hbase-common/src/main/java/org/apache/hadoop/hbase/util/HasThread.java

/**
 * 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.hbase.util;

import java.lang.Thread.UncaughtExceptionHandler;

import org.apache.yetus.audience.InterfaceAudience;

/**
 * Abstract class which contains a Thread and delegates the common Thread
 * methods to that instance.
 * 
 * The purpose of this class is to workaround Sun JVM bug #6915621, in which
 * something internal to the JDK uses Thread.currentThread() as a monitor
 * lock. This can produce deadlocks like HBASE-4367, HBASE-4101, etc.
 */
@InterfaceAudience.Private
public abstract class HasThread implements Runnable {
  private final Thread thread;
  
  public HasThread() {
    this.thread = new Thread(this);
    this.thread.setDaemon(true);
  }

  public HasThread(String name) {
    this.thread = new Thread(this, name);
    this.thread.setDaemon(true);
  }
  
  public Thread getThread() {
    return thread;
  }

  @Override
  public abstract void run();
  
  //// Begin delegation to Thread
  
  public final String getName() {
    return thread.getName();
  }

  public void interrupt() {
    thread.interrupt();
  }

  public final boolean isAlive() {
    return thread.isAlive();
  }

  public boolean isInterrupted() {
    return thread.isInterrupted();
  }

  public final void setDaemon(boolean on) {
    thread.setDaemon(on);
  }

  public final void setName(String name) {
    thread.setName(name);
  }

  public final void setPriority(int newPriority) {
    thread.setPriority(newPriority);
  }

  public void setUncaughtExceptionHandler(UncaughtExceptionHandler eh) {
    thread.setUncaughtExceptionHandler(eh);
  }

  public void start() {
    thread.start();
  }
  
  public final void join() throws InterruptedException {
    thread.join();
  }

  public final void join(long millis, int nanos) throws InterruptedException {
    thread.join(millis, nanos);
  }

  public final void join(long millis) throws InterruptedException {
    thread.join(millis);
  }
  //// End delegation to Thread
}