1 /* 2 * Copyright (C) 2019 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.android.launcher3.logging; 17 18 19 import android.util.Log; 20 import java.io.PrintWriter; 21 import java.text.SimpleDateFormat; 22 import java.util.Arrays; 23 import java.util.Date; 24 import java.util.Locale; 25 import java.util.Random; 26 27 /** 28 * A utility class to record and log events. Events are stored in a fixed size array and old logs 29 * are purged as new events come. 30 */ 31 public class EventLogArray { 32 33 private static final int TYPE_ONE_OFF = 0; 34 private static final int TYPE_FLOAT = 1; 35 private static final int TYPE_INTEGER = 2; 36 private static final int TYPE_BOOL_TRUE = 3; 37 private static final int TYPE_BOOL_FALSE = 4; 38 39 private final String name; 40 private final EventEntry[] logs; 41 private int nextIndex; 42 private int mLogId; 43 EventLogArray(String name, int size)44 public EventLogArray(String name, int size) { 45 this.name = name; 46 logs = new EventEntry[size]; 47 nextIndex = 0; 48 } 49 addLog(String event)50 public void addLog(String event) { 51 addLog(TYPE_ONE_OFF, event, 0); 52 } 53 addLog(String event, int extras)54 public void addLog(String event, int extras) { 55 addLog(TYPE_INTEGER, event, extras); 56 } 57 addLog(String event, boolean extras)58 public void addLog(String event, boolean extras) { 59 addLog(extras ? TYPE_BOOL_TRUE : TYPE_BOOL_FALSE, event, 0); 60 } 61 addLog(int type, String event, float extras)62 private void addLog(int type, String event, float extras) { 63 // Merge the logs if its a duplicate 64 int last = (nextIndex + logs.length - 1) % logs.length; 65 int secondLast = (nextIndex + logs.length - 2) % logs.length; 66 if (isEntrySame(logs[last], type, event) && isEntrySame(logs[secondLast], type, event)) { 67 logs[last].update(type, event, extras, mLogId); 68 logs[secondLast].duplicateCount++; 69 return; 70 } 71 72 if (logs[nextIndex] == null) { 73 logs[nextIndex] = new EventEntry(); 74 } 75 logs[nextIndex].update(type, event, extras, mLogId); 76 nextIndex = (nextIndex + 1) % logs.length; 77 } 78 clear()79 public void clear() { 80 Arrays.setAll(logs, (i) -> null); 81 } 82 dump(String prefix, PrintWriter writer)83 public void dump(String prefix, PrintWriter writer) { 84 writer.println(prefix + "EventLog (" + name + ") history:"); 85 SimpleDateFormat sdf = new SimpleDateFormat(" HH:mm:ss.SSSZ ", Locale.US); 86 Date date = new Date(); 87 88 for (int i = 0; i < logs.length; i++) { 89 EventEntry log = logs[(nextIndex + logs.length - i - 1) % logs.length]; 90 if (log == null) { 91 continue; 92 } 93 date.setTime(log.time); 94 95 StringBuilder msg = new StringBuilder(prefix).append(sdf.format(date)) 96 .append(log.event); 97 switch (log.type) { 98 case TYPE_BOOL_FALSE: 99 msg.append(": false"); 100 break; 101 case TYPE_BOOL_TRUE: 102 msg.append(": true"); 103 break; 104 case TYPE_FLOAT: 105 msg.append(": ").append(log.extras); 106 break; 107 case TYPE_INTEGER: 108 msg.append(": ").append((int) log.extras); 109 break; 110 default: // fall out 111 } 112 if (log.duplicateCount > 0) { 113 msg.append(" & ").append(log.duplicateCount).append(" similar events"); 114 } 115 msg.append(" traceId: ").append(log.traceId); 116 writer.println(msg); 117 } 118 } 119 120 /** Returns a 3 digit random number between 100-999 */ generateAndSetLogId()121 public int generateAndSetLogId() { 122 Random r = new Random(); 123 mLogId = r.nextInt(900) + 100; 124 return mLogId; 125 } 126 isEntrySame(EventEntry entry, int type, String event)127 private boolean isEntrySame(EventEntry entry, int type, String event) { 128 return entry != null && entry.type == type && entry.event.equals(event); 129 } 130 131 /** A single event entry. */ 132 private static class EventEntry { 133 134 private int type; 135 private String event; 136 private float extras; 137 private long time; 138 private int duplicateCount; 139 private int traceId; 140 update(int type, String event, float extras, int traceId)141 public void update(int type, String event, float extras, int traceId) { 142 this.type = type; 143 this.event = event; 144 this.extras = extras; 145 this.traceId = traceId; 146 time = System.currentTimeMillis(); 147 duplicateCount = 0; 148 } 149 } 150 } 151