Package org.apache.xpath.functions
Class FuncExtFunction
java.lang.Object
org.apache.xpath.Expression
org.apache.xpath.functions.Function
org.apache.xpath.functions.FuncExtFunction
- All Implemented Interfaces:
Serializable
,SourceLocator
,ExpressionNode
,XPathVisitable
An object of this class represents an extension call expression. When
the expression executes, it calls ExtensionsTable#extFunction, and then
converts the result to the appropriate XObject.
- See Also:
-
Constructor Summary
ConstructorsConstructorDescriptionFuncExtFunction
(String namespace, String extensionName, Object methodKey) Create a new FuncExtFunction based on the qualified name of the extension, and a unique method key. -
Method Summary
Modifier and TypeMethodDescriptionvoid
callArgVisitors
(XPathVisitor visitor) Call the visitors for the function arguments.void
checkNumberArgs
(int argNum) Check that the number of arguments passed to this function is correct.execute
(XPathContext xctxt) Execute the function.void
Set the parent node.void
fixupVariables
(Vector vars, int globalsSize) This function is used to fixup variables from QNames to stack frame indexes at stylesheet build time.getArg
(int n) Return the nth argument passed to the extension function.int
Return the number of arguments that were passed into this extension function.Return the name of the extension function.Return the method key of the extension function.Return the namespace of the extension function.void
setArg
(Expression arg, int argNum) Set an argument expression for a function.toString()
Return the name of the extesion function in string formatMethods inherited from class org.apache.xpath.functions.Function
callVisitors, deepEquals, postCompileStep
Methods inherited from class org.apache.xpath.Expression
asIterator, asIteratorRaw, asNode, assertion, bool, canTraverseOutsideSubtree, error, execute, execute, execute, executeCharsToContentHandler, exprAddChild, exprGetChild, exprGetNumChildren, exprGetParent, getColumnNumber, getExpressionOwner, getLineNumber, getPublicId, getSystemId, isNodesetExpr, isStableNumber, num, warn, xstr
-
Constructor Details
-
FuncExtFunction
Create a new FuncExtFunction based on the qualified name of the extension, and a unique method key.- Parameters:
namespace
- The namespace for the extension function, which should not normally be null or empty.extensionName
- The local name of the extension.methodKey
- Unique method key, which is passed to ExtensionsTable#extFunction in order to allow caching of the method.
-
-
Method Details
-
fixupVariables
This function is used to fixup variables from QNames to stack frame indexes at stylesheet build time.- Specified by:
fixupVariables
in classExpression
- Parameters:
vars
- List of QNames that correspond to variables. This list should be searched backwards for the first qualified name that corresponds to the variable reference qname. The position of the QName in the vector from the start of the vector will be its position in the stack frame (but variables above the globalsTop value will need to be offset to the current stack frame). NEEDSDOC @param globalsSize
-
getNamespace
Return the namespace of the extension function.- Returns:
- The namespace of the extension function.
-
getFunctionName
Return the name of the extension function.- Returns:
- The name of the extension function.
-
getMethodKey
Return the method key of the extension function.- Returns:
- The method key of the extension function.
-
getArg
Return the nth argument passed to the extension function.- Parameters:
n
- The argument number index.- Returns:
- The Expression object at the given index.
-
getArgCount
public int getArgCount()Return the number of arguments that were passed into this extension function.- Returns:
- The number of arguments.
-
execute
Execute the function. The function must return a valid object.- Overrides:
execute
in classFunction
- Parameters:
xctxt
- The current execution context.- Returns:
- A valid XObject.
- Throws:
TransformerException
-
setArg
Set an argument expression for a function. This method is called by the XPath compiler.- Overrides:
setArg
in classFunction
- Parameters:
arg
- non-null expression that represents the argument.argNum
- The argument number index.- Throws:
WrongNumberArgsException
- If the argNum parameter is beyond what is specified for this function.
-
checkNumberArgs
Check that the number of arguments passed to this function is correct.- Overrides:
checkNumberArgs
in classFunction
- Parameters:
argNum
- The number of arguments that is being passed to the function.- Throws:
WrongNumberArgsException
-
callArgVisitors
Call the visitors for the function arguments.- Overrides:
callArgVisitors
in classFunction
-
exprSetParent
Set the parent node. For an extension function, we also need to set the parent node for all argument expressions.- Specified by:
exprSetParent
in interfaceExpressionNode
- Overrides:
exprSetParent
in classExpression
- Parameters:
n
- The parent node
-
toString
Return the name of the extesion function in string format
-