[MNG-6932] NullPointerException if no Package is defined for the current class

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 3.6.3
• Fix Version/s: 4.0.x-candidate
• Component/s: POM
• Environment: Windows 10, Java 8, custom classloading
• Assignee: Unassigned
• Reporter: Bence Sipka
• Created: 05/Oct/19 15:26
• Updated: 27/Nov/20 12:38

Description

When the maven-resolver and related classes are used with a ClassLoader that doesn't define a java.lang.Package object for the loaded classes, the library throws a NullPointerException.

Scenario: I'm using the maven-resolver classes to resolver artifacts from various repositories. I package the app, and deploy it to a custom environment where the ClassLoader for the app doesn't define a Package for the loaded classes. In these cases, when the maven-resolver library calls this.getClass().getPackage().getImplementationVersion() then a NullPointerException will occurr.

 The following classes are affected:
DefaultSuperPomProvider.getSuperModel():81
DefaultReportingConverter.<init>:56

Code around the locations:

String modelId = "org.apache.maven:maven-model-builder:"
    + this.getClass().getPackage().getImplementationVersion() + ":super-pom";
InputSource inputSource = new InputSource();
inputSource.setModelId( modelId );

This exception makes the library unportable to different environments.

Workaround:

Implement a custom variant of the above classes that circumvent these parts of the code.

Possible solution:

Null checks, and hard coding the version number.

Issue Links

• depends upon: MNG-6960 Use RuntimeInformation instead of reading properties
• is caused by: MNG-6593 track input location for super-pom
• is caused by: MNG-6600 add input location tracking for default lifecycle bindings executions