I m trying to make a jcombobox that has 3 colors red, yellow and green.........its a run time error.......caus i m not getting the required output

Question

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package Exp4;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JComboBox;
import javax.swing.JFrame;
* @author Gursimran
public class combox extends JFrame implements ItemListener{
    public combox()
        JComboBox cb;
        setLayout(new GridLayout(10,10));
        cb= new JComboBox<>();
        cb.addItem("Red");
        cb.addItem("Green");
        cb.addItem("Blue");
        add(cb);
        cb.addItemListener(this);
        setVisible(true);
        setSize(400,400);
    public static void main(String[] args)
        combox obj=new combox();
    @Override
    public void itemStateChanged(ItemEvent e)
        if(e.getItemSelectable().equals(0))
                    this.getContentPane().setBackground(Color.red);
        else if(e.getItemSelectable().equals(1))
                    this.getContentPane().setBackground(Color.green);

Answer 1

Please post the exact error message you get.