1 /* 2 * Copyright (C) 2008 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.util; 17 18 import static android.os.Process.THREAD_PRIORITY_BACKGROUND; 19 import static android.os.Process.THREAD_PRIORITY_FOREGROUND; 20 21 import android.os.Looper; 22 import android.os.Process; 23 24 import java.util.Map; 25 import java.util.concurrent.ConcurrentHashMap; 26 import java.util.concurrent.ExecutorService; 27 import java.util.concurrent.LinkedBlockingQueue; 28 import java.util.concurrent.ThreadFactory; 29 import java.util.concurrent.ThreadPoolExecutor; 30 import java.util.concurrent.TimeUnit; 31 import java.util.concurrent.atomic.AtomicInteger; 32 33 /** 34 * Various different executors used in Launcher 35 */ 36 public class Executors { 37 38 private static final int POOL_SIZE = 39 Math.max(Runtime.getRuntime().availableProcessors(), 2); 40 private static final int KEEP_ALIVE = 1; 41 42 /** Dedicated executor instances for work depending on other packages. */ 43 private static final Map<String, LooperExecutor> PACKAGE_EXECUTORS = new ConcurrentHashMap<>(); 44 45 /** 46 * An {@link ThreadPoolExecutor} to be used with async task with no limit on the queue size. 47 */ 48 public static final ThreadPoolExecutor THREAD_POOL_EXECUTOR = new ThreadPoolExecutor( 49 POOL_SIZE, POOL_SIZE, KEEP_ALIVE, TimeUnit.SECONDS, new LinkedBlockingQueue<>()); 50 51 /** 52 * An {@link LooperExecutor} to be used with async task where order is important. 53 */ 54 public static final LooperExecutor ORDERED_BG_EXECUTOR = 55 new LooperExecutor("BackgroundExecutor", THREAD_PRIORITY_BACKGROUND); 56 57 /** 58 * Returns the executor for running tasks on the main thread. 59 */ 60 public static final LooperExecutor MAIN_EXECUTOR = 61 new LooperExecutor(Looper.getMainLooper(), THREAD_PRIORITY_FOREGROUND); 62 63 /** 64 * A background executor for using time sensitive actions where user is waiting for response. 65 */ 66 public static final LooperExecutor UI_HELPER_EXECUTOR = 67 new LooperExecutor("UiThreadHelper", Process.THREAD_PRIORITY_FOREGROUND); 68 69 70 /** A background executor to preinflate views. */ 71 public static final ExecutorService VIEW_PREINFLATION_EXECUTOR = 72 java.util.concurrent.Executors.newSingleThreadExecutor( 73 new SimpleThreadFactory( 74 "preinflate-allapps-icons", THREAD_PRIORITY_BACKGROUND)); 75 76 /** 77 * Executor used for running Launcher model related tasks (eg loading icons or updated db) 78 */ 79 public static final LooperExecutor MODEL_EXECUTOR = new LooperExecutor("launcher-loader"); 80 81 /** 82 * Returns and caches a single thread executor for a given package. 83 * 84 * @param packageName Package associated with the executor. 85 */ getPackageExecutor(String packageName)86 public static LooperExecutor getPackageExecutor(String packageName) { 87 return PACKAGE_EXECUTORS.computeIfAbsent(packageName, LooperExecutor::new); 88 } 89 90 /** 91 * A simple ThreadFactory to set the thread name and priority when used with executors. 92 */ 93 public static class SimpleThreadFactory implements ThreadFactory { 94 95 private final int mPriority; 96 private final String mNamePrefix; 97 98 private final AtomicInteger mCount = new AtomicInteger(0); 99 SimpleThreadFactory(String namePrefix, int priority)100 public SimpleThreadFactory(String namePrefix, int priority) { 101 mNamePrefix = namePrefix; 102 mPriority = priority; 103 } 104 105 @Override newThread(Runnable runnable)106 public Thread newThread(Runnable runnable) { 107 Thread t = new Thread(() -> { 108 Process.setThreadPriority(mPriority); 109 runnable.run(); 110 }, mNamePrefix + mCount.incrementAndGet()); 111 return t; 112 } 113 } 114 } 115