| /* |
| * Copyright (C) 2017 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.server.audio; |
| |
| import android.util.Log; |
| |
| import java.io.PrintWriter; |
| import java.text.SimpleDateFormat; |
| import java.util.Date; |
| import java.util.LinkedList; |
| |
| public class AudioEventLogger { |
| |
| // ring buffer of events to log. |
| private final LinkedList<Event> mEvents; |
| |
| private final String mTitle; |
| |
| // the maximum number of events to keep in log |
| private final int mMemSize; |
| |
| public static abstract class Event { |
| // formatter for timestamps |
| private final static SimpleDateFormat sFormat = new SimpleDateFormat("MM-dd HH:mm:ss:SSS"); |
| |
| private final long mTimestamp; |
| |
| Event() { |
| mTimestamp = System.currentTimeMillis(); |
| } |
| |
| public String toString() { |
| return (new StringBuilder(sFormat.format(new Date(mTimestamp)))) |
| .append(" ").append(eventToString()).toString(); |
| } |
| |
| /** |
| * Causes the string message for the event to appear in the logcat. |
| * Here is an example of how to create a new event (a StringEvent), adding it to the logger |
| * (an instance of AudioEventLogger) while also making it show in the logcat: |
| * <pre> |
| * myLogger.log( |
| * (new StringEvent("something for logcat and logger")).printLog(MyClass.TAG) ); |
| * </pre> |
| * @param tag the tag for the android.util.Log.v |
| * @return the same instance of the event |
| */ |
| public Event printLog(String tag) { |
| Log.i(tag, eventToString()); |
| return this; |
| } |
| |
| /** |
| * Convert event to String. |
| * This method is only called when the logger history is about to the dumped, |
| * so this method is where expensive String conversions should be made, not when the Event |
| * subclass is created. |
| * Timestamp information will be automatically added, do not include it. |
| * @return a string representation of the event that occurred. |
| */ |
| abstract public String eventToString(); |
| } |
| |
| public static class StringEvent extends Event { |
| private final String mMsg; |
| |
| public StringEvent(String msg) { |
| mMsg = msg; |
| } |
| |
| @Override |
| public String eventToString() { |
| return mMsg; |
| } |
| } |
| |
| /** |
| * Constructor for logger. |
| * @param size the maximum number of events to keep in log |
| * @param title the string displayed before the recorded log |
| */ |
| public AudioEventLogger(int size, String title) { |
| mEvents = new LinkedList<Event>(); |
| mMemSize = size; |
| mTitle = title; |
| } |
| |
| public synchronized void log(Event evt) { |
| if (mEvents.size() >= mMemSize) { |
| mEvents.removeFirst(); |
| } |
| mEvents.add(evt); |
| } |
| |
| public synchronized void dump(PrintWriter pw) { |
| pw.println("Audio event log: " + mTitle); |
| for (Event evt : mEvents) { |
| pw.println(evt.toString()); |
| } |
| } |
| } |