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XPathFunctionResolver
public
interface
XPathFunctionResolver
| javax.xml.xpath.XPathFunctionResolver
|
XPathFunctionResolver provides access to the set of user defined XPathFunctions.
XPath functions are resolved by name and arity.
The resolver is not needed for XPath built-in functions and the resolver
cannot be used to override those functions.
In particular, the resolver is only called for functions in an another
namespace (functions with an explicit prefix). This means that you cannot
use the XPathFunctionResolver to implement specifications
like XML-Signature Syntax
and Processing which extend the function library of XPath 1.0 in the
same namespace. This is a consequence of the design of the resolver.
If you wish to implement additional built-in functions, you will have to
extend the underlying implementation directly.
Summary
Public methods
resolveFunction
public abstract XPathFunction resolveFunction (QName functionName,
int arity)
Find a function in the set of available functions.
If functionName or arity is null, then a NullPointerException is thrown.
| Parameters |
|---|
functionName |
QName: The function name. |
arity |
int: The number of arguments that the returned function must accept. |
| Returns |
|---|
XPathFunction |
The function or null if no function named functionName with arity arguments exists. |
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Last updated 2025-02-10 UTC.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-02-10 UTC."],[],[],null,["# XPathFunctionResolver\n\nAdded in [API level 8](/guide/topics/manifest/uses-sdk-element#ApiLevels) \n\nXPathFunctionResolver\n=====================\n\n\n`\npublic\n\n\ninterface\nXPathFunctionResolver\n`\n\n\n`\n\n\n`\n\n|---------------------------------------|\n| javax.xml.xpath.XPathFunctionResolver |\n\n\u003cbr /\u003e\n\n*** ** * ** ***\n\n\u003cbr /\u003e\n\n`XPathFunctionResolver` provides access to the set of user defined `XPathFunction`s.\n\nXPath functions are resolved by name and arity.\nThe resolver is not needed for XPath built-in functions and the resolver\n***cannot*** be used to override those functions.\n\nIn particular, the resolver is only called for functions in an another\nnamespace (functions with an explicit prefix). This means that you cannot\nuse the `XPathFunctionResolver` to implement specifications\nlike [XML-Signature Syntax\nand Processing](http://www.w3.org/TR/xmldsig-core/) which extend the function library of XPath 1.0 in the\nsame namespace. This is a consequence of the design of the resolver.\n\nIf you wish to implement additional built-in functions, you will have to\nextend the underlying implementation directly.\n\n\u003cbr /\u003e\n\n**See also:**\n\n- [XML Path Language (XPath) Version 1.0, Core Function Library](http://www.w3.org/TR/xpath#corelib)\n\nSummary\n-------\n\n| ### Public methods ||\n|-----------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| ` abstract `[XPathFunction](/reference/javax/xml/xpath/XPathFunction) | ` `[resolveFunction](/reference/javax/xml/xpath/XPathFunctionResolver#resolveFunction(javax.xml.namespace.QName,%20int))`(`[QName](/reference/javax/xml/namespace/QName)` functionName, int arity) ` \u003cbr /\u003e Find a function in the set of available functions. |\n\nPublic methods\n--------------\n\n### resolveFunction\n\nAdded in [API level 8](/guide/topics/manifest/uses-sdk-element#ApiLevels) \n\n```\npublic abstract XPathFunction resolveFunction (QName functionName, \n int arity)\n```\n\n\u003cbr /\u003e\n\nFind a function in the set of available functions.\n\nIf `functionName` or `arity` is `null`, then a `NullPointerException` is thrown.\n\n\u003cbr /\u003e\n\n\u003cbr /\u003e\n\n| Parameters ||\n|----------------|-------------------------------------------------------------------------------|\n| `functionName` | `QName`: The function name. \u003cbr /\u003e |\n| `arity` | `int`: The number of arguments that the returned function must accept. \u003cbr /\u003e |\n\n| Returns ||\n|-----------------------------------------------------------|--------------------------------------------------------------------------------------------------|\n| [XPathFunction](/reference/javax/xml/xpath/XPathFunction) | The function or `null` if no function named `functionName` with `arity` arguments exists. \u003cbr /\u003e |\n\n| Throws ||\n|-------------------------------------------------------------------|-----------------------------------------|\n| [NullPointerException](/reference/java/lang/NullPointerException) | If `functionName` or `arity` is `null`. |"]]
