Execution order of Enum in java

Question

I got a question about Enum.

I have an enum class looks like below

public enum FontStyle {
    NORMAL(\"This font has normal style.\"),
    BOLD(\"T         


        

Answer 1

Yes, enums are static constants but are not compile time constants. Just like any other classes enum is loaded when first time needed. You can observe it easily if you change its constructor a little

FontStyle(String description) {
    System.out.println("creating instace of "+this);// add this
    this.description = description;
}

and use simple test code like

class Main {
    public static void main(String[] Args) throws Exception {
        System.out.println("before enum");
        FontStyle style1 = FontStyle.BOLD;
        FontStyle style2 = FontStyle.ITALIC;
    }
}

If you will run main method you will see output

before enum
creating instace of NORMAL
creating instace of BOLD
creating instace of ITALIC
creating instace of UNDERLINE

which shows that enum class was loaded (and its static fields have been initialized) right when we wanted to use enum first time.

You can also use

Class.forName("full.packag.name.of.FontStyle");

to cause its load if it wasn't loaded yet.