net.sf.practicalxml.xpath

Interface FunctionResolver.SelfDescribingFunction

All Superinterfaces:

Comparable<FunctionResolver.SelfDescribingFunction>, XPathFunction

All Known Implementing Classes:

AbstractFunction, AbstractStringFunction, FunctionResolver.AbstractSelfDescribingFunction, Lowercase, Uppercase, XsiBoolean

Enclosing class:

FunctionResolver

public static interface FunctionResolver.SelfDescribingFunction
extends XPathFunction, Comparable<FunctionResolver.SelfDescribingFunction>

A self-describing function: one that can describe its own name and arity, and compare itself to other self-describing functions.

Implementations must implement Comparable to allow the function resolver to pick the most appropriate instance for a specific invocation. The primary issue is with arity, so any comparator must follow these rules:

• Instances that accept fewer arguments are considered less-than instances that accept more.
• If two instances accept the same number of arguments, the instance with the lower minimum argument count is less-than that with the higher count.

Method Summary

Methods

Modifier and Type	Method and Description
int	getMaxArgCount() Returns the maximum number of arguments handled by this function.
int	getMinArgCount() Returns the minimum number of arguments handled by this function.
String	getName() Returns the name of this function.
String	getNamespaceUri() Returns the namespace URI for this function.
QName	getQName() Returns the qualified name of this function, consisting of name and namespace (but not prefix).
boolean	isArityMatch(int arity) Determines whether this function can handle the specified number of arguments.
boolean	isMatch(QName qname, int arity) Determines whether this function is a match for a call to XPathFunctionResolver.resolveFunction().

Methods inherited from interface javax.xml.xpath.XPathFunction

evaluate

Methods inherited from interface java.lang.Comparable

compareTo

Method Detail

getQName

QName getQName()

Returns the qualified name of this function, consisting of name and namespace (but not prefix).

getNamespaceUri

String getNamespaceUri()

Returns the namespace URI for this function.

getName

String getName()

Returns the name of this function.

getMinArgCount

int getMinArgCount()

Returns the minimum number of arguments handled by this function.

getMaxArgCount

int getMaxArgCount()

Returns the maximum number of arguments handled by this function.

isMatch

boolean isMatch(QName qname,
              int arity)

Determines whether this function is a match for a call to XPathFunctionResolver.resolveFunction().

isArityMatch

boolean isArityMatch(int arity)

Determines whether this function can handle the specified number of arguments.