Android example source code file (ScoSocket.java)

This example Android source code file (ScoSocket.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

android, bad, dbg, handler, no, object, os, scosocket, state_accept, state_closed, state_connected, state_connecting, state_ready, strange, string, util, utilities, utils, vdbg

The ScoSocket.java Android example source code

/*
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.bluetooth;

import android.os.Handler;
import android.os.Message;
import android.os.PowerManager;
import android.os.PowerManager.WakeLock;
import android.util.Log;

/**
 * The Android Bluetooth API is not finalized, and *will* change. Use at your
 * own risk.
 *
 * Simple SCO Socket.
 * Currently in Android, there is no support for sending data over a SCO
 * socket - this is managed by the hardware link to the Bluetooth Chip. This
 * class is instead intended for management of the SCO socket lifetime, 
 * and is tailored for use with the headset / handsfree profiles.
 * @hide
 */
public class ScoSocket {
    private static final String TAG = "ScoSocket";
    private static final boolean DBG = true;
    private static final boolean VDBG = false;  // even more logging

    public static final int STATE_READY = 1;    // Ready for use. No threads or sockets
    public static final int STATE_ACCEPT = 2;   // accept() thread running
    public static final int STATE_CONNECTING = 3;  // connect() thread running
    public static final int STATE_CONNECTED = 4;   // connected, waiting for close()
    public static final int STATE_CLOSED = 5;   // was connected, now closed.

    private int mState;
    private int mNativeData;
    private Handler mHandler;
    private int mAcceptedCode;
    private int mConnectedCode;
    private int mClosedCode;

    private WakeLock mWakeLock;  // held while in STATE_CONNECTING

    static {
        classInitNative();
    }
    private native static void classInitNative();

    public ScoSocket(PowerManager pm, Handler handler, int acceptedCode, int connectedCode,
                     int closedCode) {
        initNative();
        mState = STATE_READY;
        mHandler = handler;
        mAcceptedCode = acceptedCode;
        mConnectedCode = connectedCode;
        mClosedCode = closedCode;
        mWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "ScoSocket");
        mWakeLock.setReferenceCounted(false);
        if (VDBG) log(this + " SCO OBJECT CTOR");
    }
    private native void initNative();

    protected void finalize() throws Throwable {
        try {
            if (VDBG) log(this + " SCO OBJECT DTOR");
            destroyNative();
            releaseWakeLockNow();
        } finally {
            super.finalize();
        }
    }
    private native void destroyNative();

    /** Connect this SCO socket to the given BT address.
     *  Does not block.
     */
    public synchronized boolean connect(String address, String name) {
        if (DBG) log("connect() " + this);
        if (mState != STATE_READY) {
            if (DBG) log("connect(): Bad state");
            return false;
        }
        acquireWakeLock();
        if (connectNative(address, name)) {
            mState = STATE_CONNECTING;
            return true;
        } else {
            mState = STATE_CLOSED;
            releaseWakeLockNow();
            return false;
        }
    }
    private native boolean connectNative(String address, String name);

    /** Accept incoming SCO connections.
     *  Does not block.
     */
    public synchronized boolean accept() {
        if (VDBG) log("accept() " + this);
        if (mState != STATE_READY) {
            if (DBG) log("Bad state");
            return false;
        }
        if (acceptNative()) {
            mState = STATE_ACCEPT;
            return true;
        } else {
            mState = STATE_CLOSED;
            return false;
        }
    }
    private native boolean acceptNative();

    public synchronized void close() {
        if (DBG) log(this + " SCO OBJECT close() mState = " + mState);
        acquireWakeLock();
        mState = STATE_CLOSED;
        closeNative();
        releaseWakeLock();
    }
    private native void closeNative();

    public synchronized int getState() {
        return mState;
    }

    private synchronized void onConnected(int result) {
        if (VDBG) log(this + " onConnected() mState = " + mState + " " + this);
        if (mState != STATE_CONNECTING) {
            if (DBG) log("Strange state, closing " + mState + " " + this);
            return;
        }
        if (result >= 0) {
            mState = STATE_CONNECTED;
        } else {
            mState = STATE_CLOSED;
        }
        mHandler.obtainMessage(mConnectedCode, mState, -1, this).sendToTarget();
        releaseWakeLockNow();
    }

    private synchronized void onAccepted(int result) {
        if (VDBG) log("onAccepted() " + this);
        if (mState != STATE_ACCEPT) {
            if (DBG) log("Strange state " + this);
            return;
        }
        if (result >= 0) {
            mState = STATE_CONNECTED;
        } else {
            mState = STATE_CLOSED;
        }
        mHandler.obtainMessage(mAcceptedCode, mState, -1, this).sendToTarget();
    }

    private synchronized void onClosed() {
        if (DBG) log("onClosed() " + this);
        if (mState != STATE_CLOSED) {
            mState = STATE_CLOSED;
            mHandler.obtainMessage(mClosedCode, mState, -1, this).sendToTarget();
            releaseWakeLock();
        }
    }

    private void acquireWakeLock() {
        if (!mWakeLock.isHeld()) {
            mWakeLock.acquire();
            if (VDBG) log("mWakeLock.acquire() " + this);
        }
    }

    private void releaseWakeLock() {
        if (mWakeLock.isHeld()) {
            // Keep apps processor awake for a further 2 seconds.
            // This is a hack to resolve issue http://b/1616263 - in which
            // we are left in a 80 mA power state when remotely terminating a
            // call while connected to BT headset "HTC BH S100 " with A2DP and
            // HFP profiles.
            if (VDBG) log("mWakeLock.release() in 2 sec" + this);
            mWakeLock.acquire(2000);
        }
    }

    private void releaseWakeLockNow() {
        if (mWakeLock.isHeld()) {
            if (VDBG) log("mWakeLock.release() now" + this);
            mWakeLock.release();
        }
    }

    private void log(String msg) {
        Log.d(TAG, msg);
    }
}