1 /* 2 * 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, software 14 * distributed under the License is distributed on an "AS IS" BASIS, 15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 16 * See the License for the specific language governing permissions and 17 * limitations under the License. 18 */ 19 package org.apache.hadoop.hbase.util; 20 21 import org.apache.hadoop.hbase.classification.InterfaceAudience; 22 23 /** 24 * Uses an incrementing algorithm instead of the default. 25 */ 26 @InterfaceAudience.Private 27 public class IncrementingEnvironmentEdge implements EnvironmentEdge { 28 29 private long timeIncrement; 30 31 /** 32 * Construct an incremental edge starting from currentTimeMillis 33 */ 34 public IncrementingEnvironmentEdge() { 35 this(System.currentTimeMillis()); 36 } 37 38 /** 39 * Construct an incremental edge with an initial amount 40 * @param initialAmount the initial value to start with 41 */ 42 public IncrementingEnvironmentEdge(long initialAmount) { 43 this.timeIncrement = initialAmount; 44 } 45 46 /** 47 * {@inheritDoc} 48 * <p> 49 * This method increments a known value for the current time each time this 50 * method is called. The first value is 1. 51 * </p> 52 */ 53 @Override 54 public synchronized long currentTime() { 55 return timeIncrement++; 56 } 57 58 /** 59 * Increment the time by the given amount 60 */ 61 public synchronized long incrementTime(long amount) { 62 timeIncrement += amount; 63 return timeIncrement; 64 } 65 }