org.unix4j.variable

Class Arg

java.lang.Object

org.unix4j.variable.Arg

public class Arg
extends Object

The Arg class defines variable name constants for command arguments.

Field Summary

Fields

Modifier and Type	Field and Description
static String	$0 Name for the variable referring to the first command line argument (zero based index)
static String	$1 Name for the variable referring to the second command line argument (zero based index)
static String	$2 Name for the variable referring to the third command line argument (zero based index)
static String	$3 Name for the variable referring to the fourth command line argument (zero based index)
static String	$4 Name for the variable referring to the fifth command line argument (zero based index)
static String	$5 Name for the variable referring to the sixth command line argument (zero based index)
static String	$6 Name for the variable referring to the seventh command line argument (zero based index)
static String	$7 Name for the variable referring to the eighth command line argument (zero based index)
static String	$8 Name for the variable referring to the ninth command line argument (zero based index)
static String	$9 Name for the variable referring to the tenth command line argument (zero based index)
static String	$all Name for the variable referring to all command line arguments.

Method Summary

Methods

Modifier and Type	Method and Description
static String	arg(int i) Name for the variable referring to the (i+1)th command line argument (the index i is zero based).
static int	argIndex(String name) Returns the zero based index of an arg variable given the name of the variable.
static String	args() Name for the variable referring to all command line arguments.
static String	argsFrom(int index) Name for the variable referring to all command line arguments starting from the specified index.
static int	argsFromIndex(String name) Returns the zero based start index of an args variable given the name of the variable.
static boolean	isVariable(String expression) Returns true if and only if the given name starts with the "$" prefix.

Methods inherited from class java.lang.Object

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

Field Detail

$0

public static final String $0

Name for the variable referring to the first command line argument (zero based index)

$1

public static final String $1

Name for the variable referring to the second command line argument (zero based index)

$2

public static final String $2

Name for the variable referring to the third command line argument (zero based index)

$3

public static final String $3

Name for the variable referring to the fourth command line argument (zero based index)

$4

public static final String $4

Name for the variable referring to the fifth command line argument (zero based index)

$5

public static final String $5

Name for the variable referring to the sixth command line argument (zero based index)

$6

public static final String $6

Name for the variable referring to the seventh command line argument (zero based index)

$7

public static final String $7

Name for the variable referring to the eighth command line argument (zero based index)

$8

public static final String $8

Name for the variable referring to the ninth command line argument (zero based index)

$9

public static final String $9

Name for the variable referring to the tenth command line argument (zero based index)

$all

public static final String $all

Name for the variable referring to all command line arguments.

See Also:

Constant Field Values

Method Detail

arg

public static final String arg(int i)

Name for the variable referring to the (i+1)th command line argument (the index i is zero based).

Parameters:

i - zero based argument index

Returns:

variable name for the (i+1)th command line argument

isVariable

public static boolean isVariable(String expression)

Returns true if and only if the given name starts with the "$" prefix.

Parameters:

expression - the potential variable name to check

Returns:

if the first character of expression is a "$" character

argIndex

public static int argIndex(String name)

Returns the zero based index of an arg variable given the name of the variable. This method is the antipode of the #arg(int) method, it returns -1 if the given name is not compatible with the name returned by arg(int).

Parameters:

name - the name of the variable, such as "$0", "$1" etc.

Returns:

the index of the argument referenced by the variable, for instance 0 for the name "$0"

argsFromIndex

public static int argsFromIndex(String name)

Returns the zero based start index of an args variable given the name of the variable. This method is the antipode of the #argsFrom(int) method, it returns -1 if the given name is not compatible with the name returned by argsFrom(int).

Parameters:

name - the name of the variable, such as "$@+1", "$@+3" etc.

Returns:

the index of the argument referenced by the variable, for instance 1 for the name "$@+1"

args

public static final String args()

Name for the variable referring to all command line arguments.

Returns:

$all

argsFrom

public static final String argsFrom(int index)

Name for the variable referring to all command line arguments starting from the specified index.

Parameters:

index - zero based index of first argument in the args list

Returns:

variable name for the (index+1)th command line argument followed by all other arguments