Trying to diagnose an NPE associated with cloudbees-template.

In 1.516:
java.lang.NullPointerException
	at hudson.maven.ModuleName.equals(ModuleName.java:115)
	at hudson.maven.MavenModuleSet.reconfigure(MavenModuleSet.java:1108)
	at hudson.maven.MavenModuleSetBuild$MavenModuleSetBuildExecution.parsePoms(MavenModuleSetBuild.java:907)
	at hudson.maven.MavenModuleSetBuild$MavenModuleSetBuildExecution.doRun(MavenModuleSetBuild.java:631)

maven-plugin/src/main/java/hudson/maven/ModuleName.java

@@ -31,6 +31,7 @@ import org.apache.maven.model.Dependency;
 import org.apache.maven.model.ReportPlugin;
 
 import java.io.Serializable;
+import javax.annotation.Nonnull;
 
 /**
  * Version independent name of a Maven project. GroupID+artifactId.
@@ -39,10 +40,16 @@ import java.io.Serializable;
  * @see ModuleDependency
  */
 public class ModuleName implements Comparable<ModuleName>, Serializable {
-    public final String groupId;
-    public final String artifactId;
+    public final @Nonnull String groupId;
+    public final @Nonnull String artifactId;
 
     public ModuleName(String groupId, String artifactId) {
+        if (groupId == null) {
+            throw new NullPointerException("Must specify groupId");
+        }
+        if (artifactId == null) {
+            throw new NullPointerException("Must specify artifactId");
+        }
         this.groupId = groupId;
         this.artifactId = artifactId;
     }

maven-plugin/src/main/java/hudson/maven/PomInfo.java

@@ -37,6 +37,7 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 import java.util.ArrayList;
+import javax.annotation.Nonnull;
 
 /**
  * Serializable representation of the key information obtained from Maven POM.
@@ -51,7 +52,7 @@ final class PomInfo implements Serializable {
     
     public static final String PACKAGING_TYPE_PLUGIN = "maven-plugin";
 
-    public final ModuleName name;
+    public final @Nonnull ModuleName name;
 
     /**
      * This is a human readable name of the POM. Not necessarily unique