XPathExpression.evaluate(java.lang.Object item,QName returnType)should throw XPathExpressionException  when item is null and expression refers to the context

According to spec :
A null value for item indicates that the expression should be evaluated without a context . In the absence of a context item, simple expressions, such as "1+1", can be evaluated . Any expression that refers to the context will throw an XPathExpressionException

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java -version
java version "1.5.0-beta2"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0-beta2-b38)
Java HotSpot(TM) Client VM (build 1.5.0-beta2-b38, mixed mode)

javac Test12.java
java Test12
checkXPathExpression02() : failed - expected XPathExpressionException not thrown ::
checkXPathExpression14() : failed - expected XPathExpressionException not thrown ::

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Testcase - Test12.java
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import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathFactory;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactoryConfigurationException;
import javax.xml.xpath.XPathExpressionException;

import javax.xml.namespace.QName;

import org.w3c.dom.Document;

import org.xml.sax.InputSource;




public class Test12 {

   Document document1 = null;
   
   Test12 () {}
    
    // main()
    public static void main(String[] argv) {
        Test12 xpathExpression01 = new Test12();
        xpathExpression01.checkXPathExpression02();
        xpathExpression01.checkXPathExpression14();
    }// end main()
    
    
     // test for evaluate(java.lang.Object item,QName returnType)throws XPathExpressionException
    // item is null , A null value for item indicates that the expression should be evaluated without a context.
    // In the absence of a context item, simple expressions, such as "1+1", can be evaluated.
    // Any expression that refers to the context will throw an XPathExpressionException
    private void checkXPathExpression02() {
    	try{
    	  XPathFactory xpathFactory = XPathFactory.newInstance();
    	  if( xpathFactory instanceof XPathFactory ){
    	     XPath xpath = xpathFactory.newXPath();
	     if ( xpath instanceof XPath ){
		String expression = "/widgets/widget[@name='a']/@quantity" ;
		XPathExpression xpathExpression = xpath.compile(expression);
		String quantity = (String)xpathExpression.evaluate(document1, XPathConstants.STRING);
		System.out.println("checkXPathExpression02() : failed - expected XPathExpressionException not thrown :"+quantity+":");
	     }
    	     else{
    	        System.out.println("checkXPathExpression02() failed - xpath not instance of XPath");
    	     }    	  
    	  }else{
    	      System.out.println(" checkXPathExpression02() failed - creating instance of XPathFactory ");
    	  }  
    	}catch(NullPointerException npe ){
    	  System.out.println(" checkXPathExpression02() - failed ,  NPE thrown ");
    	}catch(XPathFactoryConfigurationException xpfce ){
    	  System.out.println(" checkXPathExpression02() - failed , Default object model not available ");
    	}catch(XPathExpressionException xpee ){
    	  System.out.println(" checkXPathExpression02() - passed , expected XPathExpressionException thrown ");
    	}catch(Exception e){
    	 System.out.println(" Exception thrown - checkXPathExpression02() failed ");
    	}
    }
   
    
    // test for evaluate(java.lang.Object item)throws XPathExpressionException    
    // when returnType is left off of the XPath.evaluate  method, all expressions are evaluated to a String value. 
    // item is null , A null value for item indicates that the expression should be evaluated without a context.
    // In the absence of a context item, simple expressions, such as "1+1", can be evaluated.
    // Any expression that refers to the context will throw an XPathExpressionException
    private void checkXPathExpression14() {
    	try{
    	  XPathFactory xpathFactory = XPathFactory.newInstance();
    	  if( xpathFactory instanceof XPathFactory ){
    	     XPath xpath = xpathFactory.newXPath();
	     if ( xpath instanceof XPath ){
		String expression = "/widgets/widget[@name='a']/@quantity" ;
		XPathExpression xpathExpression = xpath.compile(expression);
		String quantity = (String)xpathExpression.evaluate(document1 );
		System.out.println("checkXPathExpression14() : failed - expected XPathExpressionException not thrown :"+quantity+":");
	     }
    	     else{
    	        System.out.println("checkXPathExpression14() failed - xpath not instance of XPath");
    	     }    	  
    	  }else{
    	      System.out.println(" checkXPathExpression14() failed - creating instance of XPathFactory ");
    	  }  
    	}catch(NullPointerException npe ){
    	  System.out.println(" checkXPathExpression14() - failed ,  NPE thrown ");
    	}catch(XPathFactoryConfigurationException xpfce ){
    	  System.out.println(" checkXPathExpression14() - failed , Default object model not available ");
    	}catch(XPathExpressionException xpee ){
    	  System.out.println(" checkXPathExpression14() - passed , expected XPathExpressionException thrown ");
    	}catch(Exception e){
    	 System.out.println(" Exception thrown - checkXPathExpression14() failed ");
    	}
    }
    
}

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