XPathNSResolver (Java SE 12 & JDK 12 )
Keywords: org.w3c.dom.xpath.XPathNSResolver interface

Module jdk.xml.dom
Package org.w3c.dom.xpath

## Interface XPathNSResolver

-     public interface XPathNSResolver

  The `XPathNSResolver` interface permit `prefix` strings in the expression to be properly bound to `namespaceURI` strings. `XPathEvaluator` can construct an implementation of `XPathNSResolver` from a node, or the interface may be implemented by any application.

  See also the Document Object Model (DOM) Level 3 XPath Specification.

- - ### Method Summary

    Modifier and Type | Method | Description
    --- | --- | ---
    `String` | `lookupNamespaceURI​(String prefix)` | Look up the namespace URI associated to the given namespace prefix.

- - ### Method Detail

    - #### lookupNamespaceURI

          String lookupNamespaceURI​(String prefix)

      Look up the namespace URI associated to the given namespace prefix. The XPath evaluator must never call this with a `null` or empty argument, because the result of doing this is undefined.
      Parameters:
        `prefix` - The prefix to look for.
      Returns:
        Returns the associated namespace URI or `null` if none is found.