19066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project/* 29066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Copyright (C) 2006 The Android Open Source Project 39066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 49066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Licensed under the Apache License, Version 2.0 (the "License"); 59066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * you may not use this file except in compliance with the License. 69066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * You may obtain a copy of the License at 79066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 89066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * http://www.apache.org/licenses/LICENSE-2.0 99066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 109066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Unless required by applicable law or agreed to in writing, software 119066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * distributed under the License is distributed on an "AS IS" BASIS, 129066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 139066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * See the License for the specific language governing permissions and 149066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * limitations under the License. 159066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 169066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 179066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectpackage android.os; 189066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 199066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project/** 209066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Reference to a Handler, which others can use to send messages to it. 219066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * This allows for the implementation of message-based communication across 229066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * processes, by creating a Messenger pointing to a Handler in one process, 239066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * and handing that Messenger to another process. 249066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 259066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectpublic final class Messenger implements Parcelable { 269066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project private final IMessenger mTarget; 279066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 289066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 299066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Create a new Messenger pointing to the given Handler. Any Message 309066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * objects sent through this Messenger will appear in the Handler as if 319066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * {@link Handler#sendMessage(Message) Handler.sendMessage(Message)} had 328ea138cbf12b140d43fd81f4f12fe1a9234f1f25Dianne Hackborn * been called directly. 339066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 349066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * @param target The Handler that will receive sent messages. 359066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 369066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public Messenger(Handler target) { 379066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project mTarget = target.getIMessenger(); 389066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 399066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 409066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 419066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Send a Message to this Messenger's Handler. 429066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 439066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * @param message The Message to send. Usually retrieved through 449066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * {@link Message#obtain() Message.obtain()}. 459066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 469066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * @throws RemoteException Throws DeadObjectException if the target 479066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Handler no longer exists. 489066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 499066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public void send(Message message) throws RemoteException { 509066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project mTarget.send(message); 519066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 529066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 539066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 549066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Retrieve the IBinder that this Messenger is using to communicate with 559066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * its associated Handler. 569066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 579066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * @return Returns the IBinder backing this Messenger. 589066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 599066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public IBinder getBinder() { 609066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return mTarget.asBinder(); 619066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 629066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 639066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 649066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Comparison operator on two Messenger objects, such that true 659066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * is returned then they both point to the same Handler. 669066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 679066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public boolean equals(Object otherObj) { 689066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (otherObj == null) { 699066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return false; 709066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 719066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project try { 729066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return mTarget.asBinder().equals(((Messenger)otherObj) 739066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project .mTarget.asBinder()); 749066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } catch (ClassCastException e) { 759066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 769066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return false; 779066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 789066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 799066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public int hashCode() { 809066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return mTarget.asBinder().hashCode(); 819066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 829066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 839066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public int describeContents() { 849066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return 0; 859066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 869066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 879066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public void writeToParcel(Parcel out, int flags) { 889066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project out.writeStrongBinder(mTarget.asBinder()); 899066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 909066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 919066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public static final Parcelable.Creator<Messenger> CREATOR 929066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project = new Parcelable.Creator<Messenger>() { 939066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public Messenger createFromParcel(Parcel in) { 949066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project IBinder target = in.readStrongBinder(); 959066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return target != null ? new Messenger(target) : null; 969066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 979066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 989066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public Messenger[] newArray(int size) { 999066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return new Messenger[size]; 1009066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1019066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project }; 1029066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1039066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 1049066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Convenience function for writing either a Messenger or null pointer to 1059066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * a Parcel. You must use this with {@link #readMessengerOrNullFromParcel} 1069066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * for later reading it. 1079066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 1089066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * @param messenger The Messenger to write, or null. 1099066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * @param out Where to write the Messenger. 1109066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 1119066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public static void writeMessengerOrNullToParcel(Messenger messenger, 1129066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project Parcel out) { 1139066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project out.writeStrongBinder(messenger != null ? messenger.mTarget.asBinder() 1149066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project : null); 1159066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1169066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1179066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 1189066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Convenience function for reading either a Messenger or null pointer from 1199066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * a Parcel. You must have previously written the Messenger with 1209066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * {@link #writeMessengerOrNullToParcel}. 1219066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 1229066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * @param in The Parcel containing the written Messenger. 1239066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 1249066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * @return Returns the Messenger read from the Parcel, or null if null had 1259066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * been written. 1269066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 1279066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public static Messenger readMessengerOrNullFromParcel(Parcel in) { 1289066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project IBinder b = in.readStrongBinder(); 1299066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return b != null ? new Messenger(b) : null; 1309066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1319066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1329066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 1339066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Create a Messenger from a raw IBinder, which had previously been 1349066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * retrieved with {@link #getBinder}. 1359066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 1369066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * @param target The IBinder this Messenger should communicate with. 1379066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 1389066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public Messenger(IBinder target) { 1399066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project mTarget = IMessenger.Stub.asInterface(target); 1409066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1419066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project} 142