org.apache.wicket.application

Class WildcardMatcherHelper

java.lang.Object

org.apache.wicket.application.WildcardMatcherHelper

public class WildcardMatcherHelper
extends Object

This class is an utility class that perform wildcard-patterns matching and isolation.

Version:

$Id: WildcardMatcherHelper.java 420832 2006-07-11 13:11:02Z cziegeler $

Field Summary

Fields

Modifier and Type	Field and Description
static char	ESC Escape character
static char	PATHSEP Default path separator: "."
static char	STAR any char

Constructor Summary

Constructors

Constructor and Description
WildcardMatcherHelper()

Method Summary

Modifier and Type	Method and Description
static Map<String,String>	match(String pat, String str) Match a pattern against a string and isolates wildcard replacement into a Map.

Methods inherited from class java.lang.Object

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

Field Detail

ESC

public static final char ESC

Escape character

See Also:

Constant Field Values

PATHSEP

public static final char PATHSEP

Default path separator: "."

See Also:

Constant Field Values

STAR

public static final char STAR

any char

See Also:

Constant Field Values

Constructor Detail

WildcardMatcherHelper

public WildcardMatcherHelper()

Method Detail

match

public static Map<String,String> match(String pat,
                                       String str)

Match a pattern against a string and isolates wildcard replacement into a Map.
Here is how the matching algorithm works:

• The '*' character, meaning that zero or more characters (excluding the path separator '/') are to be matched.
• The '**' sequence, meaning that zero or more characters (including the path separator '/') are to be matched.
• The '\*' sequence is honored as a literal '*' character, not a wildcard

When more than two '*' characters, not separated by another character, are found their value is considered as '**' and immediate succeeding '*' are skipped.
The '**' wildcard is greedy and thus the following sample cannot match:

pattern

STAR,STAR,PATHSEP,STAR,PATHSEP,STAR,STAR (why can't I express it literally?)

string

foo/bar/baz/bug

The first '**' in the pattern will suck up until the last '/' in string and thus will not match.
A more advance algorithm could certainly check whether there is an other literal later in the pattern to ev. match in string but I'll leave this exercise to someone else ATM if one needs such.

Parameters:

pat - The pattern string.

str - The string to math against the pattern

Returns:

a Map containing the representation of the extracted pattern. The extracted patterns are keys in the Map from left to right beginning with "1" for the left most, "2" for the next, a.s.o. The key "0" is the string itself. If the return value is null, string does not match to the pattern .