io.netty.util.concurrent.FastThreadLocalThread Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* Copyright 2014 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.util.concurrent;
import io.netty.util.internal.InternalThreadLocalMap;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
/**
* A special {@link Thread} that provides fast access to {@link FastThreadLocal} variables.
*/
public class FastThreadLocalThread extends Thread {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(FastThreadLocalThread.class);
// This will be set to true if we have a chance to wrap the Runnable.
private final boolean cleanupFastThreadLocals;
private InternalThreadLocalMap threadLocalMap;
public FastThreadLocalThread() {
cleanupFastThreadLocals = false;
}
public FastThreadLocalThread(Runnable target) {
super(FastThreadLocalRunnable.wrap(target));
cleanupFastThreadLocals = true;
}
public FastThreadLocalThread(ThreadGroup group, Runnable target) {
super(group, FastThreadLocalRunnable.wrap(target));
cleanupFastThreadLocals = true;
}
public FastThreadLocalThread(String name) {
super(name);
cleanupFastThreadLocals = false;
}
public FastThreadLocalThread(ThreadGroup group, String name) {
super(group, name);
cleanupFastThreadLocals = false;
}
public FastThreadLocalThread(Runnable target, String name) {
super(FastThreadLocalRunnable.wrap(target), name);
cleanupFastThreadLocals = true;
}
public FastThreadLocalThread(ThreadGroup group, Runnable target, String name) {
super(group, FastThreadLocalRunnable.wrap(target), name);
cleanupFastThreadLocals = true;
}
public FastThreadLocalThread(ThreadGroup group, Runnable target, String name, long stackSize) {
super(group, FastThreadLocalRunnable.wrap(target), name, stackSize);
cleanupFastThreadLocals = true;
}
/**
* Returns the internal data structure that keeps the thread-local variables bound to this thread.
* Note that this method is for internal use only, and thus is subject to change at any time.
*/
public final InternalThreadLocalMap threadLocalMap() {
if (this != Thread.currentThread() && logger.isWarnEnabled()) {
logger.warn(new RuntimeException("It's not thread-safe to get 'threadLocalMap' " +
"which doesn't belong to the caller thread"));
}
return threadLocalMap;
}
/**
* Sets the internal data structure that keeps the thread-local variables bound to this thread.
* Note that this method is for internal use only, and thus is subject to change at any time.
*/
public final void setThreadLocalMap(InternalThreadLocalMap threadLocalMap) {
if (this != Thread.currentThread() && logger.isWarnEnabled()) {
logger.warn(new RuntimeException("It's not thread-safe to set 'threadLocalMap' " +
"which doesn't belong to the caller thread"));
}
this.threadLocalMap = threadLocalMap;
}
/**
* Returns {@code true} if {@link FastThreadLocal#removeAll()} will be called once {@link #run()} completes.
*/
public boolean willCleanupFastThreadLocals() {
return cleanupFastThreadLocals;
}
/**
* Returns {@code true} if {@link FastThreadLocal#removeAll()} will be called once {@link Thread#run()} completes.
*/
public static boolean willCleanupFastThreadLocals(Thread thread) {
return thread instanceof FastThreadLocalThread &&
((FastThreadLocalThread) thread).willCleanupFastThreadLocals();
}
/**
* Query whether this thread is allowed to perform blocking calls or not.
* {@link FastThreadLocalThread}s are often used in event-loops, where blocking calls are forbidden in order to
* prevent event-loop stalls, so this method returns {@code false} by default.
*
* Subclasses of {@link FastThreadLocalThread} can override this method if they are not meant to be used for
* running event-loops.
*
* @return {@code false}, unless overriden by a subclass.
*/
public boolean permitBlockingCalls() {
return false;
}
}