org.apache.commons.jxpath.ri.compiler
Class ExtensionFunction

java.lang.Object
  |
  +--org.apache.commons.jxpath.ri.compiler.Expression
        |
        +--org.apache.commons.jxpath.ri.compiler.Operation
              |
              +--org.apache.commons.jxpath.ri.compiler.ExtensionFunction

public class ExtensionFunction
extends Operation

Represents an element of the parse tree representing an extension function call.

Version:
$Revision: 1.5 $ $Date: 2002/05/08 00:39:59 $
Author:
Dmitri Plotnikov

Nested Class Summary
 
Nested classes inherited from class org.apache.commons.jxpath.ri.compiler.Expression
Expression.PointerIterator, Expression.ValueIterator
 
Field Summary
 
Fields inherited from class org.apache.commons.jxpath.ri.compiler.Operation
args
 
Fields inherited from class org.apache.commons.jxpath.ri.compiler.Expression
NaN, ONE, OP_AND, OP_CONSTANT, OP_CORE_FUNCTION, OP_DIV, OP_EQ, OP_EXPRESSION_PATH, OP_FUNCTION, OP_GT, OP_GTE, OP_KEY_LOOKUP, OP_LOCATION_PATH, OP_LT, OP_LTE, OP_MINUS, OP_MOD, OP_MULT, OP_NE, OP_OR, OP_STEP, OP_SUM, OP_UNARY_MINUS, OP_UNION, OP_VAR, ZERO
 
Constructor Summary
ExtensionFunction(QName functionName, Expression[] args)
           
 
Method Summary
 java.lang.Object compute(EvalContext context)
           
 boolean computeContextDependent()
          An extension function gets the current context, therefore it MAY be context dependent.
 java.lang.Object computeValue(EvalContext context)
          Evaluates the expression.
 QName getFunctionName()
           
 java.lang.String opCodeToString()
           
 
Methods inherited from class org.apache.commons.jxpath.ri.compiler.Operation
getArguments
 
Methods inherited from class org.apache.commons.jxpath.ri.compiler.Expression
getExpressionTypeCode, isContextDependent, iterate, iteratePointers, toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

ExtensionFunction

public ExtensionFunction(QName functionName,
                         Expression[] args)
Method Detail

getFunctionName

public QName getFunctionName()

computeContextDependent

public boolean computeContextDependent()
An extension function gets the current context, therefore it MAY be context dependent.

Overrides:
computeContextDependent in class Operation

opCodeToString

public java.lang.String opCodeToString()
Overrides:
opCodeToString in class Expression

compute

public java.lang.Object compute(EvalContext context)
Specified by:
compute in class Expression

computeValue

public java.lang.Object computeValue(EvalContext context)
Description copied from class: Expression
Evaluates the expression. If the result is a node set, returns the first element of the node set.

Specified by:
computeValue in class Expression


Copyright (c) 2001 - Apache Software Foundation