001/* 002 * (C) Copyright 2017 Nuxeo SA (http://nuxeo.com/) and others. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 * 016 * Contributors: 017 * bdelbosc 018 */ 019package org.nuxeo.lib.stream.log; 020 021import static java.lang.Math.max; 022import static java.lang.Math.min; 023 024import java.util.List; 025 026/** 027 * Represent the number of messages between 2 offsets 028 * 029 * @since 9.3 030 */ 031public class LogLag { 032 protected final long lowerOffset; 033 034 protected final long upperOffset; 035 036 protected final long lag; 037 038 protected final long upper; 039 040 public LogLag(long lowerOffset, long upperOffset) { 041 this(lowerOffset, upperOffset, upperOffset - lowerOffset, upperOffset); 042 } 043 044 public LogLag(long lowerOffset, long upperOffset, long lag, long upper) { 045 this.lowerOffset = lowerOffset; 046 this.upperOffset = upperOffset; 047 this.upper = upper; 048 this.lag = lag; 049 } 050 051 public static LogLag of(long lowerOffset, long upperOffset) { 052 return new LogLag(lowerOffset, upperOffset); 053 } 054 055 public static LogLag of(long lag) { 056 return new LogLag(0, lag, lag, lag); 057 } 058 059 public static LogLag of(List<LogLag> lags) { 060 final long[] end = { 0 }; 061 final long[] pos = { Long.MAX_VALUE }; 062 final long[] lag = { 0 }; 063 final long[] endMessages = { 0 }; 064 lags.forEach(item -> { 065 if (item.lowerOffset() > 0) { 066 pos[0] = min(pos[0], item.lowerOffset()); 067 } 068 end[0] = max(end[0], item.upperOffset()); 069 endMessages[0] += item.upper(); 070 lag[0] += item.lag(); 071 }); 072 return new LogLag(pos[0] == Long.MAX_VALUE ? 0 : pos[0], end[0], lag[0], endMessages[0]); 073 } 074 075 /** 076 * Returns the number of messages between lower and upper offsets. 077 */ 078 public long lag() { 079 return lag; 080 } 081 082 /** 083 * Convert the upperOffset into a number of messages. 084 */ 085 public long upper() { 086 return upper; 087 } 088 089 /** 090 * Convert the lowerOffset into a number of messages. 091 */ 092 public long lower() { 093 return upper - lag; 094 } 095 096 public long upperOffset() { 097 return upperOffset; 098 } 099 100 public long lowerOffset() { 101 return lowerOffset; 102 } 103 104 @Override 105 public String toString() { 106 return "LogLag{" + "lower=" + lower() + ", upper=" + upper + ", lag=" + lag + ", lowerOffset=" + lowerOffset 107 + ", upperOffset=" + upperOffset + '}'; 108 } 109 110 @Override 111 public boolean equals(Object o) { 112 if (this == o) 113 return true; 114 if (o == null || getClass() != o.getClass()) 115 return false; 116 117 LogLag lag1 = (LogLag) o; 118 119 return lag == lag1.lag; 120 } 121 122 @Override 123 public int hashCode() { 124 return (int) (lag ^ (lag >>> 32)); 125 } 126 127}