io.trino.execution.executor.scheduler.Gate Maven / Gradle / Ivy
/*
* Licensed 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 io.trino.execution.executor.scheduler;
import com.google.errorprone.annotations.ThreadSafe;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
@ThreadSafe
final class Gate
{
private final Lock lock = new ReentrantLock();
private final Condition opened = lock.newCondition();
private boolean open;
public Gate(boolean opened)
{
this.open = opened;
}
public void close()
{
lock.lock();
try {
open = false;
}
finally {
lock.unlock();
}
}
public void open()
{
lock.lock();
try {
open = true;
opened.signalAll();
}
finally {
lock.unlock();
}
}
public void awaitOpen()
throws InterruptedException
{
lock.lock();
try {
while (!open) {
opened.await();
}
}
finally {
lock.unlock();
}
}
}