java - How To: Eclipse Maven install build jar with dependencies

Question

I am using Eclipse Maven (m2e) inside Eclipse and I am running my project like this:

My pom.xml looks like this:

<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/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>ro.project</groupId>
    <packaging>jar</packaging>
    <version>1.0-SNAPSHOT</version>
    <name>ro.project</name>

    <properties>
        <org.springframework.version>3.1.1.RELEASE</org.springframework.version>
        <org.hibernate.version>4.1.0.Final</org.hibernate.version>
    </properties>
    <dependencies>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${org.springframework.version}</version>
        </dependency>
    <build>
        <plugins>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>
                    <archive>
                        <manifest>
                            <addClasspath>true</addClasspath>
                            <classpathPrefix>lib/</classpathPrefix>
                            <mainClass>ro.project.ProjectServer</mainClass>
                        </manifest>
                    </archive>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-antrun-plugin</artifactId>
                <dependencies>
                    <dependency>
                        <groupId>com.sun</groupId>
                        <artifactId>tools</artifactId>
                        <version>1.7.0_02</version>
                        <scope>system</scope>
                        <systemPath>${java.home}/../lib/tools.jar</systemPath>
                    </dependency>
                </dependencies>
                <executions>
                    <execution>
                        <id>ant-magic</id>
                        <phase>prepare-package</phase>
                        <goals>
                            <goal>run</goal>
                        </goals>
                        <configuration>
                            <tasks>
                                <property name="compile_classpath" refid="maven.compile.classpath" />
                                <property name="runtime_classpath" refid="maven.runtime.classpath" />
                                <property name="test_classpath" refid="maven.test.classpath" />
                                <property name="plugin_classpath" refid="maven.plugin.classpath" />

                                <ant antfile="${basedir}/clientExport.xml" target="export-all" />
                            </tasks>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

    <artifactId>project-core</artifactId>
    <url>http://www.project.ro</url>
</project>

After I run the maven install it is working...

Maven run configurations:

The problem is that my generated .jar it doesn't have the dependencies included.... How can I configure pom.xml to include all my dependencies in .jar format and not unpacked.. because it seems that unpacked are not working correct...

To be sure that including all jars is ok.. I downloaded and added each library into jar's /lib folder and the jar is running... so.. my only question is: How can I configure pom.xml in order to add all my dependencies in jar format?

I tried all methods:

1. assembly:assembly
2. assembly:single
3. assembly:single with my descriptor (an assemble.xml file) but it wasn't working
4. maven copy dependencies plugin but still not working with Eclipse Maven - m2e

I am out of solutions... can anyone tell me a proper way to add my dependencies in jar? I can't believe that maven is so complex and I can't find an answer to my question everywhere..

Thank you in advance

Answer 1

There are a couple of ways of doing this.

1) If you want an uber-jar (repacked with all dependencies), look into using and configuring the maven-shade-plugin:

  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-shade-plugin</artifactId>
        <version>1.6</version>
        <executions>
          <execution>
            <phase>package</phase>
            <goals>
              <goal>shade</goal>
            </goals>
            <configuration>
              <transformers>
                <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                  <mainClass>com.group.id.Launcher1</mainClass>
                </transformer>
              </transformers>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>

This will unpack all dependencies and merge them into one JAR file.

2) If you want to deliver a bundle (zip, tar.gz, etc) with the unpacked JAR files in the bundle (perhaps under lib/) then you need to look into the maven-assembly-plugin:

  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-assembly-plugin</artifactId>
        <version>2.3</version>
        <executions>
          <execution>
            <id>create-distro</id>
            <phase>package</phase>
            <goals>
              <goal>single</goal>
            </goals>
            <configuration>
              <descriptors>
                <descriptor>src/main/assembly/dist.xml</descriptor>
              </descriptors>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>

Note that this requires an assembly descriptor src/main/assembly/dist.xml and example looks like this:

<assembly xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.0">
  <id>distribution</id>
  <formats>
    <format>zip</format>
  </formats>

  <dependencySets>
    <dependencySet>
      <useProjectArtifact>false</useProjectArtifact>
      <useTransitiveDependencies>false</useTransitiveDependencies>
      <unpack>false</unpack>
      <scope>runtime</scope>
      <fileMode>0755</fileMode>
      <directoryMode>0755</directoryMode>
      <outputDirectory>bin</outputDirectory>

      <includes>
        <include>com.group.id:project-launch1</include>
        <include>com.group.id:project-launch2</include>
      </includes>

    </dependencySet>
    <dependencySet>
      <useProjectArtifact>false</useProjectArtifact>
      <useTransitiveDependencies>true</useTransitiveDependencies>
      <unpack>false</unpack>
      <scope>runtime</scope>
      <fileMode>0644</fileMode>
      <directoryMode>0755</directoryMode>
      <outputDirectory>lib</outputDirectory>

      <includes>
        <include>com.group.id:project-lib1</include>
        <include>com.group.id:project-lib2</include>
        <include>com.group.id:project-lib3</include>
        <include>com.group.id:project-lib4</include>
      </includes>

    </dependencySet>
  </dependencySets>
</assembly>

And since you are now assembling dependencies, you have better define the dependency in the pom.xml, like so:

  <dependencies>
    <dependency>
      <groupId>com.group.id</groupId>
      <artifactId>project-launch1</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <type>jar</type>
    </dependency>
    <dependency>
      <groupId>com.group.id</groupId>
      <artifactId>project-launch2</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <type>jar</type>
    </dependency>
    <dependency>
      <groupId>com.group.id</groupId>
      <artifactId>project-lib1</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <type>jar</type>
    </dependency>
    ... and so on ...
  </dependencies>

3) If you are delivering a bundle with an executable JAR file launcher, you will likely need to add a maven-jar-plugin configuration in addition to the maven-assembly-plugin:

  <dependencies>
    <dependency>
      <groupId>com.group.id</groupId>
      <artifactId>project-lib1</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <type>jar</type>
    </dependency>
    <dependency>
      <groupId>com.group.id</groupId>
      <artifactId>project-lib2</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <type>jar</type>
    </dependency>
    <dependency>
      <groupId>com.group.id</groupId>
      <artifactId>project-lib3</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <type>jar</type>
    </dependency>
    ... and so on ...
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <artifactId>maven-jar-plugin</artifactId>
        <configuration>
          <archive>
            <addMavenDescriptor>false</addMavenDescriptor>
            <compress>true</compress>
            <manifest>
              <mainClass>com.group.id.Launcher1</mainClass>
              <addClasspath>true</addClasspath>
              <classpathPrefix>../lib/</classpathPrefix>
            </manifest>
          </archive>
        </configuration>
      </plugin>
    </plugins>
  </build>

Note that the "addClasspath" directive adds the project dependencies to the class path. This is needed for JAR launchers, as they explicitly ignore all CLASSPATH environmental variables.