QuickTip : Generating project structure using Maven

When you are starting a new project it is very easy to get started if the project structure can be built for you. Maven provides a plugin called maven-archetype-plugin which can help you generate the desired project structure depending on the application that you are trying to build.

The Archetype Plugin allows the user to build archetype containers. These archetype containers contains the pom, default source, test, resources, test-resources, and site-resources files in a specific directory structure. The content of the pom, the default files, and the directory structure depends on the what archetype container was built.

To create a simple java application you can use

mvn archetype:create -DgroupId=[your project's group id] -DartifactId=[your project's artifact id] -DarchetypeArtifactId=maven-archetype-quickstart

Likewise to create a webapp use something like this

Adding project nature to your Maven pom.xml

Let us assume that you have a maven based project. This would mean you have a pom.xml if you are using maven 2.

Now if you execute mvn eclipse:eclipse the maven eclipse plugin generated the required .classpath and .project files so that your project can become a first class eclipse project.

However, by default the project nature added is that for a java project and hence the .project file is generated like this, with the java builder and the java nature.

 

<projectDescription>

<name>my-project</name>

<buildSpec>

<buildCommand>

<name>org.eclipse.jdt.core.javabuilder</name>

</buildCommand>

</buildSpec>

<natures>

<nature>org.eclipse.jdt.core.javanature</nature>

</natures>

</projectDescription>

 

 

QuickTip : How to increase the Java heap memory for Maven 2 on linux

If you get an error OutOfMemory error while doing mvn site, because of all the reports that you are generating, just increase the heap size for maven2. The way to do that on linux.

In your mvn.sh add this as the first line after the copyright and other comments.

export MAVEN_OPTS=”-Xmx512m”

note than Maven 2.0.6 onwards some users have reported that the double quotes give problems, hence you might want to use

export MAVEN_OPTS=-Xmx512m