date:20140425

Re: [JXPATH] Am I doing something stupid here?

2014-04-25 Thread John Casey



On 04/25/2014 12:42 PM, Matt Benson wrote:
Pointer is an interface that is considered part of the public API. 
Very possibly the intent could have been more elegantly expressed by 
using the NodePointer API, but this *would* be a case of relying on an 
implementation detail, as NodePointer is the Pointer implementation 
used by JXPathContextReferenceImpl.


Okay, so I need to read the docs more thoroughly. :)

Thanks for the help!



Matt


On Fri, Apr 25, 2014 at 12:39 PM, John Casey > wrote:


Yep, that makes a certain kind of sense, though I guess I wouldn't
exactly call it intuitive. I can see how creating a new context
each time could be a bad idea (and very inefficient, I
suspect)...though it seems (to a newbie anyway) that the pointers
are an implementation detail that leak out in this case.

Or, maybe I just haven't read enough of the docs?

At any rate, thanks for your reply. Maybe once this project I'm
working on is done, I'll take a look at modernizing JXPath. It
does seem faster than the built-in JAXP stuff.

-john



On 04/25/2014 12:33 PM, Matt Benson wrote:

Hi, John. Sorry for the long delay.

  The original authors of JXPath are long gone, but from what I
can reconstruct the intent of nested JXPathContexts is only to
unify treatment of things like variables, namespaces, and at a
guess, functions. AFAICT your test case appears to have
overcomplicated the issue, although notably my alternative does
resort to some string concatentation to accomplish the same
apparent purpose of the test case. Certainly the whole JXPath
codebase could benefit from some modernization. In any event, I have:

@Test
public void anotherTest() throws Exception {
final InputStream is =

Thread.currentThread().getContextClassLoader().getResourceAsStream("jxpath/simple.pom.xml");

final Document document =
DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(is);

final JXPathContext ctx = JXPathContext.newContext(document);

// not sure why this was done, but I have preserved it
document.getDocumentElement().removeAttribute("xmlns");

for (@SuppressWarnings("unchecked")
Iterator ptrs =
ctx.iteratePointers("/project/dependencies/dependency");
ptrs.hasNext();) {
final Pointer ptr = ptrs.next();
dump((Node) ptr.getNode());
System.out.printf("declared by project with groupId
'%s'%n", ctx.getValue(ptr.asPath() + "/ancestor::project/groupId"));
}
}

which yields output:


org.group
artifact-id
  2.6


declared by project with groupId 'org.test'

Does this help?

Matt


On Mon, Apr 14, 2014 at 1:09 PM, John Casey mailto:jdca...@apache.org>> wrote:

Hi all,

I'm trying to learn how to use JXPath with DOM in order to
speed up some code that uses a lot of xpath. I've seen blog
posts suggesting it's about twice as fast as JAXP's XPath
processor...

The problem I'm running into is when I construct a
JXPathContext around a node down in the DOM tree, then try to
select a node elsewhere in the tree using the ancestor::
axis. I'm attaching a sample XML file and unit test that
shows what I'm trying to do.

I've run this through a debugger, and it appears that the
DOMNodePointer.getImmediateParent() doesn't even try to look
at the Node.getParentNode()...if it doesn't have a
pre-existing parent (from its ctor) then it just dumbly
returns the null parent.

I haven't done enough research yet to know how to get
DOMNodePointer to populate its parent (using the public API,
not the nuts-and-bolts impl details), but in the attached
example you can see I try two approaches:

1. the naive approach, which is also the last one in the
code. IMO, this one should work!

2. a brute-force alternative, where JXPathContext instances
for each intermediate node are created to inherit in the
right order, all the way back to the document itself. From my
partial reading of the code, this should work even if the
naive approach doesn't.

Neither of these works, though. Can someone shed some light
on it, or let me know if I've found a bug (seems like a
common use case)...

Thanks,

-john

-- 
John Casey

GitHub - http://github.com/jdcasey


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Re: [JXPATH] Am I doing something stupid here?

2014-04-25 Thread John Casey

Yep, that makes a certain kind of sense, though I guess I wouldn't 
exactly call it intuitive. I can see how creating a new context each 
time could be a bad idea (and very inefficient, I suspect)...though it 
seems (to a newbie anyway) that the pointers are an implementation 
detail that leak out in this case.


Or, maybe I just haven't read enough of the docs?

At any rate, thanks for your reply. Maybe once this project I'm working 
on is done, I'll take a look at modernizing JXPath. It does seem faster 
than the built-in JAXP stuff.


-john


On 04/25/2014 12:33 PM, Matt Benson wrote:

Hi, John. Sorry for the long delay.

  The original authors of JXPath are long gone, but from what I can 
reconstruct the intent of nested JXPathContexts is only to unify 
treatment of things like variables, namespaces, and at a guess, 
functions. AFAICT your test case appears to have overcomplicated the 
issue, although notably my alternative does resort to some string 
concatentation to accomplish the same apparent purpose of the test 
case. Certainly the whole JXPath codebase could benefit from some 
modernization. In any event, I have:


@Test
public void anotherTest() throws Exception {
final InputStream is =
Thread.currentThread().getContextClassLoader().getResourceAsStream("jxpath/simple.pom.xml");

final Document document = 
DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(is);


final JXPathContext ctx = JXPathContext.newContext(document);

// not sure why this was done, but I have preserved it
document.getDocumentElement().removeAttribute("xmlns");

for (@SuppressWarnings("unchecked")
Iterator ptrs = 
ctx.iteratePointers("/project/dependencies/dependency"); 
ptrs.hasNext();) {

final Pointer ptr = ptrs.next();
dump((Node) ptr.getNode());
System.out.printf("declared by project with groupId 
'%s'%n", ctx.getValue(ptr.asPath() + "/ancestor::project/groupId"));

}
}

which yields output:


  org.group
  artifact-id
  2.6


declared by project with groupId 'org.test'

Does this help?

Matt


On Mon, Apr 14, 2014 at 1:09 PM, John Casey > wrote:


Hi all,

I'm trying to learn how to use JXPath with DOM in order to speed
up some code that uses a lot of xpath. I've seen blog posts
suggesting it's about twice as fast as JAXP's XPath processor...

The problem I'm running into is when I construct a JXPathContext
around a node down in the DOM tree, then try to select a node
elsewhere in the tree using the ancestor:: axis. I'm attaching a
sample XML file and unit test that shows what I'm trying to do.

I've run this through a debugger, and it appears that the
DOMNodePointer.getImmediateParent() doesn't even try to look at
the Node.getParentNode()...if it doesn't have a pre-existing
parent (from its ctor) then it just dumbly returns the null parent.

I haven't done enough research yet to know how to get
DOMNodePointer to populate its parent (using the public API, not
the nuts-and-bolts impl details), but in the attached example you
can see I try two approaches:

1. the naive approach, which is also the last one in the code.
IMO, this one should work!

2. a brute-force alternative, where JXPathContext instances for
each intermediate node are created to inherit in the right order,
all the way back to the document itself. From my partial reading
of the code, this should work even if the naive approach doesn't.

Neither of these works, though. Can someone shed some light on it,
or let me know if I've found a bug (seems like a common use case)...

Thanks,

-john

-- 
John Casey

GitHub - http://github.com/jdcasey


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To unsubscribe, e-mail: user-unsubscr...@commons.apache.org

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--
John Casey
---
GitHub:  https://github.com/jdcasey/
Twitter: http://twitter.com/buildchimp

Re: [JXPATH] Am I doing something stupid here?

2014-04-25 Thread Matt Benson

Pointer is an interface that is considered part of the public API. Very
possibly the intent could have been more elegantly expressed by using the
NodePointer API, but this *would* be a case of relying on an implementation
detail, as NodePointer is the Pointer implementation used by
JXPathContextReferenceImpl.

Matt


On Fri, Apr 25, 2014 at 12:39 PM, John Casey  wrote:

>  Yep, that makes a certain kind of sense, though I guess I wouldn't
> exactly call it intuitive. I can see how creating a new context each time
> could be a bad idea (and very inefficient, I suspect)...though it seems (to
> a newbie anyway) that the pointers are an implementation detail that leak
> out in this case.
>
> Or, maybe I just haven't read enough of the docs?
>
> At any rate, thanks for your reply. Maybe once this project I'm working on
> is done, I'll take a look at modernizing JXPath. It does seem faster than
> the built-in JAXP stuff.
>
> -john
>
>
>
> On 04/25/2014 12:33 PM, Matt Benson wrote:
>
> Hi, John. Sorry for the long delay.
>
>The original authors of JXPath are long gone, but from what I can
> reconstruct the intent of nested JXPathContexts is only to unify treatment
> of things like variables, namespaces, and at a guess, functions. AFAICT
> your test case appears to have overcomplicated the issue, although notably
> my alternative does resort to some string concatentation to accomplish the
> same apparent purpose of the test case. Certainly the whole JXPath codebase
> could benefit from some modernization. In any event, I have:
>
>  @Test
> public void anotherTest() throws Exception {
> final InputStream is =
>
> Thread.currentThread().getContextClassLoader().getResourceAsStream("jxpath/simple.pom.xml");
>
>  final Document document =
> DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(is);
>
>  final JXPathContext ctx = JXPathContext.newContext(document);
>
>  // not sure why this was done, but I have preserved it
> document.getDocumentElement().removeAttribute("xmlns");
>
>  for (@SuppressWarnings("unchecked")
> Iterator ptrs =
> ctx.iteratePointers("/project/dependencies/dependency"); ptrs.hasNext();) {
> final Pointer ptr = ptrs.next();
> dump((Node) ptr.getNode());
> System.out.printf("declared by project with groupId '%s'%n",
> ctx.getValue(ptr.asPath() + "/ancestor::project/groupId"));
> }
> }
>
>  which yields output:
>
>  
>   org.group
>   artifact-id
>   2.6
> 
>
>  declared by project with groupId 'org.test'
>
>  Does this help?
>
>  Matt
>
>
> On Mon, Apr 14, 2014 at 1:09 PM, John Casey  wrote:
>
>> Hi all,
>>
>> I'm trying to learn how to use JXPath with DOM in order to speed up some
>> code that uses a lot of xpath. I've seen blog posts suggesting it's about
>> twice as fast as JAXP's XPath processor...
>>
>> The problem I'm running into is when I construct a JXPathContext around a
>> node down in the DOM tree, then try to select a node elsewhere in the tree
>> using the ancestor:: axis. I'm attaching a sample XML file and unit test
>> that shows what I'm trying to do.
>>
>> I've run this through a debugger, and it appears that the
>> DOMNodePointer.getImmediateParent() doesn't even try to look at the
>> Node.getParentNode()...if it doesn't have a pre-existing parent (from its
>> ctor) then it just dumbly returns the null parent.
>>
>> I haven't done enough research yet to know how to get DOMNodePointer to
>> populate its parent (using the public API, not the nuts-and-bolts impl
>> details), but in the attached example you can see I try two approaches:
>>
>> 1. the naive approach, which is also the last one in the code. IMO, this
>> one should work!
>>
>> 2. a brute-force alternative, where JXPathContext instances for each
>> intermediate node are created to inherit in the right order, all the way
>> back to the document itself. From my partial reading of the code, this
>> should work even if the naive approach doesn't.
>>
>> Neither of these works, though. Can someone shed some light on it, or let
>> me know if I've found a bug (seems like a common use case)...
>>
>> Thanks,
>>
>> -john
>>
>> --
>> John Casey
>> GitHub - http://github.com/jdcasey
>>
>>
>> -
>> To unsubscribe, e-mail: user-unsubscr...@commons.apache.org
>> For additional commands, e-mail: user-h...@commons.apache.org
>>
>
>
> --
> John Casey
> ---
> GitHub:  https://github.com/jdcasey/
> Twitter: http://twitter.com/buildchimp
>
>

Re: [JXPATH] Am I doing something stupid here?

2014-04-25 Thread Matt Benson

Hi, John. Sorry for the long delay.

  The original authors of JXPath are long gone, but from what I can
reconstruct the intent of nested JXPathContexts is only to unify treatment
of things like variables, namespaces, and at a guess, functions. AFAICT
your test case appears to have overcomplicated the issue, although notably
my alternative does resort to some string concatentation to accomplish the
same apparent purpose of the test case. Certainly the whole JXPath codebase
could benefit from some modernization. In any event, I have:

@Test
public void anotherTest() throws Exception {
final InputStream is =

Thread.currentThread().getContextClassLoader().getResourceAsStream("jxpath/simple.pom.xml");

final Document document =
DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(is);

final JXPathContext ctx = JXPathContext.newContext(document);

// not sure why this was done, but I have preserved it
document.getDocumentElement().removeAttribute("xmlns");

for (@SuppressWarnings("unchecked")
Iterator ptrs =
ctx.iteratePointers("/project/dependencies/dependency"); ptrs.hasNext();) {
final Pointer ptr = ptrs.next();
dump((Node) ptr.getNode());
System.out.printf("declared by project with groupId '%s'%n",
ctx.getValue(ptr.asPath() + "/ancestor::project/groupId"));
}
}

which yields output:


  org.group
  artifact-id
  2.6


declared by project with groupId 'org.test'

Does this help?

Matt


On Mon, Apr 14, 2014 at 1:09 PM, John Casey  wrote:

> Hi all,
>
> I'm trying to learn how to use JXPath with DOM in order to speed up some
> code that uses a lot of xpath. I've seen blog posts suggesting it's about
> twice as fast as JAXP's XPath processor...
>
> The problem I'm running into is when I construct a JXPathContext around a
> node down in the DOM tree, then try to select a node elsewhere in the tree
> using the ancestor:: axis. I'm attaching a sample XML file and unit test
> that shows what I'm trying to do.
>
> I've run this through a debugger, and it appears that the 
> DOMNodePointer.getImmediateParent()
> doesn't even try to look at the Node.getParentNode()...if it doesn't have a
> pre-existing parent (from its ctor) then it just dumbly returns the null
> parent.
>
> I haven't done enough research yet to know how to get DOMNodePointer to
> populate its parent (using the public API, not the nuts-and-bolts impl
> details), but in the attached example you can see I try two approaches:
>
> 1. the naive approach, which is also the last one in the code. IMO, this
> one should work!
>
> 2. a brute-force alternative, where JXPathContext instances for each
> intermediate node are created to inherit in the right order, all the way
> back to the document itself. From my partial reading of the code, this
> should work even if the naive approach doesn't.
>
> Neither of these works, though. Can someone shed some light on it, or let
> me know if I've found a bug (seems like a common use case)...
>
> Thanks,
>
> -john
>
> --
> John Casey
> GitHub - http://github.com/jdcasey
>
>
> -
> To unsubscribe, e-mail: user-unsubscr...@commons.apache.org
> For additional commands, e-mail: user-h...@commons.apache.org
>

Re: [CSV] Wish: format-specific date generation

2014-04-25 Thread Benedikt Ritter

Agreed, feel free to raise an improvement ticket.


2014-04-22 14:24 GMT+02:00 Gary Gregory :

> For 1.0 at least, we do not plan on doing any type conversion. Later,
> perhaps, but the current thought is to leave type conversion to other
> components.
>
> Gary
>
>
> On Tue, Apr 22, 2014 at 7:22 AM, Rupert Wood  wrote:
>
> > Hi -
> >
> >
> >
> > It would be useful if printing a Java Date or Calendar to a
> CSVFormat.EXCEL
> > CSVPrinter would generate output that Excel recognises as a
> date-and-time.
> > For example the following
> >
> >
> >
> > PrintWriter outputWriter = new PrintWriter(new
> > FileOutputStream("output.csv"));
> >
> > CSVPrinter printer = new CSVPrinter(outputWriter, CSVFormat.EXCEL);
> >
> > printer.print(new Date());
> >
> > printer.println();
> >
> > printer.close();
> >
> >
> >
> > outputs the raw Date.toString()
> >
> >
> >
> > Tue Apr 22 12:06:42 BST 2014
> >
> >
> >
> > which Excel only treats as a string. (It will recognise e.g. /mm/dd
> as
> > a
> > date but I wouldn't know where to look for a definitive set of formats it
> > will consume.) Ditto probably printing Calendar.getInstance(), or the new
> > Java 8 LocalDate etc. classes.
> >
> >
> >
> > One argument against though is then the library perhaps ought to do the
> > reverse, i.e. spot that it has been passed a date in and construct a Date
> > class for the value at parse time which may be expensive and often
> > unnecessary.
> >
> >
> >
> > Thanks for your consideration. Happy to raise a JIRA 'Wish' ticket if
> this
> > seems reasonable.
> >
> >
> >
> > Rupert.
> >
> >
> >
> >
>
>
> --
> E-Mail: garydgreg...@gmail.com | ggreg...@apache.org
> Java Persistence with Hibernate, Second Edition<
> http://www.manning.com/bauer3/>
> JUnit in Action, Second Edition 
> Spring Batch in Action 
> Blog: http://garygregory.wordpress.com
> Home: http://garygregory.com/
> Tweet! http://twitter.com/GaryGregory
>



-- 
http://people.apache.org/~britter/
http://www.systemoutprintln.de/
http://twitter.com/BenediktRitter
http://github.com/britter

Re: [JXPATH] Am I doing something stupid here?

Re: [JXPATH] Am I doing something stupid here?

Re: [JXPATH] Am I doing something stupid here?

Re: [JXPATH] Am I doing something stupid here?

Re: [CSV] Wish: format-specific date generation

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