why IOException is triggered after receiving file from server (Socket programming)

Question

Here is the problem i am working on. 1)There is one server and one client. 2)server is connected with client. 3)server sends one file(.mp3). 4)after sending the file it sends some additional String data.

I am getting IOException after the file is sent, so i client is not reading additional string data.WHYYYYYYYY?

Here is the server code

 public class server {

ServerSocket server;
Socket socket;
FileInputStream fis;
FileOutputStream fos;
DataInputStream dis;
DataOutputStream dos;

public static void main(String args[])
{       
    server s=new server();
    s.connnect();
    s.init();
    s.send("f://song.mp3");     
}

public void connnect()
{
    try {
        server=new ServerSocket(8080);
        socket =server.accept();
    } catch (IOException e) {

    }       
}

public void init()
{
    try {
        dis=new DataInputStream(socket.getInputStream());
        dos=new DataOutputStream(socket.getOutputStream());
    } catch (IOException e) {
        e.printStackTrace();
    }       
}

public void send(String name)
{
    File f=new File(name);
    try {
        fis=new FileInputStream(f);
    } catch (FileNotFoundException e) {

        e.printStackTrace();
    }

    String nam=f.getName();

    try {
        dos.writeUTF(nam);
        System.out.println("header sent");

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

    byte[] buffer=new byte[1024];

    int read=-1;

    try {
        while((read=fis.read(buffer))!=-1)
        {
            dos.write(buffer, 0, read);
        }

        System.out.println("file "+name+" sent");

        dos.writeUTF("this is the msg which is not received by client because of IOexception in client side");

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

}

Client side code

 public class client {


ServerSocket server;
Socket socket;
FileInputStream fis;
FileOutputStream fos;
DataInputStream dis;
DataOutputStream dos;

public static void main(String args[])
{
    client s=new client();
    s.connect();
    s.init();
    try {           
    s.rec(s.dis.readUTF());      ///this the name of the String         
    } catch (IOException e) {

    }       
}

public void connect()
{
    try {
        socket=new Socket("127.0.0.1",8080);
        System.out.println("connected with server");
    } catch (UnknownHostException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }       
}

public void init()
{
    try {
        dis=new DataInputStream(socket.getInputStream());
        dos=new DataOutputStream(socket.getOutputStream());
    } catch (IOException e) {
        System.out.println("IO EXception in streams");
        e.printStackTrace();
    }       
}

public void rec(String filename)
{
    File f=new File("f://abc");
    f.mkdirs();     
    File temp=new File(f,filename);     
    try {
        fos=new FileOutputStream(temp);
    } catch (FileNotFoundException e) {

        e.printStackTrace();
    }

    byte[] buffer=new byte[1024];
    int read=-1;

    System.out.println("started reading file"+filename);

    try {           
        while((read=dis.read(buffer))!=-1)
        {
            fos.write(buffer, 0, read);
        }

        String FINAL_MSG=dis.readUTF();
        System.out.println("ended "+FINAL_MSG);

    } 
    catch (IOException e) {
        System.out.println("why IO exception?");
    }       
}

public void sendFile(String name)
{
    File f=new File("f://abc");
    f.mkdirs();

    File temp=new File(f,name);

    try {
        fos=new FileOutputStream(temp);
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    byte[] buffer=new byte[1024];
    int read=-1;

    try {
        while((read=dis.read(buffer))!=-1)
        {
            fos.write(buffer, 0, read);
        }
    } 
    catch(SocketException e)
    {
        System.out.println(name+" has end"+" "+(socket==null));

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

}

I want to read the additional string data (FINAL_MSG). how it is possible?

Server output

header sent     
file f://song.mp3 sent       
Final MSG is sent from server side 

Client output

connected with server    
started reading filesong.mp3     

java.net.SocketException: Connection reset by peer: socket write error
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(Unknown Source)
at java.net.SocketOutputStream.write(Unknown Source)
at java.io.DataOutputStream.write(Unknown Source)
at s1.send(s1.java:87) at s1.main(s1.java:30)

why IO exception?

Answer 1

Your Server program is terminated before client could read all data resulting into IO Exception.

Your Server program is sending a mp3 file, then printing message file sent, again writing data over the socket and then since nothing is left to do, it is terminated/ends so server socket is closed, which in turn causes IO Exception in the client program.