1 /* 2 * Copyright (C) 2012 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.internal.os; 18 19 /** 20 * Helper class for passing more arguments though a message 21 * and avoiding allocation of a custom class for wrapping the 22 * arguments. This class maintains a pool of instances and 23 * it is responsibility of the client to recycle and instance 24 * once it is no longer used. 25 */ 26 public final class SomeArgs { 27 28 private static final int MAX_POOL_SIZE = 10; 29 30 private static SomeArgs sPool; 31 private static int sPoolSize; 32 private static Object sPoolLock = new Object(); 33 34 private SomeArgs mNext; 35 36 private boolean mInPool; 37 38 static final int WAIT_NONE = 0; 39 static final int WAIT_WAITING = 1; 40 static final int WAIT_FINISHED = 2; 41 int mWaitState = WAIT_NONE; 42 43 public Object arg1; 44 public Object arg2; 45 public Object arg3; 46 public Object arg4; 47 public Object arg5; 48 public Object arg6; 49 public int argi1; 50 public int argi2; 51 public int argi3; 52 public int argi4; 53 public int argi5; 54 public int argi6; 55 SomeArgs()56 private SomeArgs() { 57 /* do nothing - reduce visibility */ 58 } 59 obtain()60 public static SomeArgs obtain() { 61 synchronized (sPoolLock) { 62 if (sPoolSize > 0) { 63 SomeArgs args = sPool; 64 sPool = sPool.mNext; 65 args.mNext = null; 66 args.mInPool = false; 67 sPoolSize--; 68 return args; 69 } else { 70 return new SomeArgs(); 71 } 72 } 73 } 74 recycle()75 public void recycle() { 76 if (mInPool) { 77 throw new IllegalStateException("Already recycled."); 78 } 79 if (mWaitState != WAIT_NONE) { 80 return; 81 } 82 synchronized (sPoolLock) { 83 clear(); 84 if (sPoolSize < MAX_POOL_SIZE) { 85 mNext = sPool; 86 mInPool = true; 87 sPool = this; 88 sPoolSize++; 89 } 90 } 91 } 92 clear()93 private void clear() { 94 arg1 = null; 95 arg2 = null; 96 arg3 = null; 97 arg4 = null; 98 arg5 = null; 99 arg6 = null; 100 argi1 = 0; 101 argi2 = 0; 102 argi3 = 0; 103 argi4 = 0; 104 argi5 = 0; 105 argi6 = 0; 106 } 107 } 108