BluetoothServerSocket.java revision 6d8b80dd8c56dba02dcb6e64ace37fb85aeee1f5
1/* 2 * Copyright (C) 2009 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 android.bluetooth; 18 19import android.os.Handler; 20 21import java.io.Closeable; 22import java.io.IOException; 23 24/** 25 * A listening Bluetooth socket. 26 * 27 * <p>The interface for Bluetooth Sockets is similar to that of TCP sockets: 28 * {@link java.net.Socket} and {@link java.net.ServerSocket}. On the server 29 * side, use a {@link BluetoothServerSocket} to create a listening server 30 * socket. When a connection is accepted by the {@link BluetoothServerSocket}, 31 * it will return a new {@link BluetoothSocket} to manage the connection. 32 * On the client side, use a single {@link BluetoothSocket} to both initiate 33 * an outgoing connection and to manage the connection. 34 * 35 * <p>The most common type of Bluetooth socket is RFCOMM, which is the type 36 * supported by the Android APIs. RFCOMM is a connection-oriented, streaming 37 * transport over Bluetooth. It is also known as the Serial Port Profile (SPP). 38 * 39 * <p>To create a listening {@link BluetoothServerSocket} that's ready for 40 * incoming connections, use 41 * {@link BluetoothAdapter#listenUsingRfcommWithServiceRecord 42 * BluetoothAdapter.listenUsingRfcommWithServiceRecord()}. Then call 43 * {@link #accept()} to listen for incoming connection requests. This call 44 * will block until a connection is established, at which point, it will return 45 * a {@link BluetoothSocket} to manage the connection. Once the {@link 46 * BluetoothSocket} is acquired, it's a good idea to call {@link #close()} on 47 * the {@link BluetoothServerSocket} when it's no longer needed for accepting 48 * connections. Closing the {@link BluetoothServerSocket} will <em>not</em> 49 * close the returned {@link BluetoothSocket}. 50 * 51 * <p>{@link BluetoothServerSocket} is thread 52 * safe. In particular, {@link #close} will always immediately abort ongoing 53 * operations and close the server socket. 54 * 55 * <p class="note"><strong>Note:</strong> 56 * Requires the {@link android.Manifest.permission#BLUETOOTH} permission. 57 * 58 * {@see BluetoothSocket} 59 */ 60public final class BluetoothServerSocket implements Closeable { 61 62 /*package*/ final BluetoothSocket mSocket; 63 private Handler mHandler; 64 private int mMessage; 65 private final int mChannel; 66 67 /** 68 * Construct a socket for incoming connections. 69 * @param type type of socket 70 * @param auth require the remote device to be authenticated 71 * @param encrypt require the connection to be encrypted 72 * @param port remote port 73 * @throws IOException On error, for example Bluetooth not available, or 74 * insufficient privileges 75 */ 76 /*package*/ BluetoothServerSocket(int type, boolean auth, boolean encrypt, int port) 77 throws IOException { 78 mChannel = port; 79 mSocket = new BluetoothSocket(type, -1, auth, encrypt, null, port, null); 80 } 81 82 /** 83 * Block until a connection is established. 84 * <p>Returns a connected {@link BluetoothSocket} on successful connection. 85 * <p>Once this call returns, it can be called again to accept subsequent 86 * incoming connections. 87 * <p>{@link #close} can be used to abort this call from another thread. 88 * @return a connected {@link BluetoothSocket} 89 * @throws IOException on error, for example this call was aborted, or 90 * timeout 91 */ 92 public BluetoothSocket accept() throws IOException { 93 return accept(-1); 94 } 95 96 /** 97 * Block until a connection is established, with timeout. 98 * <p>Returns a connected {@link BluetoothSocket} on successful connection. 99 * <p>Once this call returns, it can be called again to accept subsequent 100 * incoming connections. 101 * <p>{@link #close} can be used to abort this call from another thread. 102 * @return a connected {@link BluetoothSocket} 103 * @throws IOException on error, for example this call was aborted, or 104 * timeout 105 */ 106 public BluetoothSocket accept(int timeout) throws IOException { 107 return mSocket.accept(timeout); 108 } 109 110 /** 111 * Immediately close this socket, and release all associated resources. 112 * <p>Causes blocked calls on this socket in other threads to immediately 113 * throw an IOException. 114 * <p>Closing the {@link BluetoothServerSocket} will <em>not</em> 115 * close any {@link BluetoothSocket} received from {@link #accept()}. 116 */ 117 public void close() throws IOException { 118 synchronized (this) { 119 if (mHandler != null) { 120 mHandler.obtainMessage(mMessage).sendToTarget(); 121 } 122 } 123 mSocket.close(); 124 } 125 126 /*package*/ synchronized void setCloseHandler(Handler handler, int message) { 127 mHandler = handler; 128 mMessage = message; 129 } 130 131 /** 132 * Returns the channel on which this socket is bound. 133 * @hide 134 */ 135 public int getChannel() { 136 return mChannel; 137 } 138} 139