qwazr / commons-cli-annotations

Parsing command line options thru annotations

commons-cli-annotations

This library let you use annotations to parse command line arguments.

It uses the robust Apache Commons CLI in backend.

License Apache 2.0

Ant Example

The Java applications Ant will be used here to illustrate how to create the Options required.

The following is the definition of the options using the Option annotations:

import com.qwazr.cli.Option;
import java.util.Map;
import java.util.Set;

public class AntExample {

	@Option(desc = "print this message")
	boolean help;

	@Option(desc = "print project help information")
	boolean projecthelp;

	@Option(desc = "print the version information and exit")
	boolean version;

	@Option(desc = "be extra quiet")
	boolean quiet;

	@Option(desc = "be extra verbose")
	boolean verbose;

	@Option(desc = "print debugging information")
	boolean debug;

	@Option(desc = "produce logging information without adornments")
	boolean emacs;

	@Option(desc = "use given file for log", argName = "file", hasArg = true)
	String logfile;

	@Option(desc = "the class which it to perform logging", argName = "classname", hasArg = true)
	String logger;

	@Option(desc = "add an instance of class as a project listener",
			argName = "classname",
			hasArg = true,
			numberOfArgs = Option.UNLIMITED)
	Set<String> listener;

	@Option(desc = "use given buildfile", argName = "file", hasArg = true, valueSeparator = ' ')
	String buildfile;

	@Option(desc = "search for buildfile towards the root of the filesystem and use it", hasArg = true)
	String find;

	@Option(opt = "D",
			argName = "property=value",
			hasArg = true,
			numberOfArgs = 2,
			valueSeparator = '=',
			desc = "use value for given property")
	Map<String, String> properties;

}

The parse method of Parser is used to parse the command line arguments.

It returns a new "AntExample" instance and fill the properties with the detected arguments.

import com.qwazr.cli.Parser;

public class MyApplication {
	
    public static void main(String[] args) {
    	
        // Build the parser
        Parser<AntExample> parser = new Parser<>(AntExample.class);
       
        // Parse the arguments
        AntExample antExample = parser.parse(args);
        if (antExample.help)
        	parser.printHelp("ant");
    }
}

The parser can also print a formatted help message to System.out.

Here is an example of output:

usage: ant
 -buildfile <file>       use given buildfile
 -D <property=value>     use value for given property
 -debug                  print debugging information
 -emacs                  produce logging information without adornments
 -find <arg>             search for buildfile towards the root of the
                         filesystem and use it
 -help                   print this message
 -listener <classname>   add an instance of class as a project listener
 -logfile <file>         use given file for log
 -logger <classname>     the class which it to perform logging
 -projecthelp            print project help information
 -quiet                  be extra quiet
 -verbose                be extra verbose
 -version                print the version information and exit

Maven integration

 <dependency>
    <groupId>com.qwazr</groupId>
    <artifactId>commons-cli-annotations</artifactId>
    <version>1.0.1</version>
</dependency>

JAVADOC

Javadoc API documentation