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src/java.xml/share/classes/javax/xml/xpath/XPathFunctionResolver.java

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  27 
  28 import javax.xml.namespace.QName;
  29 
  30 /**
  31  * <p><code>XPathFunctionResolver</code> provides access to the set of user defined <code>XPathFunction</code>s.</p>
  32  *
  33  * <p>XPath functions are resolved by name and arity.
  34  * The resolver is not needed for XPath built-in functions and the resolver
  35  * <strong><em>cannot</em></strong> be used to override those functions.</p>
  36  *
  37  * <p>In particular, the resolver is only called for functions in an another
  38  * namespace (functions with an explicit prefix). This means that you cannot
  39  * use the <code>XPathFunctionResolver</code> to implement specifications
  40  * like <a href="http://www.w3.org/TR/xmldsig-core/">XML-Signature Syntax
  41  * and Processing</a> which extend the function library of XPath 1.0 in the
  42  * same namespace. This is a consequence of the design of the resolver.</p>
  43  *
  44  * <p>If you wish to implement additional built-in functions, you will have to
  45  * extend the underlying implementation directly.</p>
  46  *
  47  * @author  <a href="mailto:Norman.Walsh@Sun.com">Norman Walsh</a>
  48  * @author  <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
  49  * @see <a href="http://www.w3.org/TR/xpath#corelib">XML Path Language (XPath) Version 1.0, Core Function Library</a>
  50  * @since 1.5
  51  */
  52 public interface XPathFunctionResolver {
  53   /**
  54    * <p>Find a function in the set of available functions.</p>
  55    *
  56    * <p>If <code>functionName</code> or <code>arity</code> is <code>null</code>, then a <code>NullPointerException</code> is thrown.</p>
  57    *
  58    * @param functionName The function name.
  59    * @param arity The number of arguments that the returned function must accept.
  60    *
  61    * @return The function or <code>null</code> if no function named <code>functionName</code> with <code>arity</code> arguments exists.
  62    *
  63    * @throws NullPointerException If <code>functionName</code> or <code>arity</code> is <code>null</code>.
  64    */
  65   public XPathFunction resolveFunction(QName functionName, int arity);
  66 }


  27 
  28 import javax.xml.namespace.QName;
  29 
  30 /**
  31  * <p><code>XPathFunctionResolver</code> provides access to the set of user defined <code>XPathFunction</code>s.</p>
  32  *
  33  * <p>XPath functions are resolved by name and arity.
  34  * The resolver is not needed for XPath built-in functions and the resolver
  35  * <strong><em>cannot</em></strong> be used to override those functions.</p>
  36  *
  37  * <p>In particular, the resolver is only called for functions in an another
  38  * namespace (functions with an explicit prefix). This means that you cannot
  39  * use the <code>XPathFunctionResolver</code> to implement specifications
  40  * like <a href="http://www.w3.org/TR/xmldsig-core/">XML-Signature Syntax
  41  * and Processing</a> which extend the function library of XPath 1.0 in the
  42  * same namespace. This is a consequence of the design of the resolver.</p>
  43  *
  44  * <p>If you wish to implement additional built-in functions, you will have to
  45  * extend the underlying implementation directly.</p>
  46  *
  47  * @author  Norman Walsh
  48  * @author  Jeff Suttor
  49  * @see <a href="http://www.w3.org/TR/xpath#corelib">XML Path Language (XPath) Version 1.0, Core Function Library</a>
  50  * @since 1.5
  51  */
  52 public interface XPathFunctionResolver {
  53   /**
  54    * <p>Find a function in the set of available functions.</p>
  55    *
  56    * <p>If <code>functionName</code> or <code>arity</code> is <code>null</code>, then a <code>NullPointerException</code> is thrown.</p>
  57    *
  58    * @param functionName The function name.
  59    * @param arity The number of arguments that the returned function must accept.
  60    *
  61    * @return The function or <code>null</code> if no function named <code>functionName</code> with <code>arity</code> arguments exists.
  62    *
  63    * @throws NullPointerException If <code>functionName</code> or <code>arity</code> is <code>null</code>.
  64    */
  65   public XPathFunction resolveFunction(QName functionName, int arity);
  66 }
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