Error in adding radio buttons in a button group in Swing

Question

I want to covert my code in AWT to Swing in Java.

 ButtonGroup group1=new ButtonGroup();
JRadioButton radio1=new JRadioButton("Brute Force Technique",true);
JRadioButton radio2=new JRadioButton("Simulated Annealing Technique",false);
     //ButtonGroup group1 = new ButtonGroup();
     group1.add( radio1 );
group1.add(radio2);

But these lines are showing errors.

group1.add(radio1); 
and group1.add(radio2) ;

The error is:

error:package group1 does not exist <identifier> expected

I am working in Netbeans IDE 7.1.2. I am new to Java. Can anyone please suggest what is the problem in my code?

My complete code which was written in AWT & I'm converting it to Swing is here: travellingsalesmanproblem.java.

Answer 1

Create a method... and inside that do this... or Surround the "add" with {}

eg:

     ButtonGroup group1=new ButtonGroup();
     JRadioButton radio1=new JRadioButton("Brute Force Technique",true);
     JRadioButton radio2=new JRadioButton("Simulated Annealing Technique",false);

    public void go()
{

     group1.add( radio1 );
     group1.add(radio2);

}

OR

     ButtonGroup group1=new ButtonGroup();
     JRadioButton radio1=new JRadioButton("Brute Force Technique",true);
     JRadioButton radio2=new JRadioButton("Simulated Annealing Technique",false);

     {

            group1.add( radio1 );
            group1.add(radio2);
     }

Answer 2

Operations like that should be invoked in block not in class field declaration section. Maybe move it to constructor or surround it by { } like

public class TravellingSalesmanProblem extends JApplet implements ActionListener {
    ...

    ButtonGroup group1 = new ButtonGroup();
    JRadioButton radio1Button=new JRadioButton("Brute Force Technique",true);
    JRadioButton radio2Button=new JRadioButton("Simulated Annealing Technique",false);
    {
        group1.add(radio1Button);
        group1.add(radio2Button);
    }