JVM treats non-static <clinit> as class initialization method

Name: vsR10008 Date: 05/30/2000




JVMS 2nd ed. (CHAPTER 3 "The Structure of the Java Virtual Machine", section 3.9
"Specially Named Initialization Methods") reads:

"A class or interface has at most one class or interface initialization method.
...
The initialization method of a class or interface is static and takes no arguments.
It has the special name <clinit>"

The following test shows that JVM implicitly invokes non-static <clinit> treating it
as class initialization method.

------------------------------------------------------------------ c.jasm -----

super public class c
{

public static Field a:I;

public Method "<init>":"()V"
stack 1 locals 1
{
aload_0;
invokespecial Method java/lang/Object."<init>":"()V";
return;
}

Method "<clinit>":"()V"
stack 1 locals 1
{
iconst_1;
putstatic Field a:"I";
return;
}

}

------------------------------------------------------------------ t.java -----

public class t {
    public static void main(String[] argv) {
        try {
            if ( c.a == 0 ) {
                System.out.println("PASSED!");
                System.exit(0);
            } else {
                System.out.println("FAILED, a=" +c.a);
            }
        } catch (Throwable t) {
            System.out.println("FAILED: Exception "+t);
        }
    }
}

--------------------------------------------------------------------------------

$ java -version
java version "1.3.0rc3"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.0rc3-Z)
Java HotSpot(TM) Client VM (build 1.3.0rc3-Z, interpreted mode)

$ uname -a
SunOS novo12 5.7 Generic_Patch sun4u sparc SUNW,Ultra-2

$ jasm c.jasm

$ javac -d . t.java

$ java t

FAILED, a=1

This bug is reproduced in all available builds of JDK (1.0-1.4beta)
and affects Classic and HotSpot both.

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