org.apache.hadoop.util.ThreadUtil Maven / Gradle / Ivy
/*
* 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.util;
import org.apache.hadoop.classification.InterfaceStability;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.io.InputStream;
@InterfaceStability.Evolving
public class ThreadUtil {
private static final Logger LOG = LoggerFactory.getLogger(ThreadUtil.class);
/**
* Cause the current thread to sleep as close as possible to the provided
* number of milliseconds. This method will log and ignore any
* {@link InterruptedException} encountered.
*
* @param millis the number of milliseconds for the current thread to sleep
*/
public static void sleepAtLeastIgnoreInterrupts(long millis) {
long start = Time.now();
while (Time.now() - start < millis) {
long timeToSleep = millis -
(Time.now() - start);
try {
Thread.sleep(timeToSleep);
} catch (InterruptedException ie) {
LOG.warn("interrupted while sleeping", ie);
}
}
}
/**
* Join a thread as uninterruptible.
* The call continues to block until the result is available even when the
* caller thread is interrupted.
* The method will log any {@link InterruptedException} then will re-interrupt
* the thread.
*
* @param toJoin the thread to Join on.
*/
public static void joinUninterruptibly(Thread toJoin) {
boolean interrupted = false;
try {
while (true) {
try {
toJoin.join();
return;
} catch (InterruptedException e) {
interrupted = true;
LOG.warn("interrupted while sleeping", e);
}
}
} finally {
if (interrupted) {
Thread.currentThread().interrupt();
}
}
}
/**
* Convenience method that returns a resource as inputstream from the
* classpath.
*
* Uses the Thread's context classloader to load resource.
*
* @param resourceName resource to retrieve.
*
* @throws IOException thrown if resource cannot be loaded
* @return inputstream with the resource.
*/
public static InputStream getResourceAsStream(String resourceName)
throws IOException {
ClassLoader cl = Thread.currentThread().getContextClassLoader();
if (cl == null) {
throw new IOException("Can not read resource file '" + resourceName +
"' because class loader of the current thread is null");
}
return getResourceAsStream(cl, resourceName);
}
/**
* Convenience method that returns a resource as inputstream from the
* classpath using given classloader.
*
*
* @param cl ClassLoader to be used to retrieve resource.
* @param resourceName resource to retrieve.
*
* @throws IOException thrown if resource cannot be loaded
* @return inputstream with the resource.
*/
public static InputStream getResourceAsStream(ClassLoader cl,
String resourceName)
throws IOException {
if (cl == null) {
throw new IOException("Can not read resource file '" + resourceName +
"' because given class loader is null");
}
InputStream is = cl.getResourceAsStream(resourceName);
if (is == null) {
throw new IOException("Can not read resource file '" +
resourceName + "'");
}
return is;
}
}