JCheckBox issue in Java?

Question

This is my code here in this i want to get output as following but some error is there

---Outputs----

Name Arun.Gender Male. He likes nothing.

Name Arun.Gender Male. He likes Cricket only

Name Arun.Gender Male. He likes Cricket and Tennis.

Name Arun.Gender Male. He likes Cricket ,Football and Tennis

/*
 * Register.java
 *
 * Created on 8 October, 2014, 9:27 AM
 */

package Register;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

/**
 *
 * @author  DELL
 */
public class Register extends javax.swing.JFrame {

    /** Creates new form Register */
    public Register() {
    initComponents();
    initListener() ;
    }

    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">
    private void initComponents() {

    bg = new javax.swing.ButtonGroup();
    buttonGroup2 = new javax.swing.ButtonGroup();
    jPanel1 = new javax.swing.JPanel();
    rb_female = new javax.swing.JRadioButton();
    cb_cricket = new javax.swing.JCheckBox();
    txt_name = new javax.swing.JTextField();
    lbl_name = new javax.swing.JLabel();
    cb_tennis = new javax.swing.JCheckBox();
    jScrollPane1 = new javax.swing.JScrollPane();
    ta_show = new javax.swing.JTextArea();
    rb_male = new javax.swing.JRadioButton();
    cb_football = new javax.swing.JCheckBox();
    btn_show = new javax.swing.JButton();
    lbl_hobbies = new javax.swing.JLabel();
    lbl_gender = new javax.swing.JLabel();

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

    jPanel1.setBorder(javax.swing.BorderFactory.createTitledBorder(null, "Register", javax.swing.border.TitledBorder.DEFAULT_JUSTIFICATION, javax.swing.border.TitledBorder.DEFAULT_POSITION, new java.awt.Font("Times New Roman", 1, 14))); // NOI18N

    bg.add(rb_female);
    rb_female.setFont(new java.awt.Font("Times New Roman", 1, 14));
    rb_female.setText("Female");

    cb_cricket.setFont(new java.awt.Font("Times New Roman", 1, 14));
    cb_cricket.setText("Cricket");

    lbl_name.setFont(new java.awt.Font("Times New Roman", 1, 14));
    lbl_name.setText("Name");

    cb_tennis.setFont(new java.awt.Font("Times New Roman", 1, 14));
    cb_tennis.setText("Tennis");

    ta_show.setColumns(20);
    ta_show.setRows(5);
    jScrollPane1.setViewportView(ta_show);

    bg.add(rb_male);
    rb_male.setFont(new java.awt.Font("Times New Roman", 1, 14));
    rb_male.setText("Male");

    cb_football.setFont(new java.awt.Font("Times New Roman", 1, 14));
    cb_football.setText("Football");

    btn_show.setFont(new java.awt.Font("Times New Roman", 1, 14)); // NOI18N
    btn_show.setText("Show");

    lbl_hobbies.setFont(new java.awt.Font("Times New Roman", 1, 14));
    lbl_hobbies.setText("Hobbies");

    lbl_gender.setFont(new java.awt.Font("Times New Roman", 1, 14));
    lbl_gender.setText("Gender");

    javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
    jPanel1.setLayout(jPanel1Layout);
    jPanel1Layout.setHorizontalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(jPanel1Layout.createSequentialGroup()
        .addContainerGap()
        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(lbl_gender)
            .addComponent(lbl_name)
            .addComponent(lbl_hobbies)
            .addComponent(btn_show))
        .addGap(30, 30, 30)
        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
            .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addComponent(cb_cricket)
                .addComponent(cb_football)
                .addComponent(cb_tennis))
            .addGap(103, 103, 103))
            .addGroup(jPanel1Layout.createSequentialGroup()
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(rb_male)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(rb_female))
            .addComponent(txt_name, javax.swing.GroupLayout.DEFAULT_SIZE, 277, Short.MAX_VALUE)
            .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 277, javax.swing.GroupLayout.PREFERRED_SIZE))
        .addContainerGap())
    );
    jPanel1Layout.setVerticalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(jPanel1Layout.createSequentialGroup()
        .addContainerGap()
        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
            .addComponent(lbl_name)
            .addComponent(txt_name, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
        .addGap(32, 32, 32)
        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
            .addComponent(lbl_gender)
            .addComponent(rb_female)
            .addComponent(rb_male))
        .addGap(35, 35, 35)
        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
            .addComponent(lbl_hobbies)
            .addComponent(cb_cricket))
        .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jPanel1Layout.createSequentialGroup()
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(cb_football)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(cb_tennis)
            .addGap(18, 18, 18)
            .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addGroup(jPanel1Layout.createSequentialGroup()
            .addGap(105, 105, 105)
            .addComponent(btn_show)))
        .addContainerGap())
    );

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
        .addGap(38, 38, 38)
        .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
        .addGap(57, 57, 57))
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
        .addGap(19, 19, 19)
        .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
        .addGap(23, 23, 23))
    );

    pack();
    }// </editor-fold>

    public void initListener() 
    {
    ActionListener al=new ActionListener() 
    {

        String name;
        String gender;  
        String hobbies[] = new String[10];            


        String data1;
        String data2;
        String data3;
        int i=-1;
        String show;


        public void actionPerformed(ActionEvent e) 
        {
        name = txt_name.getText();

        data1="Name is "+name+". ";

        //*************************************

        if (rb_male.isSelected()) 
        {
            gender = "Male";

        } 
        else if (rb_female.isSelected()) 
        {
            gender = "Female";
        }


        data2="Gender  "+gender+". ";


         if(gender.equals("Male"))
        {
            data3="He likes ";
        }
        else 
        {
            data3="She likes ";
        }




        //*************************************

        String b = "";

        if (cb_cricket.isSelected()) 
        {
            hobbies[i++] = "Cricket";

        }
        if (cb_football.isSelected()) 
        {
            hobbies[i++] = "Football";

        }
        if (cb_tennis.isSelected()) 
        {
            hobbies[i++] = "Tennis";

        }
        System.out.println("iSelected= " + i);

        if (i == -1) 
        {
            b = " nothing";
        } 
        else 
        {
            for (int j = 0; j < i; j++) 
            {

            if (i > 0) 
            {
                if (j < i - 2) 
                {
                b = b + hobbies[j] + ", ";
                } 
                else if (j == i - 2) 
                {
                b = b + hobbies[j] + " and ";
                } 
                else 
                {
                b = b + hobbies[j] + ".";
                }
            } 
            else if (i == 0) 
            {

                b = b + hobbies[j] + " only";

            }
            }
        }
        show=data1+data2+data3+b;
        ta_show.setText(show);


        //************************************* 







        //*************************************
          // ta_show.setText(data1+data2+b);
        }



    };
    btn_show.addActionListener(al);
    }



    /**
    * @param args the command line arguments
    */
    public static void main(String args[]) {
    java.awt.EventQueue.invokeLater(new Runnable() {
        public void run() {
        new Register().setVisible(true);
        }
    });
    }

    // Variables declaration - do not modify
    private javax.swing.ButtonGroup bg;
    private javax.swing.JButton btn_show;
    private javax.swing.ButtonGroup buttonGroup2;
    private javax.swing.JCheckBox cb_cricket;
    private javax.swing.JCheckBox cb_football;
    private javax.swing.JCheckBox cb_tennis;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JLabel lbl_gender;
    private javax.swing.JLabel lbl_hobbies;
    private javax.swing.JLabel lbl_name;
    private javax.swing.JRadioButton rb_female;
    private javax.swing.JRadioButton rb_male;
    private javax.swing.JTextArea ta_show;
    private javax.swing.JTextField txt_name;
    // End of variables declaration

}

the mistake part of this code is

        String b = "";

        if (cb_cricket.isSelected()) 
        {
            hobbies[i++] = "Cricket";

        }
        if (cb_football.isSelected()) 
        {
            hobbies[i++] = "Football";

        }
        if (cb_tennis.isSelected()) 
        {
            hobbies[i++] = "Tennis";

        }
        System.out.println("iSelected= " + i);

        if (i == -1) 
        {
            b = " nothing";
        } 
        else 
        {
            for (int j = 0; j < i; j++) 
            {

            if (i > 0) 
            {
                if (j < i - 2) 
                {
                b = b + hobbies[j] + ", ";
                } 
                else if (j == i - 2) 
                {
                b = b + hobbies[j] + " and ";
                } 
                else 
                {
                b = b + hobbies[j] + ".";
                }
            } 
            else if (i == 0) 
            {

                b = b + hobbies[j] + " only";

            }
            }
        }
        show=data1+data2+data3+b;
        ta_show.setText(show);

Yeah, elaborate on what the error is. And some information about what you're trying to achieve would be very helpful. Currently this is a giant code dump, which will garner little to no responses. — Dan Temple, Oct 22 '14 at 06:48
@SymonKt it is better to explain what 'some error' is, instead of asking other to run the code. Primarily because it's rude (we're not paid for answering questions), but also it is possible that people aren't in front of their working/development machine. Please see [How to create a Minimal, Complete, and Verifiable example](http://stackoverflow.com/help/mcve). — Sufian, Aug 22 '17 at 11:42

score 0 · Answer 1 · answered Oct 22 '14 at 07:06

There are more problems than (I assume you meant) ArrayIndexOutOfBounds. If it is this case, try using

hobbies[++i] = "Cricket"; hobbies[++i] = "Football"; hobbies[++i] = "Tennis";

instead of i++. You initialize variable i with value -1 When using i++, the value of i is incremented after the command was executed. If you use ++i, the value is incremented before the command execution.

And as I mentioned earlier, there are more problems than this one. Not runtime errors, but you won't get desired output yet, even after this change (++i).

Yes Sir correct but using this as above if cricket is selected onece and deselected again selected cricket that i value is increment — Symon Kt, Oct 22 '14 at 07:52

Dawnkeeper · Accepted Answer · 2014-10-22T08:03:44.360

There are multiple problems there.

Firstly one of the genders should be pre-selected. You get an NullPointerException if none is.

And for the ArrayIndexOutOfBoundsException I propose using a list:

LinkedList<String> hobbies = new LinkedList<String>(); 

//...

 hobbies.clear();

    if (cb_cricket.isSelected()) 
    {
        hobbies.add("Cricket");

    }
    if (cb_football.isSelected()) 
    {
        hobbies.add("Football");

    }
    if (cb_tennis.isSelected()) 
    {
        hobbies.add("Tennis");

    }

    if (hobbies.size() == 0) 
    {
        b = " nothing";
    } 
    else 
    {
        for (int j = 0; j < hobbies.size(); j++) 
        {
            if( j > 0)
            {
                if(j == hobbies.size()-1)
                {
                    b += " and ";
                }
                else
                {
                    b += ", ";
                }
            }

            b+= hobbies.get(j);
        } 

        if (hobbies.size() == 1) 
        {

            b += " only";

        }

        b += ".";

    }

Using a LinkedList you get a better scaleable result.

Bonus Points for replacing b with a StringBuilder.

@SymonKt you mean the missing ',' in the hobby list: I corrected that. But this site is not here to write the code for you. — Dawnkeeper, Oct 22 '14 at 08:06
@SymonKt If the answer did help you it would be nice if you accepted it. — Dawnkeeper, Oct 22 '14 at 08:46

JCheckBox issue in Java?

2 Answers2