在tcp通訊中，一般都是阻塞的，如果要實現非阻塞，我們可以使用多執行緒也可以使用nio中相關的類。這裡我使用的是多執行緒的方式實現非阻塞。
伺服器端：
1.建立ServerSocket物件，繫結監聽埠；
2.呼叫accept()方法對客戶端進行監聽；
3.使用多執行緒對使用者進行讀操作，並反饋；
客戶端：
1.建立Socket物件，通過IP和埠號和伺服器進行連線；
2.分別使用多執行緒對伺服器端進行讀寫操作；
程式碼如下：
伺服器端：

package sency.one;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import
 
 java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;

public class Server {
    private ServerSocket ss;
    private int port = 8000;

    public Server() throws IOException {
        // 建立接收端的ServerSocket
        ss = new ServerSocket(port);
        System.out.println("伺服器啟動!!!");
    }

    public
 
 static void main(String args[]) throws IOException {
        new Server().service();
    }

    private void service() {
        // TODO Auto-generated method stub
        while (true) {
            Socket socket = null;
            try {
                // 通過accept()方法進行監聽，返回一個socket
                socket = ss.accept();
                DataOutputStream os = new
 
 DataOutputStream(socket.getOutputStream());
package sency.one;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;

public class Server {
    private ServerSocket ss;
    private int port = 8000;

    public Server() throws IOException {
        // 建立接收端的ServerSocket
        ss = new ServerSocket(port);
        System.out.println("伺服器啟動!!!");
    }

    public static void main(String args[]) throws IOException {
        new Server().service();
    }

    private void service() {
        // TODO Auto-generated method stub
        while (true) {
            Socket socket = null;
            try {
                // 通過accept()方法進行監聽，返回一個socket
                socket = ss.accept();
                DataOutputStream os = new DataOutputStream(socket.getOutputStream());
                os.writeUTF("Welcome!");
                os.flush();
                //輸出客戶端埠
                if (socket.isConnected()) {
                    System.out.println("Port:" + socket.getPort());
                }
                // 採用多執行緒的方式處理
                // 收資訊執行緒
                Thread receiveThread = new Thread(new ReHandler(socket));
                receiveThread.start();

            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

    // 收資訊
    class ReHandler implements Runnable {
        private Socket socket = null;

        public ReHandler(Socket socket) {
            this.socket = socket;
        }
        public void run() {
            try {
                printMsg(socket);
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                try {
                    if (socket != null) {
                        socket.close();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }



    // 在伺服器端輸出客戶端傳送的資訊
    private void printMsg(Socket socket) throws IOException {
        DataInputStream is = new DataInputStream(socket.getInputStream());      
        String msg = "";
        while ((msg = is.readUTF()) != null) {
            System.out.println("來自："+socket.getInetAddress()+"--"+socket.getPort());
            System.out.println("#Client:" + msg);
            if (msg.equals("bye")) {
                break;
            }
            sendEcho(socket,msg);
        }
        is.close();
    }

    // 向客戶端傳送資訊
    private void sendEcho(Socket socket,String msg) throws IOException {

        if(msg!=null){
            DataOutputStream os = new DataOutputStream(socket.getOutputStream());
            os.writeUTF("#Server:收到"+msg);
            os.flush();
        }
    }

}

客戶端：

package sency.one;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;

public class Client {
    private Socket socket;
    private String host = "localhost";
    private int port = 8000;

    public Client() throws IOException {
        socket = new Socket(host, port);
        System.out.println("客戶端啟動!!!");
        System.out.println("Port:"+socket.getLocalPort());
    }

    public static void main(String args[]) throws IOException {
        new Client().talk();
    }

    private void talk() {
        // TODO Auto-generated method stub
        // 採用多執行緒分別進行收發資訊
        // 傳送執行緒
        Thread sendThread = new Thread(new SendHandler());
        sendThread.start();

        // 收執行緒
        Thread reThread = new Thread(new ReHandler());
        reThread.start();
    }

    class SendHandler implements Runnable {
        public void run() {
            // TODO Auto-generated method stub
            try {
                sendMsg();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }finally {
                try {
                    if (socket != null) {
                        socket.close();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }

    class ReHandler implements Runnable {

        public void run() {
            // TODO Auto-generated method stub
            try {
                receiveMsg();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }finally {
                try {
                    if (socket != null) {
                        socket.close();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }

    //發信息
    public void sendMsg() throws IOException {
        DataOutputStream os = new DataOutputStream(socket.getOutputStream());
        DataInputStream is = new DataInputStream(System.in);
        String msg = null;
        while ((msg = is.readLine()) != null) {
            System.out.println("#Client:" + msg);
            os.writeUTF(msg);
            os.flush();
            if(msg.equals("bye")){
                break;
            }
        }   
        os.close();
        is.close();
    }

    //收資訊
    private void receiveMsg() throws IOException{
        DataInputStream is = new DataInputStream(socket.getInputStream());
        String msg = null;
        while((msg = is.readUTF())!=null){
            System.out.println("#Service:"+msg);
            if(msg.equals("bye")){
                break;
            }
        }
        is.close();
    }

}

遇到的問題：
我不知道有沒有人和我一樣在讀寫的時候用了BufferedReader和BufferedWriter，以至於在後面使用readLine()方法時儘管是多執行緒也一直處於阻塞狀態，我找了一下午，後來改成使用DataOutput/InputStream以及對應的readUTF()和writeUTF()方法，這個問題就解決了，具體原因我想了很久也沒想明白，有個猜測不確定，等下週問了老師得到準確的答案再來說吧！！！
立個Flag：接下來有時間的話自己再用nio實現一下非阻塞通訊，到時候來更博！