Hello,
Sorry that was the wrong code, I also tried it with :
System.out.println(objContext.getValue("getName(.[1], 1)"));
Here I got the stack trace of :
org.apache.commons.jxpath.JXPathException: Cannot invoke null;
java.lang.NullPointerException
at org.apache.commons.jxpath.functions.MethodFunction.invoke(
MethodFunction.java:94)
at org.apache.commons.jxpath.ri.compiler.ExtensionFunction.computeValue(
ExtensionFunction.java:92)
at org.apache.commons.jxpath.ri.JXPathContextReferenceImpl.getValue(
JXPathContextReferenceImpl.java:314)
at org.apache.commons.jxpath.ri.JXPathContextReferenceImpl.getValue(
JXPathContextReferenceImpl.java:280)
at
com.ziath.eventregistration.email.test.JXPathTestCase.testJXPathDirectCall(
JXPathTestCase.java:24)
It seems that .[1] is returning null?
Cheers,
Neil
On 3/5/07, Neil Benn <[EMAIL PROTECTED]> wrote:
Hello,
Thanks for the reply, I tested that as well with the following
code (sorry about the largish amount of code):
---
*
package
* com.ziath.eventregistration.email.test;
*
import
* java.util.ArrayList;
*import* java.util.List;
*
import
* org.apache.commons.jxpath.JXPathContext;
*
import
* junit.framework.TestCase;
*
public
* *class* JXPathTestCase *extends* * TestCase* {
*private *List<Person>
objTestList = *null* ;
*public* *void* setUp(){
objTestList = *new* ArrayList<Person>();
Person objPerson1 =
*new* Person("Neil", "Dave", "Benn");
Person objPerson2 =
*new* Person("John", "Bob", "Smith");
objTestList.add(objPerson1);
objTestList.add(objPerson2);
}
*public* *void* *testJXPathDirectCall*(){
JXPathContext objContext = JXPathContext.*newContext*(
objTestList);
System.
*out*.println(objContext.getValue(".[1]/getName(.[1], 1)"));
}
*public* *void* testJXPathRelativeMethodCall(){
JXPathContext objContext = JXPathContext.*newContext*(
objTestList);
System.
*out*.println(objContext.getRelativeContext(
objContext.getPointer(
".[1]"))
.getValue(
"getName(., 1)"));
}
*private* *static* *class * Person{
*private* List<String> lstNames = * null*;
/**
* [EMAIL PROTECTED] strFirstName
* [EMAIL PROTECTED] *strMiddleName*
* [EMAIL PROTECTED] *strLastName*
*/
*public* Person(String strFirstName, String strMiddleName, String
strLastName) {
*super*();
lstNames = *new* ArrayList<String>();
lstNames.add(strFirstName);
lstNames.add(strMiddleName);
*lstNames*.add(strLastName);
}
*public* *synchronized* *final * String getName(*int* piPosition){
*return* lstNames.get(piPosition);
}
*public* String toString(){
*return* lstNames.get(0) + " " +
lstNames.get(1) + " " +
lstNames.get(2) + " ";
}
}
}
--- However that givesme a traceback of :
org.apache.commons.jxpath.JXPathException: Cannot invoke null;
java.lang.NullPointerException
at org.apache.commons.jxpath.functions.MethodFunction.invoke(
MethodFunction.java:94)
at org.apache.commons.jxpath.ri.compiler.ExtensionFunction.computeValue (
ExtensionFunction.java:92)
at org.apache.commons.jxpath.ri.JXPathContextReferenceImpl.getValue(
JXPathContextReferenceImpl.java:314)
at org.apache.commons.jxpath.ri.JXPathContextReferenceImpl.getValue(
JXPathContextReferenceImpl.java :280)
at
com.ziath.eventregistration.email.test.JXPathTestCase.testJXPathDirectCall
(JXPathTestCase.java:24)
The thing is that I'm searching and searching for an example of how to do
this but not getting anywhere. Standard XPath (from W3C) notation (as far
as I can find) doesn't have this notion, the JXPath docs have an example
usaing a varibale but no example of how this variable is declared. The
other thing I've tried (as you can see above) is to get a pointer and use
this to make a relative context and call 'getPerson(., 1)' but that doesn't
work either.
Errm, I gonna try the nightly build to see if that has anything in it.
Any suggestions would be greatly appreciated!
Cheers,
Neil
On 3/5/07, Dmitri Plotnikov <[EMAIL PROTECTED]> wrote:
>
> Neil,
>
> In any case, please make sure that the syntax is right. You cannot use
> a
> method as a step in the path. It must be called as a function:
>
> "getQuestion(.[1], 'lastname')"
>
> Regards,
>
> - Dmitri
>
>
> ----- Original Message -----
> From: "Scott Heaberlin" <[EMAIL PROTECTED] >
> To: "Jakarta Commons Users List" <[email protected]>
> Sent: Sunday, March 04, 2007 9:05 PM
> Subject: Re: Calling a method with JXPath
>
>
> Odd. I know I've used instance methods in JXPath before. But I can't
> say I tried to do so where the instance method was on a member item of
> a collection.
>
> One thing I can say is that I've had difficulties in the past with the
> 1.2 release where my object graphs contain a mixture of maps,
> collections, and pojos.
>
> Suggestion - try your test case with one of the JXPath nightly builds.
> I had to do that because some fixes for traversing collections of
> collections which contain maps, etc. The 1.2 release is quite old.
>
> -Scott Heaberlin
>
> On 3/4/07, Neil Benn <[EMAIL PROTECTED]> wrote:
> > Hello,
> >
> > Thanks for the tip - I tried that but unfortunatly it does not
> work,
> > I
> > still get the same problem. The stack trace is now:
> >
> > ---
> >
> > org.apache.commons.jxpath.JXPathException : Invalid XPath:
> > '.[1]/getQuestion(.[1], \'lastname\')'. Syntax error after: '.[1]/g'
> >
> > org.apache.commons.jxpath.ri.Parser.parseExpression(Parser.java:60)
> >
> org.apache.commons.jxpath.ri.JXPathContextReferenceImpl.compileExpression(
> JXPathContextReferenceImpl.java:218)
> > org.apache.commons.jxpath.ri.JXPathContextReferenceImpl.getValue(
> JXPathContextReferenceImpl.java:247)
> >
> > ---
> >
> > It is the same problem. Interestingly I did try putting a list into
> the
> > JXContext and calling size as follows:
> >
> > List objValues = new ArrayList<String>();
> > objValues.add("test1");
> > objValues.add("test2");
> > JXPathContext objContext = JXPathContext.newContext(objValues);
> > System.out.println(objContext.getValue("size(.)"));
> > assertEquals("test1", objContext.getValue(".[1]"));
> >
> > This works, it prints out 2 for the size of the list. I wonder if
> it is
> > because the method I am calling has parameters? In the meantime, I'm
> > gonna
> > trawl trhough the testcases in the source to see if I can find an
> example.
> >
> > Thanks for your assistance.
> >
> > Cheers,
> >
> > Neil
> >
> > "Scott Heaberlin" <[EMAIL PROTECTED]> wrote:
> >
> > > Try passing the object on which you want to call the method as the
> > > first arg in the xpath function (the object's method).
> > >
> > > .[1]/getQuestion(.[1], 'lastname')
> > >
> > > Object methods take the syntax above as part of JXPath's standard
> > > extension functions.
> > >
> > >
> >
http://jakarta.apache.org/commons/jxpath/users-guide.html#Standard_Extension_Functions
>
> > >
> > > Hope this helps,
> > >
> > > -Scott Heaberlin
> > >
> > > On 3/3/07, Neil Benn <[EMAIL PROTECTED]> wrote:
> > > > Hello,
> > > >
> > > >
> > > >
> > > > I have a a strane problem when I'm trying to call a
> method
> > with
> > > > JXPath. The object graph has a user which has a method called
> > > > getQuestion(String pstrQuestionID). The JXPath I have written for
> > > > this
> > is:
> > > >
> > > >
> > > >
> > > > .[1]/getQuestion(\'lastname\')
> > > >
> > > >
> > > > The dot at the front is notation to allow me to access
> the
> > first
> > > > element, the root of the context is a list. However when I
> attempt to
> > > > run
> > > > this I get the following stack trace :
> > > >
> > > >
> > > >
> > > > org.apache.commons.jxpath.JXPathException: Invalid XPath:
> > > > '.[1]/getQuestion(\'lastname\')'. Syntax error after: '.[1]/g'
> > > > org.apache.commons.jxpath.ri.Parser.parseExpression(Parser.java
> :60)
> > > >
> > >
> >
> org.apache.commons.jxpath.ri.JXPathContextReferenceImpl.compileExpression
> (JXPathContextReferenceImpl.java :218)
> > > >
> > >
> > org.apache.commons.jxpath.ri.JXPathContextReferenceImpl.getValue(
> JXPathContextReferenceImpl.java:247)
> > > >
> > > >
> > > > However as far as I can see, the XPath notation is
> valid –
> > > > I
> > > would
> > > > be most grateful is someone could let me know what I've done
> wrong.
> > > >
> > > >
> > > >
> > > > Thanks, in advance for your help.
> > > >
> > > >
> > > >
> > > > Cheers,
> > > >
> > > >
> > > >
> > > > Neil
> > > >
> > > >
> > > >
> > > > ---
> > > >
> > > > Neil Benn Msc
> > > >
> > > > CEO Ziath Ltd
> > > >
> > > > Website - http://www.ziath.com
> > > >
> > > > Blog - http://labauto-lounge.com
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> ---------------------------------------------------------------------
> > > > To unsubscribe, e-mail:
> [EMAIL PROTECTED]
> > > > For additional commands, e-mail:
> [EMAIL PROTECTED]
> > > >
> > > >
> > >
> > >
> ---------------------------------------------------------------------
> > > To unsubscribe, e-mail: [EMAIL PROTECTED]
> > > For additional commands, e-mail:
> [EMAIL PROTECTED]
> > >
> > >
> > ---
> >
> > Neil Benn Msc
> > CEO Ziath Ltd
> > Website - http://www.ziath.com
> > Blog - http://labauto-lounge.com
> >
> >
> >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: [EMAIL PROTECTED]
> > For additional commands, e-mail: [EMAIL PROTECTED]
> >
> >
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [EMAIL PROTECTED]
> For additional commands, e-mail: [EMAIL PROTECTED]
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [EMAIL PROTECTED]
> For additional commands, e-mail: [EMAIL PROTECTED]
>
>
