1 /* 2 * Copyright (C) 2014 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 17 package com.android.server.telecom.testapps; 18 19 import android.os.ConditionVariable; 20 import android.os.Handler; 21 import android.os.Looper; 22 import android.util.Log; 23 24 import java.lang.AutoCloseable; 25 import java.lang.Exception; 26 import java.lang.Override; 27 import java.lang.String; 28 import java.lang.Thread; 29 import java.lang.Throwable; 30 import java.util.concurrent.TimeoutException; 31 32 /** 33 * Camera thread class used for handling camera callbacks. 34 */ 35 public class CameraThread implements AutoCloseable { 36 private static final String TAG = "CameraThread"; 37 private static final boolean VERBOSE = Log.isLoggable(TAG, Log.VERBOSE); 38 39 // Timeout for initializing looper and opening camera in Milliseconds. 40 private static final long WAIT_FOR_COMMAND_TO_COMPLETE = 5000; 41 private Looper mLooper = null; 42 private Handler mHandler = null; 43 44 /** 45 * Create and start a looper thread, return the Handler 46 */ start()47 public synchronized Handler start() throws Exception { 48 final ConditionVariable startDone = new ConditionVariable(); 49 if (mHandler != null) { 50 Log.w(TAG, "Looper thread already started"); 51 return mHandler; 52 } 53 54 new Thread() { 55 @Override 56 public void run() { 57 if (VERBOSE) Log.v(TAG, "start loopRun"); 58 Looper.prepare(); 59 // Save the looper so that we can terminate this thread 60 // after we are done with it. 61 mLooper = Looper.myLooper(); 62 mHandler = new Handler(); 63 startDone.open(); 64 Looper.loop(); 65 if (VERBOSE) Log.v(TAG, "createLooperThread: finished"); 66 } 67 }.start(); 68 69 if (VERBOSE) Log.v(TAG, "start waiting for looper"); 70 if (!startDone.block(WAIT_FOR_COMMAND_TO_COMPLETE)) { 71 throw new TimeoutException("createLooperThread: start timeout"); 72 } 73 return mHandler; 74 } 75 76 /** 77 * Terminate the looper thread 78 */ close()79 public synchronized void close() throws Exception { 80 if (mLooper == null || mHandler == null) { 81 Log.w(TAG, "Looper thread doesn't start yet"); 82 return; 83 } 84 85 if (VERBOSE) Log.v(TAG, "Terminate looper thread"); 86 mLooper.quit(); 87 mLooper.getThread().join(); 88 mLooper = null; 89 mHandler = null; 90 } 91 92 @Override finalize()93 protected void finalize() throws Throwable { 94 try { 95 close(); 96 } finally { 97 super.finalize(); 98 } 99 } 100 } 101