001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018 019 package org.apache.hadoop.yarn.event; 020 021 import org.apache.hadoop.classification.InterfaceAudience.Public; 022 import org.apache.hadoop.classification.InterfaceStability.Evolving; 023 024 /** 025 * Parent class of all the events. All events extend this class. 026 */ 027 @Public 028 @Evolving 029 public abstract class AbstractEvent<TYPE extends Enum<TYPE>> 030 implements Event<TYPE> { 031 032 private final TYPE type; 033 private final long timestamp; 034 035 // use this if you DON'T care about the timestamp 036 public AbstractEvent(TYPE type) { 037 this.type = type; 038 // We're not generating a real timestamp here. It's too expensive. 039 timestamp = -1L; 040 } 041 042 // use this if you care about the timestamp 043 public AbstractEvent(TYPE type, long timestamp) { 044 this.type = type; 045 this.timestamp = timestamp; 046 } 047 048 @Override 049 public long getTimestamp() { 050 return timestamp; 051 } 052 053 @Override 054 public TYPE getType() { 055 return type; 056 } 057 058 @Override 059 public String toString() { 060 return "EventType: " + getType(); 061 } 062 }