org.wso2.balana.cond

Class ExpressionHandler

java.lang.Object

org.wso2.balana.cond.ExpressionHandler

public class ExpressionHandler
extends Object

This is a package-private utility class that handles parsing all the possible expression types. It was added becuase in 2.0 multiple classes needed this. Note that this could also be added to Expression and that interface could be made an abstract class, but that would require substantial change.

Since:

2.0

Author:

Seth Proctor

Constructor Summary

Constructors

Constructor and Description
ExpressionHandler()

Method Summary

Modifier and Type	Method and Description
static Function	getFunction(Node root, PolicyMetaData metaData, FunctionFactory factory) Helper method that tries to get a function instance
static Expression	parseExpression(Node root, PolicyMetaData metaData, VariableManager manager) Parses an expression, recursively handling any sub-elements.

Methods inherited from class java.lang.Object

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

Constructor Detail

ExpressionHandler

public ExpressionHandler()

Method Detail

parseExpression

public static Expression parseExpression(Node root,
                                         PolicyMetaData metaData,
                                         VariableManager manager)
                                  throws ParsingException

Parses an expression, recursively handling any sub-elements. This is provided as a utility class, but in practice is used only by Apply, Condition, and VariableDefinition.

Parameters:

root - the DOM root of an ExpressionType XML type

metaData - the meta-data associated with the containing policy

manager - VariableManager used to connect references and definitions while parsing

Returns:

an Expression or null if the root node cannot be parsed as a valid Expression

Throws:

ParsingException

getFunction

public static Function getFunction(Node root,
                                   PolicyMetaData metaData,
                                   FunctionFactory factory)
                            throws ParsingException

Helper method that tries to get a function instance

Throws:

ParsingException