Maven: Creating deployable distribution: Part 2: creating fat jar

In the Part 1 of this, we had seen how to use the appassembler plugin to create a distribution tar. In this increment, we will see how to use the Maven assembly plugin to create a uber jar or fat jar. A uber jar or fat jar is a single jar having the contents of all the dependencies needed for the project. Again, we will be using the maven-distribution-example as reference. This project would need the project rmi-service-api to compile. We have created a profile called uber-jar:

		
			uber-jar
			
				
					
						org.apache.maven.plugins
						maven-assembly-plugin
						2.6
						
							
								create-uber-jar
								package
								
									single
								
								
									
										jar-with-dependencies
									
								
							
							
								assemble-all
								package
								
									single
								
								
									src/assembly/uber-jar-assembly-descriptor.xml
								
							
						
					
				
			
		

The assembly plugin uses a pre-fabricated descriptor called jar-with-dependencies. This would condense all dependencies into the single fat jar.
Note there are 2 executions. The first one creates the uber jar and the second one takes that uber jar and the readme.txt and creates a zip file. It does this by using the below assembly descriptor (uber-jar-assembly-descriptor.xml):

	uber-jar
	
		zip
	
	false
	
		
			${project.basedir}/src/static
			/
			
				readme.txt
			
		
		
			${project.build.directory}
			/
			
				${project.name}-${project.version}-jar-with-dependencies.jar
			
		
	

The uber jar can be generated by:

mvn clean package -P uber-jar

The sources can be found here: https://github.com/paawak/blog/tree/master/code/maven-ant-assembly-example