[HARMONY-5005] [drlvm][kernel][geronimo] Field.getGenericType() fails on a parametrized class from custom classloader

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Component/s: App-Oriented Bug Reports, DRLVM
• Patch Info: Patch Available
• Assignee: Gregory Shimansky
• Reporter: Vasily Zakharov
• Created: 23/Oct/07 03:40
• Updated: 20/Mar/08 14:35
• Resolved: 01/Nov/07 15:22

Description

java.lang.reflect.Field.getGenericType() fails if the field it's called upon is a parametrized class unavailable through the system class loader. To reproduce use the following code:

import java.lang.reflect.*;
import java.net.*;
public class Test {
public static void main(String[] args) {
try {
ClassLoader loader = new URLClassLoader(new URL[]

{ new URL("file:foo.jar") }

);
Class cls = loader.loadClass("Foo");
Field field = cls.getDeclaredField("field");
Type type = field.getGenericType();
System.out.println("SUCCESS: " + type);
} catch (Exception e)

{ e.printStackTrace(System.out); }

}
}
class Foo {
java.util.List<Foo> field;
}

After compilation create a foo.jar containing Foo.class and then make sure to remove Foo.class file:

$ jar cvf foo.jar Foo.class
$ rm Foo.class
$ java Test

Output on RI:

SUCCESS: java.util.List<Foo>

Output on Harmony:

java.lang.TypeNotPresentException: Type Foo not present
at org.apache.harmony.lang.reflect.support.AuxiliaryCreator.createTypeArgs(AuxiliaryCreator.java:216)
at org.apache.harmony.lang.reflect.parser.Parser.parseFieldGenericType(Parser.java:358)
at java.lang.reflect.Field.getGenericType(Field.java:72)
at Test.main(Test.java:9)
Caused by: java.lang.ClassNotFoundException: Foo
at org.apache.harmony.lang.reflect.support.AuxiliaryLoader.findClass(AuxiliaryLoader.java:119)
at org.apache.harmony.lang.reflect.support.AuxiliaryCreator.createTypeArg(AuxiliaryCreator.java:192)
at org.apache.harmony.lang.reflect.support.AuxiliaryCreator.createTypeArgs(AuxiliaryCreator.java:214)
at org.apache.harmony.lang.reflect.parser.Parser.parseFieldGenericType(Parser.java:358)
... 2 more

My guess is the problem lies in AuxiliaryLoader.findClass() method, line 67 - the method explicitly uses system class loader to load the target class, which clearly fails if the target class is available through some other classloader. It seems logical to use the classloader of the class whose field is being processed instead. However, the fix seems non-trivial as in the existing architecture the information on the containing class is lost when Parser is called.

This issue prevents Apache Geronimo 2.0 from starting on Harmony.

Issue Links

• relates to: HARMONY-5086 [drlvm][kernel][geronimo] AnnotatedElement.getDeclaredAnnotations() throws exception if annotation is not available
• relates to: HARMONY-5622 [drlvm][kernel][geronimo] Method.getGeneric*() methods throw NPE for parametrized interface methods