Building an uberjar with Gradle

Question

I want to build an uberjar (AKA fatjar) that includes all the transitive dependencies of the project. What lines do I need to add to build.gradle?

This is what I currently have:

task uberjar(type: Jar) {
    from files(sourceSets.main.output.classesDir)

    manifest {
        attributes 'Implementation-Title': 'Foobar',
                'Implementation-Version': version,
                'Built-By': System.getProperty('user.name'),
                'Built-Date': new Date(),
                'Built-JDK': System.getProperty('java.version'),
                'Main-Class': mainClassName
    }
}

Cocainism

You may want to try using the application plug-in instead. – Hardden

This will work as long as you do not have any dependencies. But once your project has dependencies those won't get bundled into the uberjar. – Raynata

Answer 1

Have you tried the fatjar example in the gradle cookbook?

What you're looking for is the shadow plugin for gradle

Beg

Thank you for the pointer. It helped. Though I hit another issue which was solved by a bit of googling. I'll add another answer expanding on that. – Cocainism

It looks like the cookbook now requires a login. As this is exactly what I am looking for, could you paste the recipe in here please? – Thematic

@tarzan three years later, and I'd now use the shadow plugin github.com/johnrengelman/shadow – Beg

this is very simple and worked the first time (after trying many other "answers": #23739176 – Sylvie

Things change in 3 years. And I'd still use the shadow plugin ;-) – Beg

shadowjar isn't very well-maintained. See github.com/johnrengelman/shadow/issues/476 and other critical issues that have gone unfixed for months. – Equalizer

Answer 2

I replaced the task uberjar(.. with the following:

jar {
    from(configurations.compile.collect { it.isDirectory() ? it : zipTree(it) }) {
        exclude "META-INF/*.SF"
        exclude "META-INF/*.DSA"
        exclude "META-INF/*.RSA"
    }

    manifest {
        attributes 'Implementation-Title': 'Foobar',
                'Implementation-Version': version,
                'Built-By': System.getProperty('user.name'),
                'Built-Date': new Date(),
                'Built-JDK': System.getProperty('java.version'),
                'Main-Class': mainClassName
    }
}

The exclusions are needed because in their absence you will hit this issue.

Cocainism

I think it should use configurations.runtime to include all runtime dependencies – Jaala

i needed to add with jar below manifest to get the files in java/main/resources in the uberjar – Stroud

That worked for me! Without the exclude part it was killing me with SecurityException and with this fix it works! – Discrepancy

Best to even use the sourceSets.getByName('main').runtimeClasspath – Kentledge

anybody know what this would look like in kotlin (for the build.gradle,kts file) ? – Aftershaft

Answer 3

Simply add this to your java module's build.gradle.

mainClassName = "my.main.Class"

jar {
  manifest { 
    attributes "Main-Class": "$mainClassName"
  }  

  from {
    configurations.compile.collect { it.isDirectory() ? it : zipTree(it) }
  }
}

This will result in [module_name]/build/libs/[module_name].jar file.

Incompliant

but what is that code? What does configurations.compile.collect { it.isDirectory() ? it : zipTree(it) } do? – Nievelt

@SamRedway configurations.compile.collect collects stuff from compile The ternary lets it pull in both folders and zip-files (like jars) as if they were also folders – Yanirayank

I haven't tried the other versions posted here, but this one works nicely and is nice and simple. – Pattani

This answer excludes any runtime or runtimeOnly declared dependencies, which will cause the application to break at runtime. – Kentledge

@Kentledge You can replace compile with runtimeClasspath as specified in this answer. – Permanent

Answer 4

I found this project very useful. Using it as a reference, my Gradle uberjar task would be

task uberjar(type: Jar, dependsOn: [':compileJava', ':processResources']) {
    from files(sourceSets.main.output.classesDir)
    from configurations.runtime.asFileTree.files.collect { zipTree(it) }

    manifest {
        attributes 'Main-Class': 'SomeClass'
    }
}

Ventilate

i get Invalid signature file digest for Manifest main attributes when i try this – Abm

you need exclude "META-INF/*.SF" exclude "META-INF/*.DSA" exclude "META-INF/*.RSA" like missingfaktor's answer – Abm

Does not seem to work with Gradle 5.3.1: "Could not get unknown property 'classesDir' for main classes of type org.gradle.api.internal.tasks.DefaultSourceSetOutput." – Molal

it gives me java.lang.UnsupportedOperationException – Catacaustic