gradle - how do I build a jar with a lib dir with other jars in it?

In gradle - how can I embed jars inside my build output jar in the lib directory (specifially the lib/enttoolkit.jar and lib/mail.jar)?

If you have all the jars inside a directory (lets call it libs) in your project, you only need this:

jar {
    into('lib') {
        from 'libs'
    }
}

I guess it is more likely that these jars are dependencies of some sort. Then you could do it like this:

configurations {
    // configuration that holds jars to copy into lib
    extraLibs
}
dependencies {
    extraLibs 'org.something:something-dep1:version'
    extraLibs 'org.something:something-dep2:version'
}

jar {
    into('lib') {
        from configurations.extraLibs
    }
}

Lifted verbatim from: http://docs.codehaus.org/display/GRADLE/Cookbook#Cookbook-Creatingafatjar

Gradle 0.9:

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

Gradle 0.8:

jar.doFirst {
    for(file in configurations.compile) {
        jar.merge(file)
    }
}

The above snippets will only include the compile dependencies for that project, not any transitive runtime dependencies. If you also want to merge those, replace configurations.compile with configurations.runtime.

EDIT: only choosing jars you need

Make a new configuration, releaseJars maybe

configurations {
    releaseJars
}

Add the jars you want to that configuration

dependencies {
    releaseJars group: 'javax.mail', name: 'mail', version: '1.4'
    //etc
}

then use that configuration in the jar task outlined above.

simple:

task copyToLib( type: Copy ) {
    into "$buildDir/libs/lib"
    from configurations.runtime
}

jar { dependsOn copyToLib }

run it:

$ gradle jar
...
$ tree build/libs

build/libs
├── your-project-0.0.1.BUILD-SNAPSHOT.jar
└── lib
    ├── akka-actor-2.0.jar
    ├── akka-camel-2.0.jar
    ├── ... ... ...
    ├── spring-expression-3.1.0.RELEASE.jar
    └── zmq-2.1.9.jar

1 directory, 46 files

I also needed to do something similar and wasn't quite able to get what Guus and stigkj suggested working, but got close enough with their help to get this working (Guus' example blew up on the dependencies { compile { extendsFrom myLibs }} closure for me.

apply plugin: 'groovy'

repositories {
    mavenCentral()
}

configurations {
    // custom config of files we want to include in our fat jar that we send to hadoop
    includeInJar
}

dependencies {
    includeInJar 'org.codehaus.groovy:groovy:1.8.6'

    configurations.compile.extendsFrom(configurations.includeInJar)
}

jar {
    into('lib') {
        println "includeInJar: " + configurations.includeInJar.collect { File file -> file }
        from configurations.includeInJar
    }

}

Then running gradle jar and examining the created jar gives me this output, showing that I get the jar file to have groovy as well as all jars that it's dependent on inside the "fat jar":

%  gradle jar                                                                                                                         
includeInJar: [/Users/tnaleid/.gradle/caches/artifacts-8/filestore/org.codehaus.groovy/groovy/1.8.6/jar/553ca93e0407c94c89b058c482a404427ac7fc72/groovy-1.8.6.jar, /Users/tnaleid/.gradle/caches/artifacts-8/filestore/antlr/antlr/2.7.7/jar/83cd2cd674a217ade95a4bb83a8a14f351f48bd0/antlr-2.7.7.jar, /Users/tnaleid/.gradle/caches/artifacts-8/filestore/asm/asm/3.2/jar/9bc1511dec6adf302991ced13303e4140fdf9ab7/asm-3.2.jar, /Users/tnaleid/.gradle/caches/artifacts-8/filestore/asm/asm-tree/3.2/jar/cd792e29c79d170c5d0bdd05adf5807cf6875c90/asm-tree-3.2.jar, /Users/tnaleid/.gradle/caches/artifacts-8/filestore/asm/asm-commons/3.2/jar/e7a19b8c60589499e35f5d2068d09013030b8891/asm-commons-3.2.jar, /Users/tnaleid/.gradle/caches/artifacts-8/filestore/asm/asm-util/3.2/jar/37ebfdad34d5f1f45109981465f311bbfbe82dcf/asm-util-3.2.jar, /Users/tnaleid/.gradle/caches/artifacts-8/filestore/asm/asm-analysis/3.2/jar/c624956db93975b7197699dcd7de6145ca7cf2c8/asm-analysis-3.2.jar]
:compileJava UP-TO-DATE
:compileGroovy UP-TO-DATE
:processResources UP-TO-DATE
:classes UP-TO-DATE
:jar

BUILD SUCCESSFUL

Total time: 3.387 secs

%  jar tvf build/libs/gradletest.jar                                                                                                  
     0 Mon Mar 12 11:40:00 CDT 2012 META-INF/
    25 Mon Mar 12 11:40:00 CDT 2012 META-INF/MANIFEST.MF
     0 Mon Mar 12 11:40:00 CDT 2012 lib/
5546084 Mon Mar 05 13:13:32 CST 2012 lib/groovy-1.8.6.jar
445288 Mon Mar 05 13:13:38 CST 2012 lib/antlr-2.7.7.jar
 43398 Mon Mar 05 13:13:40 CST 2012 lib/asm-3.2.jar
 21878 Mon Mar 05 13:13:40 CST 2012 lib/asm-tree-3.2.jar
 33094 Mon Mar 05 13:13:40 CST 2012 lib/asm-commons-3.2.jar
 36551 Mon Mar 05 13:13:40 CST 2012 lib/asm-util-3.2.jar
 17985 Mon Mar 05 13:13:40 CST 2012 lib/asm-analysis-3.2.jar

Below code could be tried. It depends on the jar task and is of Type Jar

task createJobJar(dependsOn:jar,type:Jar) {
    manifest {
        attributes(
                "Implementation-Title": 'Job '
                ,"Implementation-Version": version
        )
    }
    classifier 'job'
    destinationDir new File("$buildDir")
    into('libs'){
         from configurations.compile
    }
    into('classes'){
        from "$buildDir/classes"
    }
    into('resources'){
        from "$projectDir/src/main/resources"
    }
    into('scripts'){
        from "$projectDir/src/main/scripts"
    }
}

The above code would pack different content inside different directories. Tested on gradle 2.2