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.