Is usage of anonymous classes in Java considered bad style or good?

Question

I know anonymous classes save typing when it comes to implementing Listener and similar stuff. They try to be a replacement for some usages of closures.

But what doe

Answer 1

One more good use of anonymous inner class is when you need to initialize collections like ArrayList and Set. This practice is also known as double brace initialization For example ,

private static final Set VALID_CODES = new HashSet() {{
add("XZ13s");
add("AB21/X");
add("YYLEX");
add("AR2D");
}};

Obviously, this is not limited to collections; it can be used to initialize any kind of object -- for example Gui objects:

 add(new JPanel() {{
setLayout(...);
setBorder(...);
add(new JLabel(...));
add(new JSpinner(...));
}});