org.wso2.balana.cond

Class FunctionBase

java.lang.Object

org.wso2.balana.cond.FunctionBase

All Implemented Interfaces:

Expression, Function

Direct Known Subclasses:

AbsFunction, AddFunction, BagFunction, ComparisonFunction, DateMathFunction, DivideFunction, EqualFunction, FloorFunction, IPInRangeFunction, LogicalFunction, MatchFunction, ModFunction, MultiplyFunction, NOfFunction, NotFunction, NumericConvertFunction, RoundFunction, SetFunction, StringComparingFunction, StringConversionFunction, StringCreationFunction, StringFunction, StringNormalizeFunction, SubStringFunction, SubtractFunction, TimeInRangeFunction, URLStringCatFunction, XPathFunction

public abstract class FunctionBase
extends Object
implements Function

An abstract utility superclass for functions. Supplies several useful methods, making it easier to implement a Function. You can extend this class or implement Function directly, depending on your needs.

Since:

1.0

Author:

Steve Hanna, Seth Proctor

Field Summary

Fields

Modifier and Type	Field and Description
static String	FUNCTION_NS The standard namespace where all XACML 1.0 spec-defined functions live
static String	FUNCTION_NS_2 The standard namespace where all XACML 2.0 spec-defined functions live
static String	FUNCTION_NS_3 The standard namespace where all XACML 3.0 spec-defined functions live

Constructor Summary

Constructors

Constructor and Description
FunctionBase(String functionName, int functionId, String[] paramTypes, boolean[] paramIsBag, String returnType, boolean returnsBag) Constructor that sets up the function as having different types for each given parameter.
FunctionBase(String functionName, int functionId, String returnType, boolean returnsBag) Constructor that sets up some basic values for functions that will take care of parameter checking on their own.
FunctionBase(String functionName, int functionId, String paramType, boolean paramIsBag, int numParams, int minParams, String returnType, boolean returnsBag) Constructor that sets up the function as having some number of parameters all of the same given type.
FunctionBase(String functionName, int functionId, String paramType, boolean paramIsBag, int numParams, String returnType, boolean returnsBag) Constructor that sets up the function as having some number of parameters all of the same given type.

Method Summary

Modifier and Type	Method and Description
void	checkInputs(List inputs) Default handling of input checking.
void	checkInputsNoBag(List inputs) Default handling of input checking.
String	encode() Encodes this FunctionBase into its XML form
void	encode(StringBuilder builder) Encodes this FunctionBase into its XML form and writes this out to the provided StringBuilder
protected EvaluationResult	evalArgs(List<Evaluatable> params, EvaluationCtx context, AttributeValue[] args) Evaluates each of the parameters, in order, filling in the argument array with the resulting values.
int	getFunctionId() Returns the Identifier of the function to be handled by this particular object.
String	getFunctionName() Returns the name of the function to be handled by this particular object.
URI	getIdentifier() Returns the full identifier of this function, as known by the factories.
URI	getReturnType() Get the attribute type returned by this function.
String	getReturnTypeAsString() Returns the return type for this particular object.
URI	getType() Returns the same value as getReturnType.
protected static EvaluationResult	makeProcessingError(String message) Create an EvaluationResult that indicates a processing error with the specified message.
boolean	returnsBag() Returns true if this function returns a bag of values.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.wso2.balana.cond.Function

evaluate

Field Detail

FUNCTION_NS

public static final String FUNCTION_NS

The standard namespace where all XACML 1.0 spec-defined functions live

See Also:

Constant Field Values

FUNCTION_NS_2

public static final String FUNCTION_NS_2

The standard namespace where all XACML 2.0 spec-defined functions live

See Also:

Constant Field Values

FUNCTION_NS_3

public static final String FUNCTION_NS_3

The standard namespace where all XACML 3.0 spec-defined functions live

See Also:

Constant Field Values

Constructor Detail

FunctionBase

public FunctionBase(String functionName,
                    int functionId,
                    String paramType,
                    boolean paramIsBag,
                    int numParams,
                    String returnType,
                    boolean returnsBag)

Constructor that sets up the function as having some number of parameters all of the same given type. If numParams is -1, then the length is variable

Parameters:

functionName - the name of this function as used by the factory and any XACML policies

functionId - an optional identifier that can be used by your code for convenience

paramType - the type of all parameters to this function, as used by the factory and any XACML documents

paramIsBag - whether or not every parameter is actually a bag of values

numParams - the number of parameters required by this function, or -1 if any number are allowed

returnType - the type returned by this function, as used by the factory and any XACML documents

returnsBag - whether or not this function returns a bag of values

FunctionBase

public FunctionBase(String functionName,
                    int functionId,
                    String paramType,
                    boolean paramIsBag,
                    int numParams,
                    int minParams,
                    String returnType,
                    boolean returnsBag)

Constructor that sets up the function as having some number of parameters all of the same given type. If numParams is -1, then the length is variable, and then minParams may be used to specify a minimum number of parameters. If numParams is not -1, then minParams is ignored.

Parameters:

functionName - the name of this function as used by the factory and any XACML policies

functionId - an optional identifier that can be used by your code for convenience

paramType - the type of all parameters to this function, as used by the factory and any XACML documents

paramIsBag - whether or not every parameter is actually a bag of values

numParams - the number of parameters required by this function, or -1 if any number are allowed

minParams - the minimum number of parameters required if numParams is -1

returnType - the type returned by this function, as used by the factory and any XACML documents

returnsBag - whether or not this function returns a bag of values

FunctionBase

public FunctionBase(String functionName,
                    int functionId,
                    String[] paramTypes,
                    boolean[] paramIsBag,
                    String returnType,
                    boolean returnsBag)

Constructor that sets up the function as having different types for each given parameter.

Parameters:

functionName - the name of this function as used by the factory and any XACML policies

functionId - an optional identifier that can be used by your code for convenience

paramTypes - the type of each parameter, in order, required by this function, as used by the factory and any XACML documents

paramIsBag - whether or not each parameter is actually a bag of values

returnType - the type returned by this function, as used by the factory and any XACML documents

returnsBag - whether or not this function returns a bag of values

FunctionBase

public FunctionBase(String functionName,
                    int functionId,
                    String returnType,
                    boolean returnsBag)

Constructor that sets up some basic values for functions that will take care of parameter checking on their own. If you use this constructor for your function class, then you must override the two check methods to make sure that parameters are correct.

Parameters:

functionName - the name of this function as used by the factory and any XACML policies

functionId - an optional identifier that can be used by your code for convenience

returnType - the type returned by this function, as used by the factory and any XACML documents

returnsBag - whether or not this function returns a bag of values

Method Detail

getIdentifier

public URI getIdentifier()

Returns the full identifier of this function, as known by the factories.

Specified by:

getIdentifier in interface Function

Returns:

the function's identifier

Throws:

IllegalArgumentException - if the identifier isn't a valid URI

getFunctionName

public String getFunctionName()

Returns the name of the function to be handled by this particular object.

Returns:

the function name

getFunctionId

public int getFunctionId()

Returns the Identifier of the function to be handled by this particular object.

Returns:

the function Id

getType

public URI getType()

Returns the same value as getReturnType. This is here to support the Expression interface.

Specified by:

getType in interface Expression

Returns:

the return type

getReturnType

public URI getReturnType()

Get the attribute type returned by this function.

Specified by:

getReturnType in interface Function

Returns:

a URI indicating the attribute type returned by this function

returnsBag

public boolean returnsBag()

Returns true if this function returns a bag of values.

Specified by:

returnsBag in interface Expression

Specified by:

returnsBag in interface Function

Returns:

true if the function returns a bag, false otherwise

getReturnTypeAsString

public String getReturnTypeAsString()

Returns the return type for this particular object.

Returns:

the return type

makeProcessingError

protected static EvaluationResult makeProcessingError(String message)

Create an EvaluationResult that indicates a processing error with the specified message. This method may be useful to subclasses.

Parameters:

message - a description of the error (null if none)

Returns:

the desired EvaluationResult

evalArgs

protected EvaluationResult evalArgs(List<Evaluatable> params,
                                    EvaluationCtx context,
                                    AttributeValue[] args)

Evaluates each of the parameters, in order, filling in the argument array with the resulting values. If any error occurs, this method returns the error, otherwise null is returned, signalling that evaluation was successful for all inputs, and the resulting argument list can be used.

Parameters:

params - a List of Evaluatable objects representing the parameters to evaluate

context - the representation of the request

args - an array as long as the params List that will, on return, contain the AttributeValues generated from evaluating all parameters

Returns:

null if no errors were encountered, otherwise an EvaluationResult representing the error

checkInputs

public void checkInputs(List inputs)
                 throws IllegalArgumentException

Default handling of input checking. This does some simple checking based on the type of constructor used. If you need anything more complex, or if you used the simple constructor, then you must override this method.

Specified by:

checkInputs in interface Function

Parameters:

inputs - a List> of Evaluatables

Throws:

IllegalArgumentException - if the inputs won't work

checkInputsNoBag

public void checkInputsNoBag(List inputs)
                      throws IllegalArgumentException

Default handling of input checking. This does some simple checking based on the type of constructor used. If you need anything more complex, or if you used the simple constructor, then you must override this method.

Specified by:

checkInputsNoBag in interface Function

Parameters:

inputs - a List> of Evaluatables

Throws:

IllegalArgumentException - if the inputs won't work

encode

public String encode()

Encodes this FunctionBase into its XML form

Specified by:

encode in interface Function

Returns:

String

encode

public void encode(StringBuilder builder)

Encodes this FunctionBase into its XML form and writes this out to the provided StringBuilder

Specified by:

encode in interface Expression

Specified by:

encode in interface Function

Parameters:

builder - string stream into which the XML-encoded data is written