Packing your own maven dependencies

Lately, I’ve found myself repeating always the same dependencies for my pet projects and katas. Usually, I prefer maven to hold my java dependencies, organized in a java project.

This is how most of them look like:

<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.gmaur.legacycode</groupId>
  <artifactId>legacyutils</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  
  <dependencies>
  
  	<dependency>
  		<groupId>org.hamcrest</groupId>
  		<artifactId>hamcrest-all</artifactId>
  		<version>1.3</version>
  		<scope>test</scope>
  	</dependency>
  
  	<dependency>
  		<groupId>junit</groupId>
  		<artifactId>junit</artifactId>
  		<version>4.11</version>
  		<scope>test</scope>
  	</dependency>

  	<dependency>
  		<groupId>org.mockito</groupId>
  		<artifactId>mockito-all</artifactId>
  		<scope>test</scope>
  		<version>2.0.2-beta</version>
	</dependency>
  </dependencies>

  <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <version>2.18.1</version>
                <configuration>
                    <includes>
                        <include>**/**Test.java</include>
                        <include>**/**Should.java</include>
                    </includes>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

Note: the org.apache.maven.plugins:maven-surefire-plugin is to make maven execute the tests that end in *Should.

Now, the dependency versions and plugin configuration is repeated in all the projects, which is plenty of repetition.

Enter JitPack.io

With the tool JitPack.io, you can generate your own dependencies. A guide on how to use it can be found here

I’ve published my own java dependency (originally a github release)

A pom.xml in the new style is here:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example.spike</groupId>
    <artifactId>lambdatesting</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <parent>
        <groupId>com.github.alvarogarcia7</groupId>
        <artifactId>java-parent</artifactId>
        <version>v0.0.1</version>
    </parent>

    <repositories>
        <repository>
            <id>jitpack.io</id>
            <url>https://jitpack.io</url>
        </repository>
    </repositories>

    <dependencies>
        <dependency>
            <groupId>com.github.alvarogarcia7</groupId>
            <artifactId>java-parent</artifactId>
            <version>v0.0.1</version>
            <type>pom</type>
        </dependency>

        <dependency>
            <groupId>org.hamcrest</groupId>
            <artifactId>hamcrest-all</artifactId>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
        </dependency>

        <dependency>
            <groupId>org.mockito</groupId>
            <artifactId>mockito-all</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

It does not need the plugin configuration nor the dependency versions. The downside is that it needs to be as the parent pom.

Acknowledgments

Thanks to Manuel for encouraging me to write this article