org.conqat.lib.commons.options

Class CommandLine

java.lang.Object

org.conqat.lib.commons.options.CommandLine

public class CommandLine
extends java.lang.Object

A class providing command line parsing and usage messages using GNU syntax.

The GNU syntax is implemented as follows. There are short (single character) and long (multi character) options, just as provided by the AOption annotation. Short options are introduced using a single minus (e.g. '-h') while long options are introduced using a double minus (e.g. '--help'). The parameter for an option is either the next argument, or--in case of long options--possibly separated by an equals sign (e.g. '--file=test.txt'). Short options may be chained (e.g. '-xvf abc' instead of '-x -v -f abc'). For chained short options, only the last option may take a parameter. The separator '--' may be used to switch off argument processing for the remaining arguments, i.e. all other arguments are treated as left-overs.

Constructor Summary

Constructors

Constructor and Description
CommandLine(OptionRegistry registry) Constructor.

Method Summary

Modifier and Type	Method and Description
java.lang.String[]	parse(CommandLineTokenStream ts) Parses the command line parameters implicitly given by the token stream and applies the options found.
java.lang.String[]	parse(java.lang.String[] args) Parses the given command line parameters and applies the options found.
void	printUsage(java.io.PrintWriter pw) Print the list of all supported options using reasonable default values for widths.
void	printUsage(java.io.PrintWriter pw, int firstCol, int width) Print the list of all supported options.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CommandLine

public CommandLine(OptionRegistry registry)

Constructor.

Parameters:

registry - Registry containing the options to be used by this instance.

Method Detail

parse

public java.lang.String[] parse(java.lang.String[] args)
                         throws OptionException

Parses the given command line parameters and applies the options found. The arguments not treated as options or parameters are returned (often they are treated as file arguments). If the syntax does not conform to the options in the registry, an OptionException is thrown.

Parameters:

args - the command line arguments to be parsed.

Returns:

the remaining arguments.

Throws:

OptionException - in case of syntax errors or invalid parameters.

parse

public java.lang.String[] parse(CommandLineTokenStream ts)
                         throws OptionException

Parses the command line parameters implicitly given by the token stream and applies the options found. The arguments not treated as options or parameters are returned (often they are treated as file arguments). If the syntax does not conform to the options in the registry an IllegalArgumentException is thrown.

Parameters:

ts - Token stream containing the arguments.

Returns:

Remaining arguments.

Throws:

OptionException - in case of syntax errors or invalid parameters.

printUsage

public void printUsage(java.io.PrintWriter pw)

Print the list of all supported options using reasonable default values for widths.

Parameters:

pw - the writer used for output.

printUsage

public void printUsage(java.io.PrintWriter pw,
                       int firstCol,
                       int width)

Print the list of all supported options.

Parameters:

pw - the writer to print to.

firstCol - the width of the first column containing the option name (without the trailing space).

width - the maximal width of a line (aka terminal width).