Airline is a Java library providing an annotation-based framework for parsing command line interfaces.

It supports both simple single commands through to complex git style interfaces with groups.

This is a substantially rewritten fork of the original airline library created based on improvements predominantly developed by myself plus some minor improvements taken from the Clark & Parsia fork.

Airline 2 contains significant breaking changes from Airline 1.x, please see Migrating.md for more details on how to migrate code forward.

Airline 2.1 contains some further minor breaking changes that should only affect advanced users, again please see Migrating.md for more details on how to migrate code forward. Some users may need to add additional Maven dependencies if they were using help formats other than the basic CLI help.

Airline 2.2 has some minor breaking changes that may affect users of the @Arguments annotation, again please see Migrating.md for more details.

We're currently working on our new website which will eventually include a comprehensive user guide though is currently a work in progress.

You can find the website at http://rvesse.github.io/airline/

To use airline you need to add a dependency to it to your own code, the Maven artifacts are described later in this file.

You then need to use the various annotations to annotate your command classes:

• @Command is used to annotate classes
• @Option is used to annotate fields to indicate they are options
• @Arguments is used to annotate fields that take in arguments
• @Inject can be used to modularise option definitions into separate classes

Please see the examples module for a range of examples that show off the many features of this library and practical examples of using the annotations.

Simply create a parser instance via SingleCommand.singleCommand() passing in a class that is annotated with the @Command annotation e.g.

public static void main(String[] args) {
    SingleCommand<YourClass> parser = SingleCommand.singleCommand(YourClass.class);
    YourClass cmd = parser.parse(args);
    
     // Execute your command however is appropriate e.g.
     cmd.run();   
}

Create an instance of a Cli, this can be done either using the CliBuilder or by annotating a class with the @Cli annotation. This is somewhat more complicated so please see the examples module for proper examples.

Note that typically you will want to create an executable JAR for your CLI using something like the Maven Shade plugin. This will then allow you to create a simple wrapper script that invokes your CLI.

#!/bin/bash
# myapp

java -jar my-app.jar "$@"

Note: You must use "$@" here as otherwise Bash may expand/interpret arguments and as a result the JVM may not receive the expected arguments that the user enters.

If this is done you can then invoke your application e.g.

 myapp --global-option command --command-option arguments

Or:

myapp --global-option group --group-option command --command-option arguments

Airline is licensed under the Apache Software License Version 2.0, see provided License.txt

See provided Notice.md for Copyright Holders

This library is available from Maven Central with the latest stable release being 2.2.0

Use the following maven dependency declaration:

<dependency>
    <groupId>com.github.rvesse</groupId>
    <artifactId>airline</artifactId>
    <version>2.2.0</version>
</dependency>

Snapshot artifacts of the latest source are also available using the version 2.3.0-SNAPSHOT from the OSSRH repositories.

CI builds are run on Travis CI , see build information and history at https://travis-ci.org/rvesse/airline