maven, execution tag, id tag missing

Question

I\'m looking at the plugin section of a pom I\'m inspecting and found this:

    org.apache.maven.plugins
    

        

Answer 1

For Maven 3.0.x at least, when not specified, the ID for an execution is default-goalName. So for the example you have, the ID would be default-check. The value default-cli may also be used to configure command line executions.

The execution IDs are used when creating the effective POM from the POM itself, any parent POMs (including the Maven super POM), and settings.xml. Maven merges configuration for plugin executions having the same ID across these POMs. Here's an example. Assume this plugin config is in a parent POM (only Maven super POM is higher up in the hierarchy.

  org.apache.maven.plugins
  maven-jar-plugin
  
    
    
      default-jar
      
        firstJar
        true
      
    

    
    
      another-jar
      package
      
        jar
      
      
        duplicateJar
      
    

    
    
      default-cli
      
        cmdLineJar
      
    
  

With the above config:

• mvn clean package - builds firstJar.jar and duplicateJar.jar
• mvn jar:jar - builds cmdLineJar.jar (note, no clean lifecycle!)
• mvn clean jar:jar - removes target dir, builds empty (except for manifest) cmdLineJar.jar; because jar:jar does not run the full lifecycle, just one goal
• mvn clean prepare-package jar:jar - runs lifecycle thru prepare-package, then builds a non-empty cmdLineJar.jar