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Thread: linking of classes

  1. #1
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    Default linking of classes

     
    I am new to this forum,please pardon my mistakes.I want to link these two java classes together.here are my codes.

    AustasMain.java(A)

    import java.awt.event.ActionListener.*;
    import java.awt.event.ActionEvent;
    import java.awt.*; 
    import java.awt.event.*;
    import java.awt.Label.*;
    import javax.swing.*;
    import java.awt.Graphics;
    import java.awt.Graphics2D;
    import java.sql.*;
    public class AustasMain extends JPanel {
    String user;
    double pass;
    double pass1=1234;
    String userr="user";
    Label username,password;
    TextField username1,password1;
    private JButton ok;
    private JTextArea textarea;
    private SecMain sec; 
    public AustasMain () {
    setLayout(new FlowLayout());
    username=new Label("USERNAME");add(username);
    username1= new TextField(10);add(username1);
    password=new Label("PASSWORD");add(password);
    password1=new TextField(10);add(password1);
    ok=new JButton("OK");add(ok);
     
     
    TextHandler handler=new TextHandler();
    username1.addActionListener(handler);
    password1.addActionListener(handler);
    ok.addActionListener(handler);
    }
     
    class TextHandler implements ActionListener {
    public void actionPerformed(ActionEvent event) { 
    if(event.getSource()==username1){
    String user=(username1.getText());
             }
    if(event.getSource()==password1){
    double pass=Double.parseDouble(password1.getText());
             }
    if(event.getSource()==ok) {
    String user=(username1.getText()); 
    int pars=Integer.parseInt(password1.getText());
    String pass=(password1.getText());
    double pass1=1234;
    String userr="user";
    try{
    		 if(user.equals("") && pass.equals("")) {
          JOptionPane.showMessageDialog(null,"Enter login name or password","Error",JOptionPane.ERROR_MESSAGE);
      }
    		else if (user.equals("user") && pass.equals("400")) {
        // this calls the class below.here A passes to B.
         SecsMain sec=new SecsMain();
        sec.pas=pars;
        sec.setVisible(true);
        				}
    		else {
         JOptionPane.showMessageDialog(null,"Invalid login name or password","Error",JOptionPane.ERROR_MESSAGE);
         username1.setText("");
         password1.setText("");
      				}
       }
        catch(Exception e){}                    
    }
    }
    }
    public static void main(String [] args) {
    AustasMain panel=new AustasMain();
    JFrame frame=new JFrame("LOGIN FORM");
    frame.setSize(250,200);
    frame.add(panel);
    frame.setVisible(true);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
                                      }

    the second class is :
    Secs.java(B)

    import java.awt.*;           //
    import java.awt.event.*;    //  PACKAGES
    import javax.swing.*;      //
    import java.sql.*;        //
    import java.awt.event.ActionListener.*;
    import java.awt.event.ActionEvent;
     
     
    public class SecsMain extends JFrame implements ActionListener {
           private JButton mkt,acct,store;int pas;
           //-----Constructor------
     
           public SecsMain() {
                  super("DEPARTMENTS");              
                  setLayout(new GridLayout(1,4));
                  mkt = new JButton("MARKET");
                  mkt.setPreferredSize(new Dimension(150,300));
                  mkt.setSize(mkt.getPreferredSize());              
                  mkt.addActionListener(this);
                  add(mkt);
                  acct = new JButton("ACCOUNT");
                  acct.setPreferredSize(new Dimension(150,300));
                  acct.setSize(acct.getPreferredSize());
                  acct.addActionListener(this);
                  add(acct);
                  JButton store= new JButton ("STORE");
                  store.setPreferredSize(new Dimension(150,300));
                  store.setSize(store.getPreferredSize());
                  add(store);
                  JButton md= new JButton ("MD");
                  md.setPreferredSize(new Dimension(150,300));
                  md.setSize(md.getPreferredSize());
                  add(md);
                  setSize(pas,300);              
    				} 
    public void actionPerformed(ActionEvent event) { }
    }
    //The program compiles but does not call the second program when the username and password is correctly entered.Please help me.
    Last edited by henryjavaprofor; May 3rd, 2012 at 08:21 AM.


  2. #2
    Crazy Cat Lady KevinWorkman's Avatar
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    Default Re: linking of classes

    I moved this thread from the tutorial forum as this is not a tutorial. Also, please use the highlight tags to preserve formatting when you post code.

    What exactly do you mean by "linking of classes"? You're going to have to make an instance of each, then provide a reference in one class to the other instance. How you should do that depends on how these classes are related.
    Useful links: How to Ask Questions the Smart Way | Use Code Tags | Java Tutorials
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  3. #3
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    Default Re: linking of classes

    Thanks for your help but i am writing a program where the first interface being the login frame will get the username and the password and then pass it on to the second interface where it will open a second frame.i want to know how i can pass for instance what class A gets unto class B.

  4. #4
    Super Moderator Norm's Avatar
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    Default Re: linking of classes

    class A would need a reference to an instance of class B. Given that, the code in class A can call methods in class B to pass it data.
    If you don't understand my answer, don't ignore it, ask a question.

  5. #5
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    Default Re: linking of classes

    thanks.check my codes i did reference it.Didn't i do it well?

  6. #6
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    Default Re: linking of classes

    Please Edit your post and wrap your code with[code=java]<YOUR CODE HERE>[/code] to get highlighting. Unformatted code is hard to read and understand.

    Which is class A and which is class B? Where are you trying to pass what class A gets unto class B.
    If you don't understand my answer, don't ignore it, ask a question.

  7. #7
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    Default Re: linking of classes

    thanks i have done it

  8. #8
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    Default Re: linking of classes

    please help me.do not leave at this point

  9. #9
    Super Moderator Norm's Avatar
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    Default Re: linking of classes

    Please explain what the problem is now.
    If you don't understand my answer, don't ignore it, ask a question.

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