| /* |
| * 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.ignite; |
| |
| import java.io.Closeable; |
| import java.util.concurrent.TimeUnit; |
| |
| /** |
| * This interface provides a rich API for working with distributed count down latch. |
| * <p> |
| * <h1 class="header">Functionality</h1> |
| * Distributed count down latch provides functionality similar to {@code java.util.CountDownLatch}. |
| * Note that you cannot remove count down latch having count greater that zero. It should be |
| * counted down to zero first. |
| * <h1 class="header">Creating Distributed Count Down Latch</h1> |
| * Instance of cache count down latch can be created by calling the following method: |
| * {@link Ignite#countDownLatch(String, int, boolean, boolean)}. |
| */ |
| public interface IgniteCountDownLatch extends Closeable { |
| /** |
| * Gets name of the latch. |
| * |
| * @return Name of the latch. |
| */ |
| public String name(); |
| |
| /** |
| * Gets current count value of the latch. |
| * |
| * @return Current count. |
| */ |
| public int count(); |
| |
| /** |
| * Gets initial count value of the latch. |
| * |
| * @return Initial count. |
| */ |
| public int initialCount(); |
| |
| /** |
| * Gets {@code autoDelete} flag. If this flag is {@code true} latch is removed |
| * from cache when it has been counted down to 0. |
| * |
| * @return Value of {@code autoDelete} flag. |
| */ |
| public boolean autoDelete(); |
| |
| /** |
| * Causes the current thread to wait until the latch has counted down to |
| * zero, unless current thread is interrupted. |
| * <p> |
| * If the current count of the latch is zero then this method returns immediately. |
| * <p> |
| * If the current count is greater than zero then the current |
| * thread becomes disabled for thread scheduling purposes and lies |
| * dormant until one of two things happen: |
| * <ul> |
| * <li>The count reaches zero due to invocations of the |
| * {@link #countDown} method on any node; or |
| * <li>Some other thread interrupts the current thread. |
| * </ul> |
| * <p> |
| * If the current thread: |
| * <ul> |
| * <li>has its interrupted status set on entry to this method; or |
| * <li>is interrupted while waiting, |
| * </ul> |
| * then {@link org.apache.ignite.internal.IgniteInterruptedCheckedException} is thrown and the current thread's |
| * interrupted status is cleared. |
| * |
| * @throws IgniteException If operation failed. |
| * @throws org.apache.ignite.IgniteInterruptedException if the current thread is interrupted |
| * while waiting |
| */ |
| public void await() throws IgniteException; |
| |
| /** |
| * Causes the current thread to wait until the latch has counted down to |
| * zero, unless the thread is interrupted, or the specified waiting time elapses. |
| * <p> |
| * If the current count is zero then this method returns immediately |
| * with the value {@code true}. |
| * <p> |
| * If the current count is greater than zero then the current |
| * thread becomes disabled for thread scheduling purposes and lies |
| * dormant until one of three things happen: |
| * <ul> |
| * <li>The count reaches zero due to invocations of the |
| * {@link #countDown} method on any node; or |
| * <li>Some other thread interrupts the current thread; or |
| * <li>The specified waiting time elapses. |
| * </ul> |
| * <p> |
| * If the count reaches zero then the method returns with the |
| * value {@code true}. |
| * <p> |
| * If the current thread: |
| * <ul> |
| * <li>has its interrupted status set on entry to this method; or |
| * <li>is interrupted while waiting, |
| * </ul> |
| * then {@link org.apache.ignite.internal.IgniteInterruptedCheckedException} is thrown and the current thread's |
| * interrupted status is cleared. |
| * <p> |
| * If the specified waiting time elapses then the value {@code false} |
| * is returned. If the time is less than or equal to zero, the method |
| * will not wait at all. |
| * |
| * @param timeout The maximum time to wait in milliseconds. |
| * @return {@code True} if the count reached zero and {@code false} |
| * if the waiting time elapsed before the count reached zero. |
| * @throws org.apache.ignite.IgniteInterruptedException If the current thread is interrupted |
| * while waiting. |
| * @throws IgniteException If operation failed. |
| */ |
| public boolean await(long timeout) throws IgniteException; |
| |
| /** |
| * Causes the current thread to wait until the latch has counted down to |
| * zero, unless the thread is interrupted, or the specified waiting time elapses. |
| * <p> |
| * If the current count is zero then this method returns immediately |
| * with the value {@code true}. |
| * <p> |
| * If the current count is greater than zero then the current |
| * thread becomes disabled for thread scheduling purposes and lies |
| * dormant until one of three things happen: |
| * <ul> |
| * <li>The count reaches zero due to invocations of the |
| * {@link #countDown} method on any node; or |
| * <li>Some other thread interrupts the current thread; or |
| * <li>The specified waiting time elapses. |
| * </ul> |
| * <p> |
| * If the count reaches zero then the method returns with the |
| * value {@code true}. |
| * <p> |
| * If the current thread: |
| * <ul> |
| * <li>has its interrupted status set on entry to this method; or |
| * <li>is interrupted while waiting, |
| * </ul> |
| * then {@link org.apache.ignite.internal.IgniteInterruptedCheckedException} is thrown and the current thread's |
| * interrupted status is cleared. |
| * <p> |
| * If the specified waiting time elapses then the value {@code false} |
| * is returned. If the time is less than or equal to zero, the method |
| * will not wait at all. |
| * |
| * |
| * @param timeout The maximum time to wait. |
| * @param unit The time unit of the {@code timeout} argument. |
| * @return {@code True} if the count reached zero and {@code false} |
| * if the waiting time elapsed before the count reached zero. |
| * @throws org.apache.ignite.IgniteInterruptedException If the current thread is interrupted |
| * while waiting. |
| * @throws IgniteException If operation failed. |
| */ |
| public boolean await(long timeout, TimeUnit unit) throws IgniteException; |
| |
| /** |
| * Decrements the count of the latch, releasing all waiting threads |
| * on all nodes if the count reaches zero. |
| * <p> |
| * If the current count is greater than zero then it is decremented. |
| * If the new count is zero then all waiting threads are re-enabled for |
| * thread scheduling purposes. |
| * <p> |
| * If the current count equals zero then nothing happens. |
| * |
| * @return Count after decrement. |
| * @throws IgniteException If operation failed. |
| */ |
| public int countDown() throws IgniteException; |
| |
| /** |
| * Decreases the count of the latch using passed in value, |
| * releasing all waiting threads on all nodes if the count reaches zero. |
| * <p> |
| * If the current count is greater than zero then it is decreased. |
| * If the new count is zero then all waiting threads are re-enabled for |
| * thread scheduling purposes. |
| * <p> |
| * If the current count equals zero then nothing happens. |
| * |
| * @param val Value to decrease counter on. |
| * @return Count after decreasing. |
| * @throws IgniteException If operation failed. |
| */ |
| public int countDown(int val) throws IgniteException; |
| |
| /** |
| * Counts down this latch to zero, releasing all waiting threads on all nodes. |
| * <p> |
| * If the current count equals zero then nothing happens. |
| * |
| * @throws IgniteException If operation failed. |
| */ |
| public void countDownAll() throws IgniteException; |
| |
| /** |
| * Gets {@code removed} status of the latch. |
| * |
| * @return {@code True} if latch was removed from cache, {@code false} otherwise. |
| */ |
| public boolean removed(); |
| |
| /** |
| * Removes this count down latch. |
| * |
| * @throws IgniteException If operation failed. |
| */ |
| @Override public void close(); |
| } |
