Maven – How to Build Jar Files and Obtain Dependencies

This article represents facts on what would it take to build one or more jar files for a given framework/library using Maven, provided the framework’s downloadable files consisted of pom.xml. Please feel free to comment/suggest if I missed to mention one or more important points. Also, sorry for the typos.

So far, whenever I came across pom.xml file in the framework that I downloaded in order to get the jar file, I hated it. I used to, then, go to internet and get the compiled jar file(s) for the framework/library. And, good thing is that I have been able to get my work done. This was purely out of my laziness that I did not use to build using maven.Then, I got a chance to work with Twitter HBC library (Java) for integrating with Twitter. And, I downloaded it and wanted to get one or more jar files. And, once again, I came across a pom.xml in root folder and unique pom.xml files in hbc-core, hbc-twitter4j and hbc-examples folder. This time, I decided to build the hbc jar files on my system.Following are some of the steps I took to build hbc jar files and get dependencies to run the program using hbc jar files.

• Download and install Maven. Anyone wanting to install/configure Maven, go to this Maven in 5 Minutes page. It clearly states what needs to be done to install/configure Maven. Once configured, open a command prompt and execute command “mvn -version”. If the version information of Maven is displayed, you are all set. Once determined, go to the folder which consists of pom.xml file. In present case, go to hbc root folder.
• Go to hbc root folder, hbc-master.
• Execute following command to build the hbc jar files and also obtain the dependencies (jar files) required to run the library. Command is “mvn clean install -U dependency:copy-dependencies“. This command built the source file and created two different jar files in hbc-twitter4j/target (hbc-twitter4j-2.2.1-SNAPSHOT.jar) and hbc-core/target (hbc-core-2.2.1-SNAPSHOT.jar). Further to that, it downloaded all the dependent jar files in repective target/dependency folder.