tambapps/groovexec

Script to execute Groovy JARs without Groovy SDK in them

groovexec: Execute JARs without Groovy SDK in them

Why groovexec

Groovy can be used for scripting, but sometimes you need more than one class, and then your script turns into a project. To execute a Groovy project (without an IDE), you would have to compile it. You could compile the jar, including all the Groovy dependencies (groovy-all or specific dependencies like groovy-json) and then launch java -jar my-groovy-project.jar but these jar can be quite heavy, as they include the whole Groovy SDK (at least the core of groovy).

If you installed Groovy on your computer, you already have the Groovy SDK. So why bother including it in your project's jar, making it heavier? Just build a jar containing only your compiled source code (and your other non-Groovy dependencies if any) and then execute it using your installed Groovy SDK.

groovexec helps you execute such jars, relying on the Groovy SDK installed in your computer.

How to use

Here is the usage of the script

usage: groovexec [options] /path/to/jar [jar arguments]
 -D,--define <arg>       (Optional) Define a system property (can be used
                         many times)
 -m,--main-class <arg>   (Optional) The main class to use. Will try to
                         guess it using the main attribute 'Main-Class'
                         from the jar's manifest if not provided

If you are on Linux, you can install it with the install.sh script. It will put the script under the /bin directory of you groovy installation.

Examples

Will try to find a main class in the jar

groovexec jar-without-groovy-sdk.jar --my-project-arg 123

Or, if you want to explicitly specify the main class

# Specifying the main class and some java system properties
groovexec -m my.groovy.project.Main jar-without-groovy-sdk.jar --my-project-arg 123

You can also define some Java System properties

# Specifying the main class and some java system properties
groovexec -D propert1=value1 -D property2=value2 jar-without-groovy-sdk.jar --my-project-arg 123

Note that if you don't want to install the groovexec, you could just execute the script with groovy.

Use

groovy groovexec.groovy args...

Instead of

groovexec args...

Excluding Groovy SDK from your JARs

To make your JAR smaller, you would have to exclude Groovy SDK when building it.

In Gradle projects

Use the compileOnly for all your Groovy dependencies (actually I haven't tested this as I am a Maven guy, so if it doesn't work please, notify me)

E.g.

compileOnly group: 'org.apache.groovy', name: 'groovy-all', version: '4.0.3', ext: 'pom'
compileOnly group: 'org.apache.groovy', name: 'groovy-cli-commons', version: '4.0.3'

In Maven projects

Add the provided scope to all your Groovy dependencies

E.g.

<dependencies>
  <dependency>
    <groupId>org.apache.groovy</groupId>
    <artifactId>groovy-all</artifactId>
    <version>4.0.3</version>
    <type>pom</type>
  </dependency>
  <dependency>
    <groupId>org.apache.groovy</groupId>
    <artifactId>groovy-cli-commons</artifactId>
    <version>4.0.3</version>
    <scope>provided</scope>
  </dependency>
</dependencies>