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Maven package with dependencies

Problem:

How to use Maven to package a project with dependencies? The solution is to use maven-assembly-plugin as in the following example.

Solution:

Here we’ll use very simple Maven project with compile dependency on Apache Commons Lang3 library. Packaging of the bundle is done by maven-assembly-plugin according to a configuration. Fortunately, the plugin comes with a couple of ready to use configurations, one of which is jar-with-dependencies:

<?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.farenda.java</groupId>
    <artifactId>solved</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.4</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <version>2.5.5</version>
                <configuration>
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

Sample Java code using our dependency (Apache Commons Lang3):

package com.farenda.java;

import org.apache.commons.lang3.LocaleUtils;

import java.util.Locale;

public class JavaSolved {

    public static void main(String[] args) {
        for (Locale locale : LocaleUtils.availableLocaleSet()) {
            System.out.printf("Country: %s, language: %s%n",
                    locale.getCountry(), locale.getLanguage());
        }
    }
}

Now, running mvn assembly:assembly command will tell Maven to run the assembly plugin with configuration from the pom.xml.

All project classes with dependencies have been packed into target/solved-0.0.1-SNAPSHOT-jar-with-dependencies.jar. Here are sample entries that confirm correct packaging:

-rw-r--r--      1067  21-Aug-2015  18:16:20  com/farenda/java/JavaSolved.class
-rw-r--r--      7004   3-Apr-2015  14:30:26  org/apache/commons/lang3/AnnotationUtils.class
-rw-r--r--       246   3-Apr-2015  14:30:26  org/apache/commons/lang3/builder/Builder.class

As you can see dependent JAR has been unpacked and repackaged with project code. Such single JAR is easier to distribute than whole bunch.

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