Airline
Airline is a Java annotation-based framework for parsing Git like command line structures.
Latest release is 0.8, available from Maven Central.
<dependency>
<groupId>io.airlift</groupId>
<artifactId>airline</artifactId>
<version>0.8</version>
</dependency>
Here is a quick example:
public class Git
{
public static void main(String[] args)
{
CliBuilder<Runnable> builder = Cli.<Runnable>builder("git")
.withDescription("the stupid content tracker")
.withDefaultCommand(Help.class)
.withCommands(Help.class, Add.class);
builder.withGroup("remote")
.withDescription("Manage set of tracked repositories")
.withDefaultCommand(RemoteShow.class)
.withCommands(RemoteShow.class, RemoteAdd.class);
Cli<Runnable> gitParser = builder.build();
gitParser.parse(args).run();
}
public static class GitCommand implements Runnable
{
@Option(type = OptionType.GLOBAL, name = "-v", description = "Verbose mode")
public boolean verbose;
public void run()
{
System.out.println(getClass().getSimpleName());
}
}
@Command(name = "add", description = "Add file contents to the index")
public static class Add extends GitCommand
{
@Arguments(description = "Patterns of files to be added")
public List<String> patterns;
@Option(name = "-i", description = "Add modified contents interactively.")
public boolean interactive;
}
@Command(name = "show", description = "Gives some information about the remote <name>")
public static class RemoteShow extends GitCommand
{
@Option(name = "-n", description = "Do not query remote heads")
public boolean noQuery;
@Arguments(description = "Remote to show")
public String remote;
}
@Command(name = "add", description = "Adds a remote")
public static class RemoteAdd extends GitCommand
{
@Option(name = "-t", description = "Track only a specific branch")
public String branch;
@Arguments(description = "Remote repository to add")
public List<String> remote;
}
}
Assuming you have packaged this as an executable program named 'git', you would be able to execute the following commands:
$ git add -p file
$ git remote add origin [email protected]:airlift/airline.git
$ git -v remote show origin
Single Command Mode
Airline can also be used for simple, single-command programs:
@Command(name = "ping", description = "network test utility")
public class Ping
{
@Inject
public HelpOption helpOption;
@Option(name = {"-c", "--count"}, description = "Send count packets")
public int count = 1;
public static void main(String... args)
{
Ping ping = SingleCommand.singleCommand(Ping.class).parse(args);
if (ping.helpOption.showHelpIfRequested()) {
return;
}
ping.run();
}
public void run()
{
System.out.println("Ping count: " + count);
}
}
Assuming you have packaged this as an executable program named 'ping', you would be able to execute the following commands:
$ ping
$ ping -c 5
$ ping --help
Help System
Airline contains a fully automated help system, which generates man-page-like documentation driven by the Java annotations.
As you may have noticed in the git code above, we added Help.class
to the cli. This command is provided by Airline and works as follows:
$ git help
usage: git [-v] <command> [<args>]
The most commonly used git commands are:
add Add file contents to the index
help Display help information
remote Manage set of tracked repositories
See 'git help <command>' for more information on a specific command.
$ git help git
NAME
git - the stupid content tracker
SYNOPSIS
git [-v] <command> [<args>]
OPTIONS
-v
Verbose mode
COMMANDS
help
Display help information
add
Add file contents to the index
remote show
Gives some information about the remote <name>
remote add
Adds a remote
$ git help add
NAME
git add - Add file contents to the index
SYNOPSIS
git [-v] add [-i] [--] [<patterns>...]
OPTIONS
-i
Add modified contents interactively.
-v
Verbose mode
--
This option can be used to separate command-line options from the
list of argument, (useful when arguments might be mistaken for
command-line options
<patterns>
Patterns of files to be added
$ git help remote
NAME
git remote - Manage set of tracked repositories
SYNOPSIS
git [-v] remote
git [-v] remote add [-t <branch>]
git [-v] remote show [-n]
OPTIONS
-v
Verbose mode
COMMANDS
With no arguments, Gives some information about the remote <name>
show
Gives some information about the remote <name>
With -n option, Do not query remote heads
add
Adds a remote
With -t option, Track only a specific branch
$ git help remote show
NAME
git remote show - Gives some information about the remote <name>
SYNOPSIS
git [-v] remote show [-n] [--] [<remote>]
OPTIONS
-n
Do not query remote heads
-v
Verbose mode
--
This option can be used to separate command-line options from the
list of argument, (useful when arguments might be mistaken for
command-line options
<remote>
Remote to show
We have also, add Help.class
as the default command for git, so if you execute git without any arguments, you will see the following:
$ git help
usage: git [-v] <command> [<args>]
The most commonly used git commands are:
add Add file contents to the index
help Display help information
remote Manage set of tracked repositories
See 'git help <command>' for more information on a specific command.
For simple, single-command programs like ping, use the HelpOption
option as shown in the example above. HelpOption
handles the options -h
and --help
and provides the showHelpIfRequested()
method to automatically show the following help output:
$ ping -h
NAME
ping - network test utility
SYNOPSIS
ping [(-c <count> | --count <count>)] [(-h | --help)]
OPTIONS
-c <count>, --count <count>
Send count packets
-h, --help
Display help information