org.jaxen.function

Class SubstringBeforeFunction

java.lang.Object

org.jaxen.function.SubstringBeforeFunction

All Implemented Interfaces:

Function

public class SubstringBeforeFunction
extends Object
implements Function

4.2 string substring-before(string,string)

The substring-before function returns the substring of the first argument string that precedes the first occurrence of the second argument string in the first argument string, or the empty string if the first argument string does not contain the second argument string. For example, substring-before("1999/04/01","/") returns 1999.

Author:

bob mcwhirter (bob @ werken.com)

See Also:

Section 4.2 of the XPath Specification

Constructor Summary

Constructors

Constructor and Description
SubstringBeforeFunction() Create a new SubstringBeforeFunction object.

Method Summary

Modifier and Type	Method and Description
Object	call(Context context, List args) Returns the part of the string-value of the first item in args that comes before the string-value of the second item in args; or the empty string if the second string is not a substring of the first string.
static String	evaluate(Object strArg, Object matchArg, Navigator nav) Returns the part of strArg that precedes the first occurence of matchArg; or the empty string if the strArg does not contain matchArg

Methods inherited from class java.lang.Object

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

Constructor Detail

SubstringBeforeFunction

public SubstringBeforeFunction()

Create a new SubstringBeforeFunction object.

Method Detail

call

public Object call(Context context,
                   List args)
            throws FunctionCallException

Returns the part of the string-value of the first item in args that comes before the string-value of the second item in args; or the empty string if the second string is not a substring of the first string.

Specified by:

call in interface Function

Parameters:

context - the context at the point in the expression when the function is called

args - a list that contains two items

Returns:

a String containing that part of the string-value of the first item in args that comes before the string-value of the second item in args

Throws:

FunctionCallException - if args does not have length two

evaluate

public static String evaluate(Object strArg,
                              Object matchArg,
                              Navigator nav)

Returns the part of strArg that precedes the first occurence of matchArg; or the empty string if the strArg does not contain matchArg

Parameters:

strArg - the string from which the substring is extracted

matchArg - the string that marks the boundary of the substring

nav - the Navigator used to calculate the string-values of the first two arguments

Returns:

a String containing the part of strArg that precedes the first occurence of matchArg