samza-core/src/main/scala/org/apache/samza/coordinator/Latch.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.samza.coordinator;

import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;


/**
 * latch implementation for the coordination service.
 * Supports different size latches.
 * await() returns when either latch reaches N (N participants call countDown()) or timeout.
 */
public interface Latch {
  void await(long timeout, TimeUnit tu) throws TimeoutException;
  void countDown();
}