch", ie);
}
return passThrough(invocation);
}
protected Object passThrough(InvocationOnMock invocation) throws Throwable {
try {
Object ret = invocation.callRealMethod();
returnValue = ret;
return ret;
} catch (Throwable t) {
thrown = t;
throw t;
} finally {
resultCounter.incrementAndGet();
resultLatch.countDown();
}
}
/**
* After calling proceed(), this will wait until the call has
* completed and a result has been returned to the caller.
*/
public void waitForResult() throws InterruptedException {
resultLatch.await();
}
/**
* After the call has gone through, return any exception that
* was thrown, or null if no exception was thrown.
*/
public Throwable getThrown() {
return thrown;
}
/**
* After the call has gone through, return the call's return value,
* or null in case it was void or an exception was thrown.
*/
public Object getReturnValue() {
return returnValue;
}
public int getFireCount() {
return fireCounter.get();
}
public int getResultCount() {
return resultCounter.get();
}
}
/**
* An Answer implementation that simply forwards all calls through
* to a delegate.
*
* This is useful as the default Answer for a mock object, to create
* something like a spy on an RPC proxy. For example:
* <code>
* NamenodeProtocol origNNProxy = secondary.getNameNode();
* NamenodeProtocol spyNNProxy = Mockito.mock(NameNodeProtocol.class,
* new DelegateAnswer(origNNProxy);
* doThrow(...).when(spyNNProxy).getBlockLocations(...);
* ...
* </code>
*/
public static class DelegateAnswer implements Answer<Object> {
private final Object delegate;
private final Log log;
public DelegateAnswer(Object delegate) {
this(null, delegate);
}
public DelegateAnswer(Log log, Object delegate) {
this.log = log;
this.delegate = delegate;
}
@Override
public Object answer(InvocationOnMock invocation) throws Throwable {
try {
if (log != null) {
log.info("Call to " + invocation + " on " + delegate,
new Exception("TRACE"));
}
return invocation.getMethod().invoke(
delegate, invocation.getArguments());
} catch (InvocationTargetException ite) {
throw ite.getCause();
}
}
}
/**
* An Answer implementation which sleeps for a random number of milliseconds
* between 0 and a configurable value before delegating to the real
* implementation of the method. This can be useful for drawing out race
* conditions.
*/
public static class SleepAnswer implements Answer<Object> {
private final int maxSleepTime;
private static Random r = new Random();
public SleepAnswer(int maxSleepTime) {
this.maxSleepTime = maxSleepTime;
}
@Override
public Object answer(InvocationOnMock invocation) throws Throwable {
boolean interrupted = false;
try {
Thread.sleep(r.nextInt(maxSleepTime));
} catch (InterruptedException ie) {
interrupted = true;
}
try {
return invocation.callRealMethod();
} finally {
if (interrupted) {
Thread.currentThread().interrupt();
}
}
}
}
public static void assertMatches(String output, String pattern) {
Assert.assertTrue("Expected output to match /" + pattern + "/" +
" but got:\n" + output,
Pattern.compile(pattern).matcher(output).find());
}
public static void assertValueNear(long expected, long actual, long allowedError) {
assertValueWithinRange(expected - allowedError, expected + allowedError, actual);
}
public static void assertValueWithinRange(long expectedMin, long expectedMax,
long actual) {
Assert.assertTrue("Expected " + actual + " to be in range (" + expectedMin + ","
+ expectedMax + ")", expectedMin <= actual && actual <= expectedMax);
}
/**
* Assert that there are no threads running whose name matches the
* given regular expression.
* @param regex the regex to match against
*/
public static void assertNoThreadsMatching(String regex) {
Pattern pattern = Pattern.compile(regex);
ThreadMXBean threadBean = ManagementFactory.getThreadMXBean();
ThreadInfo[] infos = threadBean.getThreadInfo(threadBean.getAllThreadIds(), 20);
for (ThreadInfo info : infos) {
if (info == null) continue;
if (pattern.matcher(info.getThreadName()).matches()) {
Assert.fail("Leaked thread: " + info + "\n" +
Joiner.on("\n").join(info.getStackTrace()));
}
}
}
}