Name: eaR10174 Date: 10/30/2003


  The method

      public XPathFunction resolveFunction(QName functionName, int arity)

of the javax.xml.xpath.XPathFunctionResolver implementation is not invoked during
evaluation of xpath expression in case when an expression contains a user defined function
(see test.java below). According to the method XPath.evaluate() javadoc:
  
  public Object evaluate(String expression,
                       Object item,
                       QName returnType)
                throws XPathException
  ...
  If the expression contains a function reference, the function will be found through the
  function resolver. An exception is raised if the function resolver is undefined or the
  resolver returns null for the function.
                
the method should be invoked.

  The bug appears in jdk1.5.0beta-b25 and affects a new JCK1.5 test:

    api/javax_xml/xpath/XPath/index.html#Evaluate[Evaluate028]


------------------------------------test.java-----------------------------
import java.util.List;
import java.util.Iterator;
import javax.xml.namespace.QName;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathFactory;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathException;
import javax.xml.xpath.XPathFunction;
import javax.xml.xpath.XPathFunctionResolver;

public class test {

    public static void main (String[] args) {
        try {
            String expr = "join(1, 2, 3)";
            XPathFactory xpf = XPathFactory.newInstance(XPathConstants.DOM_OBJECT_MODEL);
            XPath xpath = xpf.newXPath();
            XPathFunctionResolver funcResolver = new XPathFunctionResolver() {
                public XPathFunction resolveFunction(QName functionName, int arity) {
                    System.out.println("resolveFunction: INVOKED.");
                    if (!"join".equals(functionName.getLocalPart()) || (arity != 3)) {
                        return null;
                    }
                    return new XPathFunction() {
                        public Object evaluate(List args) throws XPathException {
                            if (args.isEmpty()) {
                                return "";
                            }
                            StringBuffer sb = new StringBuffer();
                            for (Iterator i = args.iterator(); i.hasNext();) {
                                sb.append(i).append(",");
                            }
                            return sb.substring(0, sb.length() - 1);
                        }
                    };
                }
            };
            xpath.setFunctionResolver(funcResolver);

            String result = (String)xpath.evaluate(expr, (Object)null,
                                                   XPathConstants.STRING);

            if ("1,2,3".equals(result)) {
                System.out.println("OK");
            } else {
                System.out.println("Unexpected result is returned.");
            }
        } catch (XPathException e) {
            e.printStackTrace();
        }
    }
}
--------------------------------------------------------------------------
% java -showversion test
java version "1.5.0-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0-beta-b25)
Java HotSpot(TM) Client VM (build 1.5.0-beta-b25, mixed mode)

javax.xml.xpath.XPathException: javax.xml.transform.TransformerException: Could not find
function: join
        at com.sun.org.apache.xpath.internal.jaxp.XPathImpl.evaluate(XPathImpl.java:184)
        at test.main(test.java:40)
Caused by: javax.xml.transform.TransformerException: Could not find function: join
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.error(XPathParser.java:640)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.FunctionCall(XPathParser.java:1487)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.PrimaryExpr(XPathParser.java:1426)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.FilterExpr(XPathParser.java:1325)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.PathExpr(XPathParser.java:1258)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.UnionExpr(XPathParser.java:1216)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.UnaryExpr(XPathParser.java:1122)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.MultiplicativeExpr(XPathParser.java
:1043)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.AdditiveExpr(XPathParser.java:985)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.RelationalExpr(XPathParser.java:910
)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.EqualityExpr(XPathParser.java:850)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.AndExpr(XPathParser.java:814)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.OrExpr(XPathParser.java:787)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.Expr(XPathParser.java:770)
        at
com.sun.org.apache.xpath.internal.compiler.XPathParser.initXPath(XPathParser.java:163)
        at com.sun.org.apache.xpath.internal.XPath.<init>(XPath.java:200)
        at com.sun.org.apache.xpath.internal.XPath.<init>(XPath.java:236)
        at com.sun.org.apache.xpath.internal.jaxp.XPathImpl.eval(XPathImpl.java:124)
        at com.sun.org.apache.xpath.internal.jaxp.XPathImpl.evaluate(XPathImpl.java:181)
        ... 1 more
--------------------------------------------------------------------------

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