[Java] send Vector through TCP socket

Dear all,

I'm writing a Java program to send a vector through TCP socket. On client side, user can click a button "Send" to send a vector to server side without limitation (means allow to click many times). On the server side, receive the vector and store into database. In my case, it's work when the first clicking on client side, however, the content of vector on server side is unchange no matter click the button how many times on client side...it seems only received the first vector sent by client...
any expert know why and how to solve it? Thanks a lot !

Code as follows:
<Client side--method call in the button>

//dout = new DataOutputStream( socket.getOutputStream() );
//oos = new ObjectOutputStream(dout);
protected void sendRecord (Vector vr){
      try {
                oos.writeObject(vr);
                oos.flush();                
     } catch( IOException ie ) {    System.out.println( ie );}
}


<Sever side>

public void run() {
                 try{
             din =new DataInputStream(socket.getInputStream());
             ois = new ObjectInputStream(din);

             while (true) {
                  try{
                                v1 = (Vector) ois.readObject();
                                System.out.println("Vector to string :" + v1.toString());
                  }catch (IOException ioe){      break;      }
                   catch (IOException ee) {      break;      }
                   catch (ClassNotFoundException cnfe){      break;      }
              }
                 } catch( EOFException ie ) { }
                    catch (IOException ee) { }
}

<Server Output when click the button on client side>
Vector to string : [abc, cde] // Input abc & cde and add into vector on client side
Vector to string : [abc, cde] // Input xyz & opq and add into vector on client side
Vector to string : [abc, cde] // Input nothing
.............
 

adidazAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

JaaxArchitectCommented:
I think it is cos the you are not reading from the socket afresh. You are re-reading what has already been fetched from the dataInputStream.

Try this:
In the try inside the while, include the data fetching from the socket
while(true){
try{
 din =new DataInputStream(socket.getInputStream());
  ois = new ObjectInputStream(din);
  v1 = (Vector) ois.readObject();
  System.out.println("Vector to string :" + v1.toString());
....



0
adidazAuthor Commented:
Thanks Jaax, i tried before and exception occur (I think it's because using different input stream).
In fact, i have tried to send a string object instead of vector and result is fine. Code as follows:

<Client side>
protected void sendRecord (String recs){
      try {
                oos.writeObject(recs);
                oos.flush();                
     } catch( IOException ie ) {    System.out.println( ie );}
}

<Server side>
....
while (true) {
                  try{
                                recInString = (String) ois.readObject();
                                System.out.println("String :" + recInString);
                  }catch (IOException ioe){      break;      }
.....

<Server Output when click the button on client side>
String : abc_cde  // Input abc_cde on client side
String : xyz_opq  // Input xyz_opq on client side

Don't know why it's not work when using vector....
0
ksivananthCommented:
create a copy of the vector and send to the server!
0
Get expert help—faster!

Need expert help—fast? Use the Help Bell for personalized assistance getting answers to your important questions.

adidazAuthor Commented:
ksivananth, do you mean i need revise the code on client side as follows:

<Client side>
//Vector v2 = new Vector();
protected void sendRecord (Vector vr){
     this.v2.clear();    
     this.v2 = vr;
      try {
                oos.writeObject(v2);
                oos.flush();                
     } catch( IOException ie ) {    System.out.println( ie );}
}

Tried and same result...
I print the result on client side and output is fine always.
Anyway, thanks.
0
ksivananthCommented:
try this,

protected void sendRecord (Vector vr){
     Vector v2 = new Vector() ;
    Enumeration e = vr.elements();
    while( e.hasMoreElements() ) v2.addElement( e.nextElement() );
      try {
                oos.writeObject(v2);
                oos.flush();                
     } catch( IOException ie ) {    System.out.println( ie );}
}
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
adidazAuthor Commented:
oic...I only copy the pointers...I understand your point now.
This is exactly what i need. Thanks a lot.
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Java

From novice to tech pro — start learning today.