Java在客户端打开一个套接字

Question

i can't figure out why my client socket keeps falling in an IOException. When it falls in the IOException i recreate my socket and so it will work again untill it falls again into the Exception and so on ...

the code should always read out an ip controller from my electrical installation. I cant change anything on the server side. I connect to it and when something happens it post it to the port and i want to be able to read it.

this is the opening socket code

    public KnxController(){
    try{
        System.out.println("Server started");
        clientSocket = new Socket(IP, PORT);
        outToServer = new DataOutputStream(clientSocket.getOutputStream());
    } catch (UnknownHostException e) {
        System.out.println("UnknownHostException: kan knx niet vinden");
    } catch (IOException e) {
        System.out.println("IOException knxcontroller: kan geen data sturen");
    }

and here i read out the data

        while(true){
        try {
            DataInputStream din=new DataInputStream(knxC.clientSocket.getInputStream()); 
            BufferedReader br = new BufferedReader(new InputStreamReader(din));
            String[] str=br.readLine().split("");  
            System.out.println(Arrays.toString(str));

        } catch (IOException e) {
            try {
                knxC.clientSocket = new Socket(knxC.IP, knxC.PORT);
            } catch (UnknownHostException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
        } catch(NullPointerException nex){
            try {
                knxC.clientSocket = new Socket(knxC.IP, knxC.PORT);
            } catch (UnknownHostException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }       
    }

it workes but far from good coding. any help on how to solve this would be appreciated.

Answer 1

cleaned the above code for anyone who's interested

opening a socket

    public KnxController(){
    do{
        setClientSocket();

        try {
            outToServer = new DataOutputStream(clientSocket.getOutputStream());
        } catch (IOException e) {
            log.error("IOException knxcontroller: kan geen data out stream starten naar knx");
        } catch (NullPointerException nEx){
            log.error("NullPointerException knxcontroller: geen knx host");
        }
    }while(clientSocket == null);

    KnxSocketListener knxL = new KnxSocketListener("KnxSocketListener", this);
    knxL.start();
}

    public void setClientSocket() {
    try {
        this.clientSocket = new Socket(IP, PORT);
    } catch (UnknownHostException e) {
        log.error("UnknownHostException: kan geen socket opbouwen met knx host");
    } catch (IOException e) {
        log.error("IOException: kan geen socket opbouwen met knx host");
    }
}

socketlistener in new thread public class KnxSocketListener

public KnxSocketListener(String name, KnxController knxC) {
      threadName = name;
      System.out.println("Creating " +  threadName );
      this.knxC = knxC;
}

public void start () {
      System.out.println("Starting " +  threadName );
      if (t == null) {
         t = new Thread (this, threadName);
         t.start ();
      }
}   

public void run()
{
    while(true){
        try {
            DataInputStream din = new DataInputStream(knxC.getClientSocket().getInputStream()); 
            BufferedReader br = new BufferedReader(new InputStreamReader(din));
            String[] str=br.readLine().split("");  
            System.out.println(Arrays.toString(str));
        } catch (IOException e) {
            knxC.setClientSocket();
        } catch(NullPointerException nex){
            knxC.setClientSocket();
        }       
    }
}