[MNG-8121] NullPointerException at org.apache.maven.artifact.repository.metadata.Metadata.merge (Metadata.java:293)

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.9.6
• Fix Version/s: 3.9.7, 4.0.0, 4.0.0-beta-3
• Component/s: Artifacts and Repositories
• Environment: Maven 3.9.6 ; maven-plugin-plugin 3.13.0 ; org.sonatype.plugins:nexus-staging-maven-plugin:1.6.13
• Assignee: Tamas Cservenak
• Reporter: Gili
• Created: 15/May/24 01:40
• Updated: 16/May/24 17:03
• Resolved: 15/May/24 17:33

Description

TL;DR org.apache.maven.artifact.repository.metadata.Metadata.merge (Metadata.java:293) throws NullPointerException if previous releases of a plugin did not have a goalPrefix set.
 
At least, this is my interpretation of what is going on.
 
Background
-------------
 
I have an open-source project at https://github.com/cmake-maven-project/cmake-maven-project/tree/v3.27.1-b1 with the following coordinates:
 
<groupId>com.googlecode.cmake-maven-project</groupId>
<artifactId>cmake</artifactId>
 

If I upgrade "maven-plugin-plugin" from version 3.10.1 to 3.13.0 I am forced to set "<goalPrefix>" because of https://issues.apache.org/jira/browse/MPLUGIN-450 and https://github.com/apache/maven-plugin-tools/commit/ed4774bcd8b8d2d1f7ff1196cf7644054cb3ae14#diff-624cbd32cd7fc0f3f9154fbec92b8a1aebb04614360b4a0b5fc28a407e99d743L96

 

In my particular case, I set "<goalPrefix>cmake-binaries</goalPrefix>" inside cmake-binaries-plugin/pom.xml.

Now, when I try deploying a release to Maven Central I get the following exception stack trace:

 
 

java.lang.NullPointerException
    at org.apache.maven.artifact.repository.metadata.Metadata.merge (Metadata.java:293)
    at org.apache.maven.artifact.repository.metadata.AbstractRepositoryMetadata.updateRepositoryMetadata (AbstractRepositoryMetadata.java:99)
    at org.apache.maven.artifact.repository.metadata.AbstractRepositoryMetadata.storeInLocalRepository (AbstractRepositoryMetadata.java:59)
    at org.apache.maven.artifact.repository.metadata.MetadataBridge.merge (MetadataBridge.java:56)
    at org.eclipse.aether.internal.impl.DefaultDeployer.upload (DefaultDeployer.java:399)
    at org.eclipse.aether.internal.impl.DefaultDeployer.deploy (DefaultDeployer.java:294)
    at org.eclipse.aether.internal.impl.DefaultDeployer.deploy (DefaultDeployer.java:202)
    at org.eclipse.aether.internal.impl.DefaultRepositorySystem.deploy (DefaultRepositorySystem.java:393)
    at org.apache.maven.artifact.deployer.DefaultArtifactDeployer.deploy (DefaultArtifactDeployer.java:131)
    at org.sonatype.nexus.maven.staging.deploy.strategy.AbstractDeployStrategy.deployUp (AbstractDeployStrategy.java:213)
    at org.sonatype.nexus.maven.staging.deploy.strategy.StagingDeployStrategy.finalizeDeploy (StagingDeployStrategy.java:125)
    at org.sonatype.nexus.maven.staging.deploy.DeployMojo.execute (DeployMojo.java:213)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo (DefaultBuildPluginManager.java:126)

 
I assume that this is caused by preExisting.getPrefix() returning null, but I have no idea why this is happening. Perhaps this is caused by previous versions not have a goalPrefix set? Shouldn't the implementation handle this possibility?

Issue Links

• relates to: MBUILDCACHE-6 Rename schemas to be inlined with other schemas
• relates to: MNG-7375 Potential NPE in o.a.m.artifact.repository.metadata.Metadata.merge(...) with invalid/incomplete plugin metadata
• links to: GitHub Pull Request #1508
• links to: GitHub Pull Request #1509