Android编程：双工tcp客户端中应用RxJava

本文博客链接:http://blog.csdn.net/jdh99,作者:jdh,转载请注明.

环境：

主机:WIN10

开发环境:Android Studio 2.2 Preview 3

RxJava版本：2.0.1

RxAndroid版本：2.0.1

说明：

在《Android编程：双工tcp客户端》文中用双线程处理了tcp客户端的发送和接收。现在用RxJava对此客户端代码进行优化：

• 用RxJava创建连接，替代之前的创建连接线程
• 用RxJava断开连接，替代之前的断开连接线程
• 用RxJava推送接收到的网络帧，替代之前的观察者模式
• 用RxJava推送创建成功消息，连接异常中断消息。之前不能推送，只能轮询连接状态

代码中用了lambda机制，在android studio需要安装插件retrolambda，可以参考安装：

Android 中使用Lambda表达式

源码：

Events.Java

package com.bazhangkeji.classroom.common;

import java.net.DatagramPacket;

public class Events {
    private Events() {

    }

    public static class UdpReceiveFrame {
        public DatagramPacket datagramPacket;
    }

    public static class TcpReceiveFrame {
        public DatagramPacket datagramPacket;
    }

    public static class TcpMakeConnectSuccess {
    }

    public static class TcpExceptionClose {

    }
}

TcpClient.java

package com.bazhangkeji.classroom.net;

import android.util.Log;

import com.bazhangkeji.classroom.Config;
import com.bazhangkeji.classroom.common.Crc16;
import com.bazhangkeji.classroom.common.Events;
import com.bazhangkeji.classroom.common.RxBus;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.DatagramPacket;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketAddress;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

import io.reactivex.BackpressureStrategy;
import io.reactivex.Flowable;
import io.reactivex.schedulers.Schedulers;

public class TcpClient implements Config, Protocol, Runnable {
    private static final String TAG_LOG = "TcpClient";
    private static final int MAX_FRAME_LENGTH = 2048;
    private static final int CONNECT_TIME_OUT = 3000;
    private static TcpClient tcpClient;
    private boolean isConnected = false;

    private Socket tcpSocket;
    private InputStream inputSteam;
    private OutputStream outputStream;

    private String serverIp = "";
    private int serverPort;

    private List<NetSendParameter> sendListCache;
    private List<NetSendParameter> sendList;
    private ReadWriteLock sendListCacheLock;

    // 线程锁:当前发送线程全部发送完成后就自锁等待
    private final byte[] lockSendThread = new byte[0];
    // 线程锁:当前不需要侦听则自锁等待
    private final byte[] lockReceiveThread = new byte[0];


    public static TcpClient getInstance() {
        if (tcpClient == null) {
            tcpClient = new TcpClient();
            new Thread(TcpClient.getInstance()).start();
        }
        return tcpClient;
    }

    private TcpClient()
    {
        sendListCache = new ArrayList<>();
        sendList = new ArrayList<>();
        sendListCacheLock = new ReentrantReadWriteLock();

        new Thread(new SendThread()).start();
    }

    /**
     * 连接服务器
     * @param ip: 服务器ip
     * @param port: 服务器端口
     */
    public synchronized void makeConnect(String ip, int port) {
        if (isConnected) {
            if (this.serverIp.equals(ip) && this.serverPort == port) {
                Events.TcpMakeConnectSuccess event = new Events.TcpMakeConnectSuccess();
                RxBus.getInstance().send(event);
                return;
            }
        }

        Flowable.create(e -> {
            e.onNext(new NetAddress(ip, port));
            e.onComplete();
        }, BackpressureStrategy.DROP)
                .observeOn(Schedulers.io())
                .subscribe(t -> startMakeConnect((NetAddress)t));

//        NetAddress netAddress = new NetAddress(ip, port);
//        Flowable.create(new FlowableOnSubscribe<NetAddress>() {
//            @Override
//            public void subscribe(FlowableEmitter<NetAddress> e) throws Exception {
//                Log.e(TAG_LOG, "subscribe!!!!!!!!!!!!!!!!!!!");
//                e.onNext(netAddress);
//                e.onComplete();
//            }
//        }, BackpressureStrategy.DROP).
//                observeOn(Schedulers.io()).
//                subscribe(new Consumer<NetAddress>() {
//                    @Override
//                    public void accept(NetAddress netAddress1) throws Exception {
//                        Log.e(TAG_LOG, "accept!!!!!!!!!!!!!!!!!!!");
//                        startMakeConnect(netAddress1);
//                    }
//        });
    }

    private void startMakeConnect(NetAddress netAddress) {
        if (isConnected) {
            tcpSocketClose();
        }

        try {
            tcpSocket = new Socket();
            SocketAddress address = new InetSocketAddress(netAddress.ip, netAddress.port);
            tcpSocket.connect(address, CONNECT_TIME_OUT);

            inputSteam = tcpSocket.getInputStream();
            outputStream = tcpSocket.getOutputStream();
            isConnected = true;

            serverIp = netAddress.ip;
            serverPort = netAddress.port;

            unlockReceiveThread();
            Log.e(TAG_LOG, "make connect success!!!!!!!!!!!!!!!!!!!");

            Events.TcpMakeConnectSuccess event = new Events.TcpMakeConnectSuccess();
            RxBus.getInstance().send(event);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private void tcpSocketClose() {
        isConnected = false;
        try {
            tcpSocket.close();
            Log.i(TAG_LOG, "断开连接");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private void unlockReceiveThread() {
        synchronized (lockReceiveThread) {
            lockReceiveThread.notifyAll();
        }
    }

    /**
     * 关闭连接
     */
    public void close() {
        if (isConnected) {
            Flowable.create(e -> {
                e.onNext("");
                e.onComplete();
            }, BackpressureStrategy.DROP)
                    .observeOn(Schedulers.io())
                    .subscribe(t -> tcpSocketClose());
        }
    }

    /**
     * 当前是否连接.
     * @return 连接返回true,失败返回false
     */
    public boolean isConnected() {
        return isConnected;
    }

    /**
     * 得到服务器ip
     * @return 服务器ip
     */
    public String getServerIp() {
        return serverIp;
    }

    /**
     * 得到服务器端口
     * @return 服务器端口
     */
    public int getServerPort() {
        return serverPort;
    }

    /**
     * 发送
     * @param netSendParameter 发送参数
     */
    public void send(NetSendParameter netSendParameter) {
        if (isConnected) {
            sendListCacheLock.writeLock().lock();
            sendListCache.add(netSendParameter);
            sendListCacheLock.writeLock().unlock();

            unlockSendThread();
        }
    }

    private void unlockSendThread() {
        synchronized (lockSendThread) {
            lockSendThread.notifyAll();
        }
    }

    @Override
    public void run() {
        byte[] bufferReceive = new byte[MAX_FRAME_LENGTH];
        DatagramPacket receiveFrame = new DatagramPacket(bufferReceive, MAX_FRAME_LENGTH);

        while (true) {
            if (!isConnected) {
                lockReceiveThread();
            }

            try {
                int length = inputSteam.read(receiveFrame.getData());
                if (length > 0) {
                    receiveFrame.setLength(length);
                    if (FilterFrame.filter(receiveFrame)) {
                        Events.TcpReceiveFrame tcpReceiveFrame = new Events.TcpReceiveFrame();
                        tcpReceiveFrame.datagramPacket = receiveFrame;
                        RxBus.getInstance().send(tcpReceiveFrame);
                    }
                } else {
                    exceptionClose();
                }
            } catch (IOException e) {
                e.printStackTrace();
                exceptionClose();
            }
        }
    }

    private void lockReceiveThread() {
        synchronized (lockReceiveThread) {
            try {
                lockReceiveThread.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    private void exceptionClose() {
        if (!tcpSocket.isClosed()) {
            Log.i(TAG_LOG, "closed1111111111!!!!");
            boolean isExceptionClose = isConnected;
            tcpSocketClose();

            if (isExceptionClose) {
                Events.TcpExceptionClose event = new Events.TcpExceptionClose();
                RxBus.getInstance().send(event);
            }
        }
        if (!tcpSocket.isConnected()) {
            Log.i(TAG_LOG, "disconnect11111111111!!!!");
        }
    }

    private class SendThread implements Runnable {
        @Override
        public void run() {
            while (true) {
                if (!isConnected) {
                    clearCache();
                    sendList.clear();
                    lockThread();
                }

                copyCache();
                if (!sendList.isEmpty()) {
                    sendFrame();
                    sendList.clear();
                } else {
                    lockThread();
                }
            }
        }

        private void clearCache() {
            sendListCacheLock.writeLock().lock();
            sendListCache.clear();
            sendListCacheLock.writeLock().unlock();
        }

        private void lockThread() {
            synchronized (lockSendThread) {
                try {
                    lockSendThread.wait();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }

        private void copyCache() {
            sendListCacheLock.readLock().lock();
            if (sendListCache.isEmpty()) {
                sendListCacheLock.readLock().unlock();
            } else {
                sendList.addAll(sendListCache);
                sendListCacheLock.readLock().unlock();
                clearCache();
            }
        }

        private void sendFrame() {
            for (NetSendParameter parameter: sendList) {
                send(parameter);
            }
        }

        private void send(NetSendParameter netSendParameter) {
            byte[] arr = new byte[MAX_FRAME_LENGTH];
            int j = 0;
            arr[j++] = (byte)(FRAME_HEAD >> 8);
            arr[j++] = (byte)FRAME_HEAD;
            arr[j++] = (byte)PROTOCOL_VERSION_CODE;
            arr[j++] = (byte)(netSendParameter.cmd >> 8);
            arr[j++] = (byte)netSendParameter.cmd;

            if (netSendParameter.frameIndex == 0) {
                int frameIndex = FrameIndex.getInstance().get();
                arr[j++] = (byte)(frameIndex >> 8);
                arr[j++] = (byte)frameIndex;
                FrameIndex.getInstance().increment();
            } else {
                arr[j++] = (byte) (netSendParameter.frameIndex >> 8);
                arr[j++] = (byte) netSendParameter.frameIndex;
            }

            // 报文长度
            arr[j++] = (byte)(netSendParameter.length >> 8);
            arr[j++] = (byte)netSendParameter.length;

            int crc = Crc16.calc(netSendParameter.frameBody, 0, netSendParameter.length);
            arr[j++] = (byte)(crc >> 8);
            arr[j++] = (byte)crc;

            // 正文
            for (int i = 0; i < netSendParameter.length; i++) {
                arr[j++] = netSendParameter.frameBody[i];
            }

            try {
                outputStream.write(arr, 0, j);
            } catch (IOException e) {
                e.printStackTrace();
                tcpSocketClose();
            }
        }
    }

    private class NetAddress {
        String ip;
        int port;

        NetAddress(String ip, int port) {
            this.ip = ip;
            this.port = port;
        }
    }
}

创建连接：

TcpClient.getInstance().makeConnect("115.28.86.171", 21801);

TcpClient.getInstance().close();

                NetSendParameter parameter = new NetSendParameter();
                parameter.cmd = 3;
                TcpClient.getInstance().send(parameter);

            RxBus.getInstance().toObserverable(Events.TcpMakeConnectSuccess.class)
                    .subscribe(t -> Log.e(TAG, "------------------------------------MAKE CONNECT"));

            RxBus.getInstance().toObserverable(Events.TcpExceptionClose.class)
                    .subscribe(t -> Log.e(TAG, "--------------------------CLOSE"));

Android编程：双工tcp客户端中应用RxJava