Create a Groovy executable JAR with Gradle

Question

This is my gradle build script.

apply plugin: \'groovy\'

project.group = \"test.tree\"
archivesBaseName = \"tree\"
project.version = \"1.0\"
manifest.mainAt         


        

Answer 1

I got the same issue, after adding jar block in build.gradle then it works.

jar {
  manifest {
    attributes 'Main-Class': 'demo.Demo'
  }
  from { configurations.compile.collect { it.isDirectory() ? it : zipTree(it) } }
}

Answer 2

What you are looking for is the application plugin which allows you build a standalone JVM application including all dependencies and run scripts.

apply plugin:'application'
mainClassName = 'test.tree.App'

EDIT:

This should create the uberjar you want:

task uberjar(type: Jar) {
    from files(sourceSets.main.output.classesDir)
    from configurations.runtime.asFileTree.files.collect { zipTree(it) }

    manifest {
        attributes 'Main-Class': 'test.tree.App'
    }
}

Answer 3

the following code is also ok,use spring boot plugin

buildscript {
    ext {
        springBootVersion = '1.2.6.RELEASE'
    }
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
    }
}

apply plugin: 'groovy'
apply plugin: 'eclipse'
apply plugin: 'spring-boot'


sourceCompatibility = 1.8
targetCompatibility = 1.8

repositories {
    mavenCentral()
}


sourceSets {
    main {
        groovy {
            srcDirs = ['src']
        }
    }

    /*test {
        groovy {
            srcDirs = ['test/groovy']
        }
    }*/
}

dependencies {
    compile "com.alibaba:fastjson:1.1.34"
    compile 'org.codehaus.groovy:groovy-all:2.4.5'
    //testCompile group: 'junit', name: 'junit', version: '4.8.2'
}
springBoot {
    backupSource = false
    mainClass = "com.zhb.hello.Hello"
}
jar{
    baseName = 'hellogroovy'
    version = '1.1.0'
}

Answer 4

I would throw in a vote for the shadow gradle plugin. It is capable of building uber jars and is quite versatile and capable of things like class relocation to prevent dependency hell.

I will not get into comparing the two plugins, but I will go as far as saying that I have gravitated towards using shadow from having used application in the past because of the added features.

When I get tired of the startup times of @Grab based groovy scripts, I tend to write a gradle build file using the shadow plugin even for single file groovy scripts. An example gradle build file capable of building an uber jar of a groovy script file in the current directory. The main class name needs to correspond to the script file name:

repositories { 
  jcenter()
  mavenCentral()
}

defaultTasks = ['shadowJar']
version      = "1.0"

dependencies {
  compile "org.codehaus.groovy:groovy:2.4.7", 
          "commons-cli:commons-cli:1.2"
}

sourceSets {
  main {
    groovy {
        srcDirs = [rootDir]
    }
  }
}

project.tasks.remove jar

shadowJar {
  manifest {
    attributes 'Main-Class': 'MyGroovyScriptName'
  }

  classifier = ""
}

the uber jar will be generated in the build/libs directory.