[WEAVER-16] NullPointerException when weaving class with no package

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 2.0
• Component/s: core
• Assignee: Matthew Jason Benson
• Reporter: Bruno P. Kinoshita
• Created: 19/Nov/16 06:06
• Updated: 07/Sep/18 19:34
• Resolved: 02/Aug/18 23:12

Description

This issue happened while quickly writing an example with weaver to test another issue.

I created a sample project to call the maven-plugin with privilizer, as in the project home page example.

import org.apache.commons.weaver.privilizer.Privileged;

public class SimpleClass {

    public void sayA() {
        System.out.println("Aaa");
    }
    
    @Privileged
    public void sayNothing() {
        System.out.println("Nothing");
    }
}

As I was in a hurry, I didn't bother creating a package, adding comments, etc. When I asked Eclipse to build the project, it threw a NPE. Then I tried via command line, same behavior.

My pom.xml was using version 1.3, but since I have the project sources in my workspace, I re-synced the local repo, `mvn install`'d, and then updated the pom to use 1.4-SNAPSHOT.

Same issue. I believe the issue is in the ScanResult#getWeavable method that returns a WeavablePackage.

// snip
    /**
     * Public for use by {@link WeaveProcessor}.
     * @param pkg to wrap
     * @return {@link WeavablePackage}
     */
    public WeavablePackage getWeavable(final Package pkg) {
        final String key = pkg.getName();
        if (packages.containsKey(key)) {
            return packages.get(key);
        }
        final WeavablePackage result = new WeavablePackage(pkg);
        final WeavablePackage faster = packages.putIfAbsent(key, result);
        return faster == null ? result : faster;
    }
// snip

I believe when you create a class with no package, trying to get its package (i.e. obj.getClass().getPackage()) will return null. So I'm no sure how this issue could be fixed. Simply passing a null to WeavablePackage's contructor seems like will create other issues...

For the time being, will update my example to use packages.