问题描述

java中BufferedInputStream的方法问题

解决方案

while循环会结束的，InputStream流输入到达尾部时，br.read(buf)返回的就是-1了，就标识输入结束。
这个是由客户端发送的Socket决定的，客户端Socket发送完毕，这段代码读取发送数据也就结束了。

解决方案二：

客户端发送了什么内容？正常情况下可以打印出客户端发送过来的数据，打印完就结束了。另外，客户端发送完数据要给一个结束标记。

解决方案三：

服务器端

 import java.net.*;
import java.io.*;
public class  Server
{
    public static void main(String[] args) throws Exception
    {
        ServerSocket server = new ServerSocket(8888);
        System.out.println("Wait for connection...");
        Socket socket = server.accept();
        BufferedInputStream is = new BufferedInputStream(socket.getInputStream());
        byte[] buff = new byte[1024];
        int size;
        while((size = is.read(buff)) != -1){
            System.out.println(new String(buff,0,size));
        }
    }
}

客户端

 import java.net.*;
import java.io.*;
public class  Client
{
    public static void main(String[] args) throws Exception
    {
        Socket socket = new Socket("localhost",8888);
        BufferedOutputStream  out = new BufferedOutputStream(socket.getOutputStream());
        byte[] buff = new byte[2048];
        for(int i = 0 ; i < 2048 ; i ++){
            buff[i] = 'a';
        }
        out.write(buff);
        out.flush();//你可能没有写这个，我测试的时候，没写会出现socketexception:connection reset异常
        out.close();
        socket.close();
        System.out.println("Send Over!");
    }
}

解决方案四：

对应的客户端写入刘未关闭导致另一端等待输入流read阻塞了。解决办法：
服务器端：

        ServerSocket server;
        try {
            server = new ServerSocket(8800);
            System.out.println("Wait for connection...");
            Socket socket = server.accept();
            BufferedInputStream is = new BufferedInputStream(
                    socket.getInputStream());
            byte[] buff = new byte[1024];
            int size;
            while ((size = is.read(buff)) != -1) {
                System.out.println(new String(buff, 0, size));
            }

            OutputStream os = socket.getOutputStream();
            os.write("您好，我是Server端".getBytes());
            os.flush();
            os.close();
            System.out.println("ok,client send over.");
            server.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

客户端端：

 public static void main(String[] args) throws Exception
    {
        Socket s = new Socket("localhost",8800);
        OutputStream os = s.getOutputStream();
        os.write("您好，我是客户端".getBytes());
        os.close();

        InputStream in = s.getInputStream();
        byte[] buff = new byte[1024];
        BufferedInputStream is = new BufferedInputStream(in);
        int size;
        while((size = is.read(buff)) != -1){
            System.out.println(new String(buff,0,size));
        }
        System.out.println("over...");
        s.close();
    }

解决方案五：

服务器

import java.net.*;
import java.io.*;
public class  Server
{
    public static void main(String[] args) throws Exception
    {
        ServerSocket server = new ServerSocket(8888);
        System.out.println("Wait for connection...");
        Socket socket = server.accept();
        BufferedInputStream is = new BufferedInputStream(socket.getInputStream());
        byte[] buff = new byte[1024];
        int size;
        //当客户端的输出流没有close时，服务器端收不到-1，会一直在沉睡在while里面，
        while((size = is.read(buff)) != -1){
            String str = new String(buff,0,size);
            System.out.println(str);
            /****************************************************/
            if(str.indexOf('n') > 0){//存在消息结束标志
                break;
            }
            /*****************************************************/
        }
        //is.close();
        System.out.println("Received");
        System.out.println("Sending...");
        BufferedOutputStream  out = new BufferedOutputStream(socket.getOutputStream());
        out.write("你好，我是服务器".getBytes());
        out.flush();
        out.close();
        is.close();
        socket.close();
        System.out.println("Send Over!");
    }
}

客户端

import java.net.*;
import java.io.*;
public class  Client
{
    public static void main(String[] args) throws Exception
    {
        Socket socket = new Socket("localhost",8888);
        BufferedOutputStream  out = new BufferedOutputStream(socket.getOutputStream());
        /********************表示发送结束*****************************/
        out.write("你好，我是客户端n".getBytes());
        out.flush();
        //out.close();有这句话时，服务器可以读到一个-1
        System.out.println("Send Over!");
        System.out.println("Receiving...");
        BufferedInputStream is = new BufferedInputStream(socket.getInputStream());
        byte[] buff = new byte[1024];
        int size;
        while((size = is.read(buff)) != -1){
            System.out.println(new String(buff,0,size));
        }
        is.close();
        out.close();
        socket.close();
        System.out.println("Received!");
    }
}