Unable to populate String.

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Hello,

I am creating a client/server application that verifies math equations for addition, subtraction, and division. I think I just need someone else’s eyes to possibly see where I am going wrong with this. Everything seems to be working fine except for one variable. This is the String serverAnswer variable in my Server class. When I debug the application, the serverAnswer variable remains null, can anyone tell me what I’m doing wrong? I wrote the code for where it should be populated in the processConnection() method of my server class. I know this is a lot of code, but it is needed to debug the application. Thank you.

Java Syntax (Toggle Plain Text)
import java.io.EOFException;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
import java.lang.*;
import sun.io.Converters;
import javax.script.*;
 
public class Server extends JFrame 
{
   private JTextField enterField; // inputs message from user
   private JTextArea displayArea; // display information to user
   private ObjectOutputStream output; // output stream to client
   private ObjectInputStream input; // input stream from client
   private ServerSocket server; // server socket
   private Socket connection; // connection to client
   private int counter = 1; // counter of number of connections
   String serverAnswer;
   //private String serverAnswer;
 
   // set up GUI
   public Server()
   {
      super( "Server" );
 
      enterField = new JTextField(); // create enterField
      enterField.setEditable( false );
      enterField.addActionListener(
         new ActionListener() 
         {
            // send message to client
            public void actionPerformed( ActionEvent event )
            {
               sendData( event.getActionCommand() );
               enterField.setText( "" );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener
 
      add( enterField, BorderLayout.NORTH );
 
      displayArea = new JTextArea(); // create displayArea
      add( new JScrollPane( displayArea ), BorderLayout.CENTER );
 
      setSize( 300, 150 ); // set size of window
      setVisible( true ); // show window
   } // end Server constructor
 
   // set up and run server 
   public void runServer()
   {
      try // set up server to receive connections; process connections
      {
         server = new ServerSocket( 12345, 100 ); // create ServerSocket
 
         while ( true ) 
         {
            try 
            {
               waitForConnection(); // wait for a connection
               getStreams(); // get input & output streams
               processConnection(); // process connection
            } // end try
            catch ( EOFException eofException ) 
            {
               displayMessage( "\nServer terminated connection" );
            } // end catch
            finally 
            {
               closeConnection(); //  close connection
               counter++;
            } // end finally
         } // end while
      } // end try
      catch ( IOException ioException ) 
      {
         ioException.printStackTrace();
      } // end catch
   } // end method runServer
 
   // wait for connection to arrive, then display connection info
   private void waitForConnection() throws IOException
   {
      displayMessage( "Waiting for connection\n" );
      connection = server.accept(); // allow server to accept connection            
      displayMessage( "Connection " + counter + " received from: " +
         connection.getInetAddress().getHostName() );
   } // end method waitForConnection
 
   // get streams to send and receive data
   private void getStreams() throws IOException
   {
      // set up output stream for objects
      output = new ObjectOutputStream( connection.getOutputStream() );
      output.flush(); // flush output buffer to send header information
 
      // set up input stream for objects
      input = new ObjectInputStream( connection.getInputStream() );
 
      displayMessage( "\nGot I/O streams\n" );
   } // end method getStreams
 
   // process connection with client
   private void processConnection() throws IOException
   {
 
      String message = "Connection successful";
      sendData( message ); // send connection successful message
 
 
      // enable enterField so server user can send messages
      setTextFieldEditable( false );
      ScriptEngine engine = new ScriptEngineManager().getEngineByExtension("js");
 
      do // process messages sent from client
 
      { 
         try // read message and display it
         {
            message = ( String ) input.readObject(); // read new message
          if (message.contains("+")){
            Object result = engine.eval(message);
            serverAnswer = String.valueOf(result);
            }
          else if(message.contains("/")){
            Object result = engine.eval(message);
            serverAnswer = String.valueOf(result);
          }
          else if(message.contains("-")){
            Object result = engine.eval(message);
            serverAnswer = String.valueOf(result);
          }
          else if (message.equals(serverAnswer)){
              displayMessage("\n" + "You are correct");
          }
          else{
            displayMessage("\n" + "Incorrect!");
 
          }
 
            //displayMessage("\n" + serverAnswer);
 
        }
        catch (ScriptException e) {
            // Something went wrong
            e.printStackTrace();
        }
        catch (ClassNotFoundException classNotFoundException){
            displayMessage ( "\nUnknown object type received" );
        }
 
 
            displayMessage( "\n" + message ); // display message
         } // end try
        /* catch ( ClassNotFoundException classNotFoundException )
         {
            displayMessage( "\nUnknown object type received" );
         } // end catch
 
      } */while ( !message.equals( "CLIENT>>> TERMINATE" ) );
 
 
   } // end method processConnection
 
 
   // close streams and socket
   private void closeConnection() 
   {
      displayMessage( "\nTerminating connection\n" );
      setTextFieldEditable( false ); // disable enterField
 
      try 
      {
         output.close(); // close output stream
         input.close(); // close input stream
         connection.close(); // close socket
      } // end try
      catch ( IOException ioException ) 
      {
         ioException.printStackTrace();
      } // end catch
   } // end method closeConnection
 
   // send message to client
   private void sendData( String message )
   {
      try // send object to client
      {
         output.writeObject( "SERVER>>> " + message );
         output.flush(); // flush output to client
         displayMessage( "\nSERVER>>> " + message );
      } // end try
      catch ( IOException ioException ) 
      {
         displayArea.append( "\nError writing object" );
      } // end catch
   } // end method sendData
 
   // manipulates displayArea in the event-dispatch thread
   private void displayMessage( final String messageToDisplay )
   {
      SwingUtilities.invokeLater(
         new Runnable() 
         {
            public void run() // updates displayArea
            {
               displayArea.append( messageToDisplay ); // append message
            } // end method run
         } // end anonymous inner class
      ); // end call to SwingUtilities.invokeLater
   } // end method displayMessage
 
   // manipulates enterField in the event-dispatch thread
   private void setTextFieldEditable( final boolean editable )
   {
      SwingUtilities.invokeLater(
         new Runnable()
         {
            public void run() // sets enterField's editability
            {
               enterField.setEditable( editable );
            } // end method run
         }  // end inner class
      ); // end call to SwingUtilities.invokeLater
   } // end method setTextFieldEditable
} // end class Server
import java.io.EOFException;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
import java.lang.*;
import sun.io.Converters;
import javax.script.*;

public class Server extends JFrame 
{
   private JTextField enterField; // inputs message from user
   private JTextArea displayArea; // display information to user
   private ObjectOutputStream output; // output stream to client
   private ObjectInputStream input; // input stream from client
   private ServerSocket server; // server socket
   private Socket connection; // connection to client
   private int counter = 1; // counter of number of connections
   String serverAnswer;
   //private String serverAnswer;

   // set up GUI
   public Server()
   {
      super( "Server" );

      enterField = new JTextField(); // create enterField
      enterField.setEditable( false );
      enterField.addActionListener(
         new ActionListener() 
         {
            // send message to client
            public void actionPerformed( ActionEvent event )
            {
               sendData( event.getActionCommand() );
               enterField.setText( "" );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      add( enterField, BorderLayout.NORTH );

      displayArea = new JTextArea(); // create displayArea
      add( new JScrollPane( displayArea ), BorderLayout.CENTER );

      setSize( 300, 150 ); // set size of window
      setVisible( true ); // show window
   } // end Server constructor

   // set up and run server 
   public void runServer()
   {
      try // set up server to receive connections; process connections
      {
         server = new ServerSocket( 12345, 100 ); // create ServerSocket

         while ( true ) 
         {
            try 
            {
               waitForConnection(); // wait for a connection
               getStreams(); // get input & output streams
               processConnection(); // process connection
            } // end try
            catch ( EOFException eofException ) 
            {
               displayMessage( "\nServer terminated connection" );
            } // end catch
            finally 
            {
               closeConnection(); //  close connection
               counter++;
            } // end finally
         } // end while
      } // end try
      catch ( IOException ioException ) 
      {
         ioException.printStackTrace();
      } // end catch
   } // end method runServer

   // wait for connection to arrive, then display connection info
   private void waitForConnection() throws IOException
   {
      displayMessage( "Waiting for connection\n" );
      connection = server.accept(); // allow server to accept connection            
      displayMessage( "Connection " + counter + " received from: " +
         connection.getInetAddress().getHostName() );
   } // end method waitForConnection

   // get streams to send and receive data
   private void getStreams() throws IOException
   {
      // set up output stream for objects
      output = new ObjectOutputStream( connection.getOutputStream() );
      output.flush(); // flush output buffer to send header information

      // set up input stream for objects
      input = new ObjectInputStream( connection.getInputStream() );

      displayMessage( "\nGot I/O streams\n" );
   } // end method getStreams

   // process connection with client
   private void processConnection() throws IOException
   {
      
      String message = "Connection successful";
      sendData( message ); // send connection successful message
      

      // enable enterField so server user can send messages
      setTextFieldEditable( false );
      ScriptEngine engine = new ScriptEngineManager().getEngineByExtension("js");

      do // process messages sent from client

      { 
         try // read message and display it
         {
            message = ( String ) input.readObject(); // read new message
          if (message.contains("+")){
            Object result = engine.eval(message);
            serverAnswer = String.valueOf(result);
            }
          else if(message.contains("/")){
            Object result = engine.eval(message);
            serverAnswer = String.valueOf(result);
          }
          else if(message.contains("-")){
            Object result = engine.eval(message);
            serverAnswer = String.valueOf(result);
          }
          else if (message.equals(serverAnswer)){
              displayMessage("\n" + "You are correct");
          }
          else{
            displayMessage("\n" + "Incorrect!");

          }
            
            //displayMessage("\n" + serverAnswer);

        }
        catch (ScriptException e) {
            // Something went wrong
            e.printStackTrace();
        }
        catch (ClassNotFoundException classNotFoundException){
            displayMessage ( "\nUnknown object type received" );
        }


            displayMessage( "\n" + message ); // display message
         } // end try
        /* catch ( ClassNotFoundException classNotFoundException )
         {
            displayMessage( "\nUnknown object type received" );
         } // end catch

      } */while ( !message.equals( "CLIENT>>> TERMINATE" ) );


   } // end method processConnection
   

   // close streams and socket
   private void closeConnection() 
   {
      displayMessage( "\nTerminating connection\n" );
      setTextFieldEditable( false ); // disable enterField

      try 
      {
         output.close(); // close output stream
         input.close(); // close input stream
         connection.close(); // close socket
      } // end try
      catch ( IOException ioException ) 
      {
         ioException.printStackTrace();
      } // end catch
   } // end method closeConnection

   // send message to client
   private void sendData( String message )
   {
      try // send object to client
      {
         output.writeObject( "SERVER>>> " + message );
         output.flush(); // flush output to client
         displayMessage( "\nSERVER>>> " + message );
      } // end try
      catch ( IOException ioException ) 
      {
         displayArea.append( "\nError writing object" );
      } // end catch
   } // end method sendData

   // manipulates displayArea in the event-dispatch thread
   private void displayMessage( final String messageToDisplay )
   {
      SwingUtilities.invokeLater(
         new Runnable() 
         {
            public void run() // updates displayArea
            {
               displayArea.append( messageToDisplay ); // append message
            } // end method run
         } // end anonymous inner class
      ); // end call to SwingUtilities.invokeLater
   } // end method displayMessage

   // manipulates enterField in the event-dispatch thread
   private void setTextFieldEditable( final boolean editable )
   {
      SwingUtilities.invokeLater(
         new Runnable()
         {
            public void run() // sets enterField's editability
            {
               enterField.setEditable( editable );
            } // end method run
         }  // end inner class
      ); // end call to SwingUtilities.invokeLater
   } // end method setTextFieldEditable
} // end class Server

Java Syntax (Toggle Plain Text)
import javax.swing.JFrame;
 
public class ServerTest
{
   public static void main( String args[] )
   {
      Server application = new Server(); // create server
      application.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
      application.runServer(); // run server application
   } // end main
} // end class ServerTest
import javax.swing.JFrame;

public class ServerTest
{
   public static void main( String args[] )
   {
      Server application = new Server(); // create server
      application.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
      application.runServer(); // run server application
   } // end main
} // end class ServerTest

Java Syntax (Toggle Plain Text)
import java.io.EOFException;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.InetAddress;
import java.net.Socket;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.JLabel;
 
public class Client extends JFrame 
{
   private JTextField equationField; // enter equation here
   private JTextField answerField;//enter answer here
   private JTextArea displayArea; // display information to user
   private ObjectOutputStream output; // output stream to server
   private ObjectInputStream input; // input stream from server
   private String message = ""; // message from server
   private String chatServer; // host server for this application
   private Socket client; // socket to communicate with server
   private JLabel label;//direction label
 
   // initialize chatServer and set up GUI
   public Client( String host )
   {
      super( "Client" );
 
      chatServer = host; // set server to which this client connects
      /*
      label = new JLabel("Enter equation above and answer below.");//create label
      add (label, BorderLayout.NORTH);
      */
      equationField = new JTextField(); // create enterField
      equationField.setEditable( false );
      equationField.addActionListener(
         new ActionListener() 
         {
            // send message to server
            public void actionPerformed( ActionEvent event )
            {
               sendData( event.getActionCommand() );
               equationField.setText( "" );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener
 
      add( equationField, BorderLayout.NORTH);
 
      answerField = new JTextField(); // create enterField
      answerField.setEditable( false );
      answerField.addActionListener(
         new ActionListener()
         {
            // send message to server
            public void actionPerformed( ActionEvent event )
            {
               sendData( event.getActionCommand() );
               answerField.setText( "" );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener
 
      add( answerField, BorderLayout.SOUTH );
 
      displayArea = new JTextArea(); // create displayArea
      add( new JScrollPane( displayArea ), BorderLayout.CENTER);
 
      setSize( 500, 250 ); // set size of window
      setVisible( true ); // show window
   } // end Client constructor
 
   // connect to server and process messages from server
   public void runClient() 
   {
      try // connect to server, get streams, process connection
      {
         connectToServer(); // create a Socket to make connection
         getStreams(); // get the input and output streams
         processConnection(); // process connection
      } // end try
      catch ( EOFException eofException ) 
      {
         displayMessage( "\nClient terminated connection" );
      } // end catch
      catch ( IOException ioException ) 
      {
         ioException.printStackTrace();
      } // end catch
      finally 
      {
         closeConnection(); // close connection
      } // end finally
   } // end method runClient
 
   // connect to server
   private void connectToServer() throws IOException
   {      
      displayMessage( "Attempting connection\n" );
 
      // create Socket to make connection to server
      client = new Socket( InetAddress.getByName( chatServer ), 12345 );
      displayMessage("Enter equation in top field and answer in the bottom field\n");
      // display connection information
      displayMessage( "Connected to: " + 
         client.getInetAddress().getHostName() );
 
   } // end method connectToServer
 
   // get streams to send and receive data
   private void getStreams() throws IOException
   {
      // set up output stream for objects
      output = new ObjectOutputStream( client.getOutputStream() );      
      output.flush(); // flush output buffer to send header information
 
      // set up input stream for objects
      input = new ObjectInputStream( client.getInputStream() );
 
      displayMessage( "\nGot I/O streams\n" );
   } // end method getStreams
 
   // process connection with server
   private void processConnection() throws IOException
   {
      // enable enterField so client user can send messages
      setTextFieldEditable( true );
 
      do // process messages sent from server
      { 
         try // read message and display it
         {
            message = ( String ) input.readObject(); // read new message
            displayMessage( "\n" + message ); // display message
         } // end try
         catch ( ClassNotFoundException classNotFoundException ) 
         {
            displayMessage( "\nUnknown object type received" );
         } // end catch
 
      } while ( !message.equals( "SERVER>>> TERMINATE" ) );
   } // end method processConnection
 
   // close streams and socket
   private void closeConnection() 
   {
      displayMessage( "\nClosing connection" );
      setTextFieldEditable( false ); // disable enterField
 
      try 
      {
         output.close(); // close output stream
         input.close(); // close input stream
         client.close(); // close socket
      } // end try
      catch ( IOException ioException ) 
      {
         ioException.printStackTrace();
      } // end catch
   } // end method closeConnection
 
   // send message to server
   private void sendData( String message )
   {
      try // send object to server
      {
         output.writeObject( "CLIENT>>> " + message );
         output.flush(); // flush data to output
         displayMessage( "\nCLIENT>>> " + message );
      } // end try
      catch ( IOException ioException )
      {
         displayArea.append( "\nError writing object" );
      } // end catch
   } // end method sendData
 
   // manipulates displayArea in the event-dispatch thread
   private void displayMessage( final String messageToDisplay )
   {
      SwingUtilities.invokeLater(
         new Runnable()
         {
            public void run() // updates displayArea
            {
               displayArea.append( messageToDisplay );
            } // end method run
         }  // end anonymous inner class
      ); // end call to SwingUtilities.invokeLater
   } // end method displayMessage
 
   // manipulates enterField in the event-dispatch thread
   private void setTextFieldEditable( final boolean editable )
   {
      SwingUtilities.invokeLater(
         new Runnable() 
         {
            public void run() // sets enterField's editability
            {
               equationField.setEditable( editable );
               answerField.setEditable(editable);
            } // end method run
         } // end anonymous inner class
      ); // end call to SwingUtilities.invokeLater
   } // end method setTextFieldEditable
} // end class Client
import java.io.EOFException;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.InetAddress;
import java.net.Socket;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.JLabel;

public class Client extends JFrame 
{
   private JTextField equationField; // enter equation here
   private JTextField answerField;//enter answer here
   private JTextArea displayArea; // display information to user
   private ObjectOutputStream output; // output stream to server
   private ObjectInputStream input; // input stream from server
   private String message = ""; // message from server
   private String chatServer; // host server for this application
   private Socket client; // socket to communicate with server
   private JLabel label;//direction label

   // initialize chatServer and set up GUI
   public Client( String host )
   {
      super( "Client" );

      chatServer = host; // set server to which this client connects
      /*
      label = new JLabel("Enter equation above and answer below.");//create label
      add (label, BorderLayout.NORTH);
      */
      equationField = new JTextField(); // create enterField
      equationField.setEditable( false );
      equationField.addActionListener(
         new ActionListener() 
         {
            // send message to server
            public void actionPerformed( ActionEvent event )
            {
               sendData( event.getActionCommand() );
               equationField.setText( "" );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      add( equationField, BorderLayout.NORTH);

      answerField = new JTextField(); // create enterField
      answerField.setEditable( false );
      answerField.addActionListener(
         new ActionListener()
         {
            // send message to server
            public void actionPerformed( ActionEvent event )
            {
               sendData( event.getActionCommand() );
               answerField.setText( "" );
            } // end method actionPerformed
         } // end anonymous inner class
      ); // end call to addActionListener

      add( answerField, BorderLayout.SOUTH );

      displayArea = new JTextArea(); // create displayArea
      add( new JScrollPane( displayArea ), BorderLayout.CENTER);

      setSize( 500, 250 ); // set size of window
      setVisible( true ); // show window
   } // end Client constructor

   // connect to server and process messages from server
   public void runClient() 
   {
      try // connect to server, get streams, process connection
      {
         connectToServer(); // create a Socket to make connection
         getStreams(); // get the input and output streams
         processConnection(); // process connection
      } // end try
      catch ( EOFException eofException ) 
      {
         displayMessage( "\nClient terminated connection" );
      } // end catch
      catch ( IOException ioException ) 
      {
         ioException.printStackTrace();
      } // end catch
      finally 
      {
         closeConnection(); // close connection
      } // end finally
   } // end method runClient

   // connect to server
   private void connectToServer() throws IOException
   {      
      displayMessage( "Attempting connection\n" );

      // create Socket to make connection to server
      client = new Socket( InetAddress.getByName( chatServer ), 12345 );
      displayMessage("Enter equation in top field and answer in the bottom field\n");
      // display connection information
      displayMessage( "Connected to: " + 
         client.getInetAddress().getHostName() );
      
   } // end method connectToServer

   // get streams to send and receive data
   private void getStreams() throws IOException
   {
      // set up output stream for objects
      output = new ObjectOutputStream( client.getOutputStream() );      
      output.flush(); // flush output buffer to send header information

      // set up input stream for objects
      input = new ObjectInputStream( client.getInputStream() );

      displayMessage( "\nGot I/O streams\n" );
   } // end method getStreams

   // process connection with server
   private void processConnection() throws IOException
   {
      // enable enterField so client user can send messages
      setTextFieldEditable( true );

      do // process messages sent from server
      { 
         try // read message and display it
         {
            message = ( String ) input.readObject(); // read new message
            displayMessage( "\n" + message ); // display message
         } // end try
         catch ( ClassNotFoundException classNotFoundException ) 
         {
            displayMessage( "\nUnknown object type received" );
         } // end catch

      } while ( !message.equals( "SERVER>>> TERMINATE" ) );
   } // end method processConnection

   // close streams and socket
   private void closeConnection() 
   {
      displayMessage( "\nClosing connection" );
      setTextFieldEditable( false ); // disable enterField

      try 
      {
         output.close(); // close output stream
         input.close(); // close input stream
         client.close(); // close socket
      } // end try
      catch ( IOException ioException ) 
      {
         ioException.printStackTrace();
      } // end catch
   } // end method closeConnection

   // send message to server
   private void sendData( String message )
   {
      try // send object to server
      {
         output.writeObject( "CLIENT>>> " + message );
         output.flush(); // flush data to output
         displayMessage( "\nCLIENT>>> " + message );
      } // end try
      catch ( IOException ioException )
      {
         displayArea.append( "\nError writing object" );
      } // end catch
   } // end method sendData

   // manipulates displayArea in the event-dispatch thread
   private void displayMessage( final String messageToDisplay )
   {
      SwingUtilities.invokeLater(
         new Runnable()
         {
            public void run() // updates displayArea
            {
               displayArea.append( messageToDisplay );
            } // end method run
         }  // end anonymous inner class
      ); // end call to SwingUtilities.invokeLater
   } // end method displayMessage

   // manipulates enterField in the event-dispatch thread
   private void setTextFieldEditable( final boolean editable )
   {
      SwingUtilities.invokeLater(
         new Runnable() 
         {
            public void run() // sets enterField's editability
            {
               equationField.setEditable( editable );
               answerField.setEditable(editable);
            } // end method run
         } // end anonymous inner class
      ); // end call to SwingUtilities.invokeLater
   } // end method setTextFieldEditable
} // end class Client

Java Syntax (Toggle Plain Text)
import javax.swing.JFrame;
 
public class ClientTest 
{
   public static void main( String args[] )
   {
      Client application; // declare client application
 
      // if no command line args
      if ( args.length == 0 )
         application = new Client( "127.0.0.1" ); // connect to localhost
      else
         application = new Client( args[ 0 ] ); // use args to connect
 
      application.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
      application.runClient(); // run client application
   } // end main
} // end class ClientTest
import javax.swing.JFrame;

public class ClientTest 
{
   public static void main( String args[] )
   {
      Client application; // declare client application

      // if no command line args
      if ( args.length == 0 )
         application = new Client( "127.0.0.1" ); // connect to localhost
      else
         application = new Client( args[ 0 ] ); // use args to connect

      application.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
      application.runClient(); // run client application
   } // end main
} // end class ClientTest

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AllenB

Reputation Points: 10

Solved Threads: 0

Newbie Poster

Offline

13 posts
since Aug 2008

Permalink

Jan 23rd, 2009

Re: Unable to populate String.

Java Syntax (Toggle Plain Text)
private void processConnection() throws IOException {
        String message = "Connection successful";
...
  message = (String) input.readObject(); // read new message
                displayMessage("\n|" + message + "|"); 
                ///"CLIENT>>> " TO REMOVE!
                message = message.substring(10);
...
private void processConnection() throws IOException {
        String message = "Connection successful";
...
  message = (String) input.readObject(); // read new message
                displayMessage("\n|" + message + "|"); 
                ///"CLIENT>>> " TO REMOVE!
                message = message.substring(10);
...

it's all

quuba

Reputation Points: 123

Solved Threads: 106

Posting Pro

Offline

573 posts
since Nov 2008

Permalink

Jan 23rd, 2009

Re: Unable to populate String.

Thank you! That's all I needed.

AllenB

Reputation Points: 10

Solved Threads: 0

Newbie Poster

Offline

13 posts
since Aug 2008

This thread is solved

Either the thread starter or a moderator has marked this thread as solved. You can most likely trust the responses and answers given. There is most likely no reason for any further responses to be posted here. If you have a related question, please start a new thread in this forum instead.

This thread is more than three months old

No one has posted to this discussion for at least three months. Please let old threads die and do not reply to them unless you feel you have something new and valuable to contribute that absolutely must be added to make the discussion complete. Otherwise, please start a new thread in this forum instead.

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