Hi,
I am wondering if someone may be able to point me in the right direction
here... after reviewing the J2SE spec, and the Servlet 2.4 Spec, its not
too clear whether circular dependecies such as the one I am investigating
below are legal or supported by Tomcat. Sun J2SE 5.0 classloader does not
seem to support such initialization although the Tomcat classloader (v5.5)
seems to an operation such as my example below.
An exert of the Java specification states:
12.4.2, #3 If initialization is in progress for the class or interface by
the current thread, then this must be a recursive request for
initialization. Release the lock on the Class object and complete normally.
Servlet 2.4 spec says that Classloaders need to follow the J2SE
specification.
So as I am investigating the Tomcat 5.5 classloader I am wondering if either
one of these situations are legal for Tomcat 5.5 or whether I should be
observing a ClassCircularityError... debugging my App shows the following
behavior:
Examples :
Class A {
static {
System.out.println(B.somefield); // debugger shows that A is checked and the
static block is invoked. B is loaded which initializes B.somefield through
the constructor of A.
}
}
Class B {
public static final A somefield;
}
and/or circular dependecy from Parent static initializers
Class Parent {
static {
System.out.println(B.somefield); // debugger shows A is checked, Parent is
loaded which loads B which loads somefield through the constructor of class
"A"
}
}
Class A extends Parent {
}
Class B {
public static final A somefield;
}
Thanks in advance.
Best Regards,
Mich
