JRadioButton setMnemonic broken Java 1.5

Question

I am attempting to convert a short JComboBox to a JRadioButton group. When defining the radio buttons, it is telling me it doesn't like my setMnemonic syntax.

My code:

public JRadioButton mailRadio = new JRadioButton("Mail");
mailRadio.setMnemonic(KeyEvent.VK_M);

It will show setMnemonic(int) in intellisense (or whatever the java version is called), but as soon as I accept that, mailRadio.setMnemonic is underlined for a syntax error. Hovering over it gives the error "Type mailRadio.setMnemonic not found." Compiling gives the error "Invalid method declaration; return type required."

As far as I know, I am attempting to do neither of these things. I haven't used Java in a long time, and I'm very rusty. I don't know what I'm doing wrong.

I have three JRadioButtons like this, and it will only show the error on the first one, until I comment it or remove then, then the error moves down to the next.

I am using JDeveloper 10.1.3.5, Java 1.5.0_06. Upgrading either is not an option at the moment, unfortunately.

Answer 1

Seeing that you used public to declare the variable, I'm assuming the code snippet is inside a class declaration.

You can't use statements (and a method call such as setMnemonic is a statement) in a class declaration. You should call this method inside a constructor :

public class XXX {
    public JRadioButton mailRadio = new JRadioButton("Mail");

    public XXX() {
        mailRadio.setMnemonic(KeyEvent.VK_M);
    }       
}

An alternative that looks more like what you initially tried to do is an initializer block:

public class XXX {
    public JRadioButton mailRadio = new JRadioButton("Mail");

    {
        mailRadio.setMnemonic(KeyEvent.VK_M);
    }
}

But this is bad practice, I'm only mentioning it for completeness' sake.

More details in the doc.