Java基础知识网络编程（TCP练习）

练习：复制文本

练习要求：把客户端的一个文件内容发到服务端，在服务端把数据存储到一个文件当中。相当于复制文件。

import java.io.*;import java.net.*;class TxtCopyTestClient{    public static void main(String[] args) throws Exception    {        Socket s=new Socket("192.168.1.6",10003);        BufferedReader bur=new BufferedReader(new InputStreamReader(new FileInputStream("client.txt")));        //BufferedWriter buwOut=new BufferedWriter(new OutputStreamWriter(s.getOutputStream()));        PrintWriter pw=new PrintWriter(s.getOutputStream(),true);        String line=null;        while((line=bur.readLine())!=null)        {            pw.println(line);        }        s.shutdownOutput();        BufferedReader burIn=new BufferedReader(new InputStreamReader(s.getInputStream()));        String str=burIn.readLine();        System.out.println(str);        bur.close();        s.close();    }}class TxtCopyTestServer{    public static void main(String[] args) throws Exception    {        ServerSocket ss=new ServerSocket(10003);        Socket s=ss.accept();        BufferedReader burIn=new BufferedReader(new InputStreamReader(s.getInputStream()));        PrintWriter pw=new PrintWriter(new FileOutputStream("server.txt"),true);        String line=null;        while((line=burIn.readLine())!=null)        {            pw.println(line);        }        pw.close();        PrintWriter pwOut=new PrintWriter(s.getOutputStream(),true);        pwOut.println("上传成功");        s.close();        ss.close();    }}

练习2：上传图片

import java.io.*;import java.net.*;class PicClient {    public static void main(String[] args) throws Exception    {        Socket s=new Socket("192.168.1.114",10003);        FileInputStream fis=new FileInputStream("pictest.jpg");        OutputStream os=s.getOutputStream();        byte[] buf=new byte[1024];        int len=0;        while((len=fis.read(buf))!=-1)        {            os.write(buf,0,len);        }        s.shutdownOutput();        InputStream is=s.getInputStream();        byte[] re=new byte[1024];        int length=is.read(re);        String str=new String(re,0,length);        System.out.println(str);        fis.close();        s.close();    }}class PicServer{    public static void main(String[] args)throws Exception    {        ServerSocket ss=new ServerSocket(10003);        Socket s=ss.accept();        InputStream is=s.getInputStream();        FileOutputStream fos=new FileOutputStream("serverpic.jpg");        byte[] buf=new byte[1024];        int len=0;        while((len=is.read(buf))!=-1)        {            fos.write(buf,0,len);        }        OutputStream os=s.getOutputStream();        os.write("上传成功".getBytes());        s.close();        ss.close();    }}

练习3：客户端并发上传图片

import java.io.*;import java.net.*;class  UploadByThreadClient{    public static void main(String[] args) throws Exception    {        if(args.length!=1)        {            System.out.println("请选择一张jpg图片");            return;        }        File file=new File(args[0]);        if(!(file.exists()&&file.isFile()))        {            System.out.println("该文件有问题，要么补存在，要么不是文件");            return ;        }        if(!file.getName().endsWith(".jpg"))        {            System.out.println("图片格式错误,请重新选择");            return ;        }        if(file.length()>1024*1024*5)        {            System.out.println("文件过大，没安好心");            return ;        }        Socket s = new Socket("192.168.1.114",10003);        FileInputStream fis = new FileInputStream("pictest.jpg");        OutputStream out = s.getOutputStream();        byte[] buf = new byte[1024];        int len = 0;        while((len=fis.read(buf))!=-1)        {            out.write(buf,0,len);        }        //告诉服务端数据已写完        s.shutdownOutput();        InputStream in = s.getInputStream();        byte[] bufIn = new byte[1024];        int num = in.read(bufIn);        System.out.println(new String(bufIn,0,num));        fis.close();        s.close();    }}class  UploadByThreadServer{    public static void main(String[] args) throws Exception    {        ServerSocket ss=new ServerSocket(10003);        while(true)        {            Socket s=ss.accept();            new Thread(new AcceptThread(s)).start();        }    }}class AcceptThread implements Runnable{    private Socket s;    AcceptThread(Socket s)    {        this.s=s;    }    public void run()    {        try        {            InputStream in = s.getInputStream();            String ip=s.getInetAddress().getHostAddress();            int count=1;            File def=new File(ip+"("+count+")"+".jpg");            while(def.exists())            {                def=new File(ip+"("+(count++)+")"+".jpg");            }            FileOutputStream fos = new FileOutputStream(def);            byte[] buf = new byte[1024];            int len = 0;            while((len=in.read(buf))!=-1)            {                fos.write(buf,0,len);            }            OutputStream out = s.getOutputStream();            out.write("上传成功".getBytes());            fos.close();            s.close();        }        catch (Exception e)        {            throw new RuntimeException("上传失败");        }    }}

练习4：客户端并发登陆

import java.io.*;import java.net.*;class LoginClient{    public static void main(String[] args)throws Exception     {        Socket s=new Socket("192.168.1.6",100010);        BufferedReader bur=new BufferedReader(new InputStreamReader(System.in));        PrintWriter pw=new PrintWriter(s.getOutputStream(),true);        BufferedReader burIn=new BufferedReader(new InputStreamReader(s.getInputStream()));        for(int i=0;i<3;i++)        {            String user=bur.readLine();            if(user==null)                break;            pw.println(user);            String info=burIn.readLine();            System.out.println("反馈信息为："+info);            if(info.contains("欢迎"))            {                System.out.println("登陆成功");                break;            }        }        bur.close();        s.close();    }}class LoginServer{    public static void main(String[] args) throws Exception     {        ServerSocket ss=new ServerSocket(100010);        while(true)        {            Socket s=ss.accept();            System.out.println("连接成功");            new Thread(new UserLoginThread(s)).start();        }    }}class UserLoginThread implements Runnable{    private Socket s;    UserLoginThread(Socket s)    {        this.s=s;    }    public void run()    {        try        {            BufferedReader burIn=new BufferedReader(new InputStreamReader(s.getInputStream()));            for(int i=0;i<3;i++)            {                String user=burIn.readLine();                System.out.println("发送来的用户名："+user);                if(user==null)                {                    System.out.println("为空"+user);                    break;                }                BufferedReader bur=new BufferedReader(new FileReader("user.txt"));                String line=null;                boolean flag=false;                while((line=bur.readLine())!=null)                {                    System.out.println("搜索到的用户名："+line);                    if(line.equals(user))                    {                        flag=true;                        break;                    }                }                if(flag)                {                    PrintWriter pw=new PrintWriter(s.getOutputStream(),true);                    pw.println(user+"欢迎您！");                    s.close();                    break;                }                else                {                    PrintWriter pw=new PrintWriter(s.getOutputStream(),true);                    pw.println("请输入正确的用户名");                }                bur.close();            }            s.close();        }        catch (Exception e)        {            throw new RuntimeException("登陆失败");        }    }}