Maven archetypes are the project templates which can help us quickly create a maven starter project based on its type. It’s a great tool to bootstrap a maven project with least effort.
There are wide options of archetypes available to us. Some of the popular archetypes include – maven-archetype-quickstart, maven-archetype-webapp, maven-archetype-archetype. To create a maven project with a specific archetype, we can use:
This command will ask us to choose an archetype and will then create our maven project from it.
We can also define our custom archetype. It is specifically helpful when we have many modular apps in our project which share the same structure. We can simply standardize a template to use for creating our project modules.
In this tutorial, we’ll learn to create and use our own Maven Archetype.
It is pretty easy to create a Maven Archetype from one of our existing projects. All we need to do is to execute:
from the root directory of our project.
Optionally, we can directly generate an archetype project using archetype-maven-plugin:
mvn archetype:generate -B -DarchetypeArtifactId=maven-archetype-archetype
Either way, after successful archetype creation, we would see archetype files generated at target/generated-sources/archetype.
Now that we have generated the archetype structure, we can choose to:
Let’s quickly look at what does the archetype-metadata.xml contains.
The archetype-metadata.xml stores the metadata of our archetype. It is present at the location – /META-INF/maven folder within the jar.
The metadata file structure looks similar to:
<archetype-descriptor ... name="my-custom-archetype"> <requiredProperties> <requiredProperty key="name"> <defaultValue>ProgrammerGirl</defaultValue> </requiredProperty> </requiredProperties> <fileSets> <fileSet filtered="true" packaged="true"> <directory>src/main/java</directory> <includes> <include>**/*.java</include> </includes> </fileSet> </fileSets> <modules> <module name="sub-module-1"></module> <module name="sub-module-2"></module> </modules> </archetype-descriptor>
Here are a few important tags and their purpose:
Once we are done with modifications in our pom.xml and archetype-metadata.xml files, we can build our archetype project.
Let’s go to the path /generated-sources/archetype and execute:
mvn clean install
It will install the plugin in our local repository. We can cross-check whether our newly created archetype is present in our local repository:
mvn archetype:generate -DarchetypeCalalog=local
By now, we have successfully installed our custom archetype in our local repository. To generate a project from this newly created archetype, we’ll use:
mvn archetype:generate -DarchetypeGroupId=com.programmergirl.archetypes -DarchetypeArtifactId=my-custom-archetype -DarchetypeVersion=1.0-SNAPSHOT -DgroupId=com.programmergirl -DartifactId=sample-project -Dversion=1.0-SNAPSHOT
where com.programmergirl.archetypes & my-custom-archetype are the groupId and artifactId of the main archetype project we created earlier. The parameters -DgroupId and -DartifactId specify the groupId and artifactId of newly generated project.
In this tutorial, we discussed how to create a custom maven archetype and use it to generate multiple projects.