Bug 334315

Summary:

[compiler] Problem types with missing superclass or superinterfaces should use Object for missing types

Product:

[Eclipse Project] JDT

Reporter:

Olivier Thomann <Olivier_Thomann>

Component:

Core

Assignee:

Olivier Thomann <Olivier_Thomann>

Status:

VERIFIED FIXED

QA Contact:

Severity:

normal

Priority:

CC:

aniefer, jarthana

Version:

3.7

Target Milestone:

3.7 M5

Hardware:

OS:

Windows 7

Whiteboard:

Attachments:

Description	Flags
Proposed fix + updated regression test	none

Description Olivier Thomann

2011-01-13 15:20:52 EST

When a type has a missing type binding for its superclass, it should dump java.lang.Object for the superclass, otherwise the class will never be able to load.
The user will get a java.lang.NoClassDefFoundError.
The problem occurred for Andrew who was debugging some code where the ant task superclass was missing. This prevents the problem method to be called and help the user to find out that the code didn't compile.

Comment 1 Olivier Thomann

2011-01-13 15:25:59 EST

For example:
public class X extends Zork {
	public static void main(String[] args) {
	}
}

Would lead to this error at runtime:

Exception in thread "main" java.lang.NoClassDefFoundError: Zork
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClassCond(ClassLoader.java:632)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:616)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
        at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
Caused by: java.lang.ClassNotFoundException: Zork
        at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
        ... 12 more
Could not find the main class: X.  Program will exit.

instead of:
Exception in thread "main" java.lang.Error: Unresolved compilation problem:

        at X.main(X.java:2)

This is not much helpful as is, but at least it shows that the type didn't compile properly instead of indicating a class loader/resolution issue.

Comment 2 Olivier Thomann

2011-01-14 10:33:21 EST

Created attachment 186829 [details]
Proposed fix + updated regression test

Comment 3 Olivier Thomann

2011-01-14 10:33:49 EST

Released for 3.7M5.

Comment 4 Jay Arthanareeswaran

2011-01-25 04:54:23 EST

Verified for 3.7M5 using build I20110124-1800.