build.gradle

apply plugin: 'android-library'

android {
    compileSdkVersion 19
    buildToolsVersion "19.1"

    defaultConfig {
        minSdkVersion 7
        targetSdkVersion 16
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            runProguard false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
        }
    }
}

dependencies {
    compile 'com.android.support:appcompat-v7:+'
}

// This is the actual solution, as in http://stackoverflow.com/a/19037807/1002054
task clearJar(type: Delete) {
    delete 'build/libs/myCompiledLibrary.jar'
}

task makeJar(type: Copy) {
    from('build/bundles/release/')
    into('build/libs/')
    include('classes.jar')
    rename ('classes.jar', 'myCompiledLibrary.jar')
}

makeJar.dependsOn(clearJar, build)