1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 package org.apache.giraph.zk; 20 21 /** 22 * Synchronize on waiting for an event to have happened. This is a one-time 23 * event. 24 */ 25 public interface BspEvent { 26 /** 27 * Reset the permanent signal. 28 */ 29 void reset(); 30 31 /** 32 * The event occurred and the occurrence has been logged for future 33 * waiters. 34 */ 35 void signal(); 36 37 /** 38 * Wait until the event occurred or waiting timed out. 39 * @param msecs Milliseconds to wait until the event occurred. 0 indicates 40 * check immediately. -1 indicates wait forever. 41 * @return true if event occurred, false if timed out while waiting 42 */ 43 boolean waitMsecs(int msecs); 44 45 /** 46 * Waits until timeout or fails with runtime exception. 47 * @param timeout Throws exception if waiting takes longer than timeout. 48 */ 49 void waitForTimeoutOrFail(long timeout); 50 }