Creating JAR with Dependencies in Maven

Question

Creating JAR with Dependencies in Maven

Navigation

#1 by (5 votes)
#2 by (4 votes)

9

I want to use Maven to generate the JAR with its dependencies in .jar format, the solutions I found are not valid.

Eclipse has three ways to generate an executable JAR.

Extract required libraries into gerenated JAR

Package required libraries into generated JAR < I use this in Eclipse.

Copy required libraries into a subfolder next to the generated JAR

And does Maven have a form equivalent to Eclipse?

Using maven-jar-plugin

   <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-jar-plugin</artifactId>
            <version>2.4</version>
            <configuration>
                <archive>
                    <manifest>
                        <mainClass>qualquer.que.seja.seu.pacote.ClasseMain</mainClass>
                    </manifest>
                </archive>
            </configuration>
        </plugin>

Problem: This mode generates a JAR with no dependencies in .jar format.

Using maven-assemply-plugin

<plugin>
    <artifactId>maven-assembly-plugin</artifactId>
    <configuration>
        <archive>
            <manifest>
                <mainClass>qualquer.que.seja.seu.pacote.ClasseMain</mainClass>
            </manifest>
        </archive>
        <descriptorRefs>
            <descriptorRef>jar-with-dependencies</descriptorRef>
        </descriptorRefs>
    </configuration>
</plugin>

Problem: Generates a JAR with the "extracted" dependencies out of the .jars format.

java eclipse maven jar

asked by anonymous 06.03.2014 / 13:08

2 answers

4

You have not set up how maven-assembly-plugin will run, that is, which goal and which phase of maven as well. To package a jar with dependencies during the package phase, the configuration looks like this:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-assembly-plugin</artifactId>
    <version>2.4</version>
    <configuration>
        <archive>
            <manifest>
                <mainClass>qualquer.que.seja.seu.pacote.ClasseMain</mainClass>
            </manifest>
        </archive>
        <descriptorRefs>
            <descriptorRef>jar-with-dependencies</descriptorRef>
        </descriptorRefs>
    </configuration>
    <executions>
        <execution>
            <phase>package</phase>
            <goals>
                <goal>attached</goal>
            </goals>
        </execution>
    </executions>
</plugin>

06.03.2014 / 13:22

Scrypt, Bcrypt or anything else Entity Framework is saving duplicate values when saving entities with relationship N to N

score 5 · Accepted Answer

There is also Maven Shade Plugin that allows you to package the artifact into a super-jar , including its dependencies, and even rename the packages to some dependencies if you wish.

See an example:

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-shade-plugin</artifactId>
        <version>2.2</version>
        <executions>
          <execution>
            <phase>package</phase>
            <goals>
              <goal>shade</goal>
            </goals>
            <configuration>
              <transformers>
                <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                  <mainClass>org.sonatype.haven.HavenCli</mainClass>
                </transformer>
              </transformers>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  ...
</project>

In addition to putting everything together into a single jar, which makes it very easy to distribute for download, for example, Shade also allows you to rename dependency packages, helping a lot in cases where classpath, for example.

It's important to note that shade and assembly plugins are not direct competitors, although the two allow packaging the dependencies in a jar. In the case of packaging, the assembly is more powerful, flexible and complicated. The shade has fewer features, but to create an uber-jar it is more direct and simple.