1/* 2 * Copyright (C) 2013 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 17package com.android.internal.os; 18 19import android.os.Handler; 20import android.os.HandlerThread; 21 22/** 23 * Shared singleton background thread for each process. 24 */ 25public final class BackgroundThread extends HandlerThread { 26 private static BackgroundThread sInstance; 27 private static Handler sHandler; 28 29 private BackgroundThread() { 30 super("android.bg", android.os.Process.THREAD_PRIORITY_BACKGROUND); 31 } 32 33 private static void ensureThreadLocked() { 34 if (sInstance == null) { 35 sInstance = new BackgroundThread(); 36 sInstance.start(); 37 sHandler = new Handler(sInstance.getLooper()); 38 } 39 } 40 41 public static BackgroundThread get() { 42 synchronized (BackgroundThread.class) { 43 ensureThreadLocked(); 44 return sInstance; 45 } 46 } 47 48 public static Handler getHandler() { 49 synchronized (BackgroundThread.class) { 50 ensureThreadLocked(); 51 return sHandler; 52 } 53 } 54} 55