In java, what does this type of class compile?


Below is the code that defines class type:

package annotationtype;

public class Example {

    public static void main(String[] args){


that gets functionally compiled by javac to:

public class annotationtype.Example{
    public static Class<annotationtype.Example> class;
        class = Class.forName("annotationtype.Example")
    public annotationtype.Example(){}
    public static void main(java.lang.String[] args){}

My major focus is on the Class<annotationtype.Example> class static member variable in the above code. In addition, this member variable Class<annotationtype.Example> class is actually pointing to an object of type class Class that maintains meta data of class Example after class Example gets loaded into memory.

Is my understanding correct?

Class literals are part of the language specification as noted in JLS 15.8.2

A class literal is an expression consisting of the name of a class, interface, array, or primitive type, or the pseudo-type void, followed by a '.' and the token class.

The type of C.class, where C is the name of a class, interface, or array type (§4.3), is Class<C>.

The type of p.class, where p is the name of a primitive type (§4.2), is Class<B>, where B is the type of an expression of type p after boxing conversion (§5.1.7).

The type of void.class (§8.4.5) is Class<Void>.

javac doesn't create a static class field for each class, but it will recognize a class literal expression and compile it correctly.

Take for example the class:

public class Hello {
        public static void main(String[] args){
                Class<?> myClass = Hello.class;
                System.out.println("Hello, " + myClass);

This compiles to (only relevant sections of bytecode included):

public class Hello   minor version: 0   major version: 52   flags:
Constant pool:
#1 = Methodref          #11.#20        // java/lang/Object."<init>":()V
#2 = Class              #21            // Hello
public static void main(java.lang.String[]);
descriptor: ([Ljava/lang/String;)V
  stack=3, locals=2, args_size=1
     0: ldc           #2                  // class Hello
     2: astore_1

You can see that javac has put a reference to the Hello class in the constant pool and then loaded that constant when I refer to it in main.