Package org.ow2.authzforce.core.pdp.api.func

Class RegexpMatchFunctionHelper

java.lang.Object

org.ow2.authzforce.core.pdp.api.func.RegexpMatchFunctionHelper

public final class RegexpMatchFunctionHelper
extends Object

*-regexp-match function helper

WARNING: the regular expression syntax required by XACML refers to the xf:matches function from [XF] (see the XACML core spec for this reference). This function and associated syntax differ from Pattern (Java 7) in several ways. Therefore, we cannot use Pattern directly. Find examples of differences below:

• Pattern matches the entire string against the pattern always, whereas xf:matches considers the string to match the pattern if any substring matches the pattern.
• xf:matches regular expression syntax is based on XML schema which defines character class substraction using '-' character, whereas Pattern does not support this syntax but &&[^ instead.
• Category escape: can be done in XML SCHEMA with: [\P{X}]. Pattern only supports this form: [^\p{X}].
• Character classes: XML schema define categories \c and \C. Pattern does not support them.

EXAMPLE: this regex from XML schema spec uses character class substraction. It is valid for xf:matches but does not compile with Pattern:

 [\i-[:]][\c-[:]]*
 

Constructor Summary

Constructors

Constructor	Description
RegexpMatchFunctionHelper(FirstOrderFunctionSignature<BooleanValue> matchFunctionSignature, Datatype<? extends SimpleValue<String>> matchedDatatype)	Creates a "regex-match" (matching regular expressions) function helper

Method Summary

Modifier and Type	Method	Description
FirstOrderFunctionCall<BooleanValue>	getCompiledRegexMatchCall(List<Expression<?>> argExpressions, Datatype<?>... remainingArgTypes)	Creates regex-match function call using pre-compiled regex
static boolean	match(StringValue regex, SimpleValue<String> arg1)	Match a string against a regular expression

Methods inherited from class java.lang.Object

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

Constructor Detail

RegexpMatchFunctionHelper

public RegexpMatchFunctionHelper(FirstOrderFunctionSignature<BooleanValue> matchFunctionSignature,
                                 Datatype<? extends SimpleValue<String>> matchedDatatype)

Creates a "regex-match" (matching regular expressions) function helper

Parameters:

matchFunctionSignature - signature of function that getCompiledRegexMatchCall(List, Datatype...) must create

matchedDatatype - datatype of value to be matched against the regular expression

Method Detail

match

public static boolean match(StringValue regex,
                            SimpleValue<String> arg1)
                     throws IllegalArgumentException

Match a string against a regular expression

Parameters:

regex - regular expression

arg1 - string value

Returns:

true iff arg1 matches regex

Throws:

IllegalArgumentException - regex is not a valid regular expression

getCompiledRegexMatchCall

public FirstOrderFunctionCall<BooleanValue> getCompiledRegexMatchCall(List<Expression<?>> argExpressions,
                                                                      Datatype<?>... remainingArgTypes)

Creates regex-match function call using pre-compiled regex

Parameters:

argExpressions - input expressions

remainingArgTypes - types of remaining arguments (after input expressions)

Returns:

function call using compiled regex from first argument if constant value; or null if first argument is not constant