Building a fat jar using maven

Question

I have a code base which I want to distribute as jar  It also have dependency on external jars  which I want to bundle in the final jar    I heard that this can be done using maven-assembly-plug-in  but I don t understand how  Could someone point me to some examples    Right now  I m using fat jar to bundle the final jar  I want to achieve the same thing using maven

User · Answer

You can use the onejar-maven-plugin for packaging. Basically, it assembles your project and its dependencies in as one jar, including not just your project jar file, but also all external dependencies as a "jar of jars", e.g.

<build>
    <plugins>
        <plugin>
            <groupId>com.jolira</groupId>
            <artifactId>onejar-maven-plugin</artifactId>
                <version>1.4.4</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>one-jar</goal>
                        </goals>
                    </execution>
                </executions>
        </plugin>
    </plugins>
</build>

Note 1: Configuration options is available at the project home page.

Note 2: For one reason or the other, the onejar-maven-plugin project is not published at Maven Central. However jolira.com tracks the original project and publishes it to with the groupId com.jolira.

User · Answer

Maybe you want maven-shade-plugin  bundle dependencies  minimize unused code and hide external dependencies to avoid conflicts    lt build gt       lt plugins gt           lt plugin gt               lt groupId gt org apache maven plugins lt  groupId gt               lt artifactId gt maven-shade-plugin lt  artifactId gt               lt version gt 3 1 1 lt  version gt               lt executions gt                   lt execution gt                       lt phase gt package lt  phase gt                       lt goals gt                           lt goal gt shade lt  goal gt                       lt  goals gt                       lt configuration gt                           lt minimizeJar gt true lt  minimizeJar gt                           lt createDependencyReducedPom gt true lt  createDependencyReducedPom gt                           lt dependencyReducedPomLocation gt                                java io tmpdir  dependency-reduced-pom xml                          lt  dependencyReducedPomLocation gt                           lt relocations gt                               lt relocation gt                                   lt pattern gt com acme coyote lt  pattern gt                                   lt shadedPattern gt hidden coyote lt  shadedPattern gt                               lt  relocation gt                           lt  relocations gt                       lt  configuration gt                   lt  execution gt               lt  executions gt           lt  plugin gt       lt  plugins gt   lt  build gt    References    http   maven apache org plugins maven-shade-plugin plugin-info html http   maven apache org plugins maven-shade-plugin shade-mojo html

User · Answer

An alternative is to use the maven shade plugin to build an uber-jar    lt plugin gt       lt groupId gt org apache maven plugins lt  groupId gt       lt artifactId gt maven-shade-plugin lt  artifactId gt       lt version gt  Your Version Here  lt  version gt       lt configuration gt               lt  -- put your configurations here -- gt       lt  configuration gt       lt executions gt               lt execution gt                       lt phase gt package lt  phase gt                       lt goals gt                               lt goal gt shade lt  goal gt                       lt  goals gt               lt  execution gt       lt  executions gt   lt  plugin gt

User · Answer

Note  If you are a spring-boot application  read the end of answer  Add following plugin to your pom xml The latest version can be found at        lt build gt       lt plugins gt           lt plugin gt               lt groupId gt org apache maven plugins lt  groupId gt               lt artifactId gt maven-assembly-plugin lt  artifactId gt               lt version gt CHOOSE LATEST VERSION HERE lt  version gt               lt configuration gt                   lt descriptorRefs gt                       lt descriptorRef gt jar-with-dependencies lt  descriptorRef gt                   lt  descriptorRefs gt               lt  configuration gt               lt executions gt                   lt execution gt                       lt id gt assemble-all lt  id gt                       lt phase gt package lt  phase gt                       lt goals gt                           lt goal gt single lt  goal gt                       lt  goals gt                   lt  execution gt               lt  executions gt           lt  plugin gt       lt  plugins gt   lt  build gt        After configuring this plug-in  running mvn package will produce two jars  one containing just the project classes  and a second fat jar with all dependencies with the suffix  -jar-with-dependencies    if you want correct classpath setup at runtime then also add following plugin   lt plugin gt       lt groupId gt org apache maven plugins lt  groupId gt       lt artifactId gt maven-jar-plugin lt  artifactId gt       lt configuration gt           lt archive gt               lt manifest gt                   lt addClasspath gt true lt  addClasspath gt                   lt mainClass gt fully qualified MainClass lt  mainClass gt               lt  manifest gt           lt  archive gt       lt  configuration gt   lt  plugin gt      For spring boot application use just following plugin  choose appropriate version of it    lt plugin gt       lt groupId gt org springframework boot lt  groupId gt       lt artifactId gt spring-boot-maven-plugin lt  artifactId gt       lt configuration gt           lt fork gt true lt  fork gt           lt mainClass gt   start-class  lt  mainClass gt       lt  configuration gt       lt executions gt           lt execution gt               lt goals gt                   lt goal gt repackage lt  goal gt               lt  goals gt           lt  execution gt       lt  executions gt   lt  plugin gt

User · Answer

actually  adding the    lt archive gt      lt manifest gt       lt addClasspath gt true lt  addClasspath gt       lt packageName gt com some pkg lt  packageName gt                            lt mainClass gt com MainClass lt  mainClass gt     lt  manifest gt   lt  archive gt    declaration to maven-jar-plugin does not add the main class entry to the manifest file for me  I had to add it to the maven-assembly-plugin in order to get that in the manifest

User · Answer

You can use the maven-shade-plugin   After configuring the shade plugin in your build the command mvn package will create one single jar with all dependencies merged into it

[maven] Building a fat jar using maven

Examples related to maven

Examples related to jar

Examples related to maven-assembly-plugin