Re: JXPath over Generic Collection?, How?
A whirl and a win!
I'm very close to a complete solution here (with loads of assistance from
Matt, THANK YOU) based on Dyna Beans however there is one remaining problem
(since we have duplicate elements).
According to: http://www.w3.org/TR/xpath#path-abbrev
http://www.w3.org/TR/xpath#path-abbrev
* selects all element children of the context node
Expression: '/root/animal/dog/*' should return all dog's, instead it returns
the first() dog (BOXER) only. I am unsure if this in an unrealistic
requirement of JXPath and also where should I look to possibly 'fix' this if
it indeed would compliment the current features?
Thanks HEAPS!
On Thu, Mar 5, 2009 at 3:05 AM, Matt Benson gudnabr...@yahoo.com wrote:
Apparently the reason I was so ready to agree this was a bug that should be
fixed is that I already fixed it as
http://issues.apache.org/jira/browse/JXPATH-128 . So since you're already
experienced with building JXPath now you should be able to build from svn
trunk and give that a whirl.
-Matt
--- On Wed, 3/4/09, Matt Benson gudnabr...@yahoo.com wrote:
From: Matt Benson gudnabr...@yahoo.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Wednesday, March 4, 2009, 7:57 AM
Hi Andrew,
I agree that going through the list of properties
should avoid the explicit class check problem (I think
this is because you are using LazyDynaBeans instead of
regular DynaBeans). As for returning all matches vs.
the first match, rather than selectValue(...) you need to
selectNodes(...), or iterate(...). There are other
useful methods, e.g. those dealing with pointers, also
available on JXPathContext.
So as for your bug, yes it can/should be fixed, but you
might also consider whether you can use non-lazy DynaBeans
instead.
Regards,
Matt
--- On Tue, 3/3/09, Andrew Hughes ahhug...@gmail.com
wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?,
How?
To: Commons Users List user@commons.apache.org
Date: Tuesday, March 3, 2009, 5:37 PM
For efficiency reasons I can see why
you are using String[] here and not
List.add()...
Anyway, I have a fix (sort of) for this bug. The
number of
names needs to be
calculated a little differently to what it currently
is...
public String[] getPropertyNames() {
/* @todo do something about the
sorting - LIKE WHAT? - MJB */
if (names == null) {
DynaClass
dynaClass = dynaBean.getDynaClass();
DynaProperty[]
properties = dynaClass.getDynaProperties();
int count =
properties.length;
boolean hasClass
= dynaClass.getDynaProperty(class) != null;
//count the
number of property names we have
count = 0;
for (int i = 0; i
properties.length; i++) {
String name = properties[i].getName();
if
(!hasClass || !name.equals(class)) {
count++; //it's only a property is it's not a
class and
doesn't just have a class property.
}
}
//read the
property names into a String[] to return
names = new
String[count];
for (int i = 0, j
= 0; i properties.length; i++) {
String name = properties[i].getName();
if
(!hasClass || !name.equals(class)) {
names[j++] = name;
}
}
Arrays.sort(names);
}
return names;
}
Now I can sort of sucessfully run all my expressions,
yippee!! However, I
now have a problem with multiple deep results. Queries
like
//dog/* I would
expect to return all dog's[] but this just returns
the
first one it finds.
Maybe this is asking a little too much of JXPath and
child/node
step-up/step-down traversal? Matt can probably tell me
if
this is or is not
the case plase :)
On Wed, Mar 4, 2009 at 9:38 AM, Andrew Hughes ahhug...@gmail.com
wrote:
Pretty sure this is a bug in JXPath - and it is
not
tested by the current
unit tests.
I can't quite work out 100% of what's going on
here...
but it has to do
with gathering the property names from a
DynaBean
child member of a (parent)
DynaBean. Especially, when it try's to deal with
the
property named 'name'
and 'class'.
The problem with query '//dog' etc's
'ArrayOutOfBoundsException 0' occurs
below. And rightfully so, names[] is a zero
length
array and for some
reason JXPath is trying to set a value for the
first
entry of a zero length
array. That aint ever going to work! But why
is
the array length zero?
Because the properties.length==1, however the
'hasClass==true' and it's
count-- then negates the correct count calculated
from
Re: JXPath over Generic Collection?, How?
For me:
context.selectNodes(/root/animal/dog/*[name])
selects
[LazyDynaBean {name=(BOXER)}, LazyDynaBean {name=(LABRADOR)}]
--- On Wed, 3/11/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Wednesday, March 11, 2009, 1:12 AM
A whirl and a win!
I'm very close to a complete solution here (with loads of
assistance from
Matt, THANK YOU) based on Dyna Beans however there is one
remaining problem
(since we have duplicate elements).
According to: http://www.w3.org/TR/xpath#path-abbrev
http://www.w3.org/TR/xpath#path-abbrev
* selects all element children of the context node
Expression: '/root/animal/dog/*' should return all dog's,
instead it returns
the first() dog (BOXER) only. I am unsure if this in an
unrealistic
requirement of JXPath and also where should I look to
possibly 'fix' this if
it indeed would compliment the current features?
Thanks HEAPS!
On Thu, Mar 5, 2009 at 3:05 AM, Matt Benson gudnabr...@yahoo.com
wrote:
Apparently the reason I was so ready to agree this was
a bug that should be
fixed is that I already fixed it as
http://issues.apache.org/jira/browse/JXPATH-128 .
So since you're already
experienced with building JXPath now you should be
able to build from svn
trunk and give that a whirl.
-Matt
--- On Wed, 3/4/09, Matt Benson gudnabr...@yahoo.com
wrote:
From: Matt Benson gudnabr...@yahoo.com
Subject: Re: JXPath over Generic
Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Wednesday, March 4, 2009, 7:57 AM
Hi Andrew,
I agree that going through the
list of properties
should avoid the explicit class check problem
(I think
this is because you are using LazyDynaBeans
instead of
regular DynaBeans). As for returning all
matches vs.
the first match, rather than selectValue(...) you
need to
selectNodes(...), or iterate(...). There
are other
useful methods, e.g. those dealing with pointers,
also
available on JXPathContext.
So as for your bug, yes it can/should be fixed,
but you
might also consider whether you can use non-lazy
DynaBeans
instead.
Regards,
Matt
--- On Tue, 3/3/09, Andrew Hughes ahhug...@gmail.com
wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic
Collection?,
How?
To: Commons Users List user@commons.apache.org
Date: Tuesday, March 3, 2009, 5:37 PM
For efficiency reasons I can see why
you are using String[] here and not
List.add()...
Anyway, I have a fix (sort of) for this bug.
The
number of
names needs to be
calculated a little differently to what it
currently
is...
public String[]
getPropertyNames() {
/*
@todo do something about the
sorting - LIKE WHAT? - MJB */
if
(names == null) {
DynaClass
dynaClass = dynaBean.getDynaClass();
DynaProperty[]
properties = dynaClass.getDynaProperties();
int count =
properties.length;
boolean hasClass
= dynaClass.getDynaProperty(class) !=
null;
//count the
number of property names we have
count = 0;
for (int i = 0; i
properties.length; i++) {
String name = properties[i].getName();
if
(!hasClass || !name.equals(class)) {
count++; //it's only
a property is it's not a
class and
doesn't just have a class property.
}
}
//read the
property names into a String[] to return
names = new
String[count];
for (int i = 0, j
= 0; i properties.length; i++) {
String name = properties[i].getName();
if
(!hasClass || !name.equals(class)) {
names[j++] = name;
}
}
Arrays.sort(names);
}
return
names;
}
Now I can sort of sucessfully run all my
expressions,
yippee!! However, I
now have a problem with multiple deep
results. Queries
like
//dog/* I would
expect to return all dog's[] but this just
returns
the
first one it finds.
Maybe this is asking a little too much of
JXPath and
child/node
step-up/step-down traversal? Matt can
probably tell me
if
this is or is not
the case plase :)
On Wed, Mar 4, 2009 at 9:38 AM, Andrew
Hughes ahhug...@gmail.com
wrote:
Pretty sure this is a bug in JXPath -
and it is
not
tested by the current
unit tests.
I can't quite work out 100% of what's
going on
here...
but it has to do
with gathering the property names from
a
DynaBean
child member of a (parent
Re: JXPath over Generic Collection?, How?
Hi Andrew,
I agree that going through the list of properties should avoid the explicit
class check problem (I think this is because you are using LazyDynaBeans
instead of regular DynaBeans). As for returning all matches vs. the first
match, rather than selectValue(...) you need to selectNodes(...), or
iterate(...). There are other useful methods, e.g. those dealing with
pointers, also available on JXPathContext.
So as for your bug, yes it can/should be fixed, but you might also consider
whether you can use non-lazy DynaBeans instead.
Regards,
Matt
--- On Tue, 3/3/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Tuesday, March 3, 2009, 5:37 PM
For efficiency reasons I can see why
you are using String[] here and not
List.add()...
Anyway, I have a fix (sort of) for this bug. The number of
names needs to be
calculated a little differently to what it currently is...
public String[] getPropertyNames() {
/* @todo do something about the
sorting - LIKE WHAT? - MJB */
if (names == null) {
DynaClass
dynaClass = dynaBean.getDynaClass();
DynaProperty[]
properties = dynaClass.getDynaProperties();
int count =
properties.length;
boolean hasClass
= dynaClass.getDynaProperty(class) != null;
//count the
number of property names we have
count = 0;
for (int i = 0; i
properties.length; i++) {
String name = properties[i].getName();
if
(!hasClass || !name.equals(class)) {
count++; //it's only a property is it's not a
class and
doesn't just have a class property.
}
}
//read the
property names into a String[] to return
names = new
String[count];
for (int i = 0, j
= 0; i properties.length; i++) {
String name = properties[i].getName();
if
(!hasClass || !name.equals(class)) {
names[j++] = name;
}
}
Arrays.sort(names);
}
return names;
}
Now I can sort of sucessfully run all my expressions,
yippee!! However, I
now have a problem with multiple deep results. Queries like
//dog/* I would
expect to return all dog's[] but this just returns the
first one it finds.
Maybe this is asking a little too much of JXPath and
child/node
step-up/step-down traversal? Matt can probably tell me if
this is or is not
the case plase :)
On Wed, Mar 4, 2009 at 9:38 AM, Andrew Hughes ahhug...@gmail.com
wrote:
Pretty sure this is a bug in JXPath - and it is not
tested by the current
unit tests.
I can't quite work out 100% of what's going on here...
but it has to do
with gathering the property names from a DynaBean
child member of a (parent)
DynaBean. Especially, when it try's to deal with the
property named 'name'
and 'class'.
The problem with query '//dog' etc's
'ArrayOutOfBoundsException 0' occurs
below. And rightfully so, names[] is a zero length
array and for some
reason JXPath is trying to set a value for the first
entry of a zero length
array. That aint ever going to work! But why is
the array length zero?
Because the properties.length==1, however the
'hasClass==true' and it's
count-- then negates the correct count calculated from
properties.length. I
think the problem is in the hasClass calculation...
'boolean hasClass =
dynaClass.getDynaProperty(class) != null;' or
the conditional 'if'
statement. I don't understand the JXPath logic here
completely, but I know
it doesn't deal with the way I am using it and I
genuinely feel this is a
bug we can fix :'(
public String[]
getPropertyNames() {
/* @todo do
something about the sorting - LIKE WHAT? - MJB */
if (names ==
null) {
DynaClass dynaClass =
dynaBean.getDynaClass();
DynaProperty[] properties =
dynaClass.getDynaProperties();
//returns one property 'name=root' (correct)
int count = properties.length;
//returns/set's '1' (correct)
boolean hasClass =
dynaClass.getDynaProperty(class) != null;
//returns/sets 'true' (?unknown?)
if
(hasClass) { //this is true and executes
count--; //
Exclude class from properties
}
names = new String[count]; //names is a
zero length array.
WRONG!!! I do have at least 1 property called
'name'
for (int i = 0, j = 0; i
properties.length; i++) {
String name = properties[i].getName();
if (!hasClass || !name.equals(class)) {
names[j++] = name; //it breaks
here
ArrayOutOfBoundsException 0! WRONG
Re: JXPath over Generic Collection?, How?
Apparently the reason I was so ready to agree this was a bug that should be
fixed is that I already fixed it as
http://issues.apache.org/jira/browse/JXPATH-128 . So since you're already
experienced with building JXPath now you should be able to build from svn trunk
and give that a whirl.
-Matt
--- On Wed, 3/4/09, Matt Benson gudnabr...@yahoo.com wrote:
From: Matt Benson gudnabr...@yahoo.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Wednesday, March 4, 2009, 7:57 AM
Hi Andrew,
I agree that going through the list of properties
should avoid the explicit class check problem (I think
this is because you are using LazyDynaBeans instead of
regular DynaBeans). As for returning all matches vs.
the first match, rather than selectValue(...) you need to
selectNodes(...), or iterate(...). There are other
useful methods, e.g. those dealing with pointers, also
available on JXPathContext.
So as for your bug, yes it can/should be fixed, but you
might also consider whether you can use non-lazy DynaBeans
instead.
Regards,
Matt
--- On Tue, 3/3/09, Andrew Hughes ahhug...@gmail.com
wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?,
How?
To: Commons Users List user@commons.apache.org
Date: Tuesday, March 3, 2009, 5:37 PM
For efficiency reasons I can see why
you are using String[] here and not
List.add()...
Anyway, I have a fix (sort of) for this bug. The
number of
names needs to be
calculated a little differently to what it currently
is...
public String[] getPropertyNames() {
/* @todo do something about the
sorting - LIKE WHAT? - MJB */
if (names == null) {
DynaClass
dynaClass = dynaBean.getDynaClass();
DynaProperty[]
properties = dynaClass.getDynaProperties();
int count =
properties.length;
boolean hasClass
= dynaClass.getDynaProperty(class) != null;
//count the
number of property names we have
count = 0;
for (int i = 0; i
properties.length; i++) {
String name = properties[i].getName();
if
(!hasClass || !name.equals(class)) {
count++; //it's only a property is it's not a
class and
doesn't just have a class property.
}
}
//read the
property names into a String[] to return
names = new
String[count];
for (int i = 0, j
= 0; i properties.length; i++) {
String name = properties[i].getName();
if
(!hasClass || !name.equals(class)) {
names[j++] = name;
}
}
Arrays.sort(names);
}
return names;
}
Now I can sort of sucessfully run all my expressions,
yippee!! However, I
now have a problem with multiple deep results. Queries
like
//dog/* I would
expect to return all dog's[] but this just returns
the
first one it finds.
Maybe this is asking a little too much of JXPath and
child/node
step-up/step-down traversal? Matt can probably tell me
if
this is or is not
the case plase :)
On Wed, Mar 4, 2009 at 9:38 AM, Andrew Hughes ahhug...@gmail.com
wrote:
Pretty sure this is a bug in JXPath - and it is
not
tested by the current
unit tests.
I can't quite work out 100% of what's going on
here...
but it has to do
with gathering the property names from a
DynaBean
child member of a (parent)
DynaBean. Especially, when it try's to deal with
the
property named 'name'
and 'class'.
The problem with query '//dog' etc's
'ArrayOutOfBoundsException 0' occurs
below. And rightfully so, names[] is a zero
length
array and for some
reason JXPath is trying to set a value for the
first
entry of a zero length
array. That aint ever going to work! But why
is
the array length zero?
Because the properties.length==1, however the
'hasClass==true' and it's
count-- then negates the correct count calculated
from
properties.length. I
think the problem is in the hasClass
calculation...
'boolean hasClass =
dynaClass.getDynaProperty(class) != null;'
or
the conditional 'if'
statement. I don't understand the JXPath logic
here
completely, but I know
it doesn't deal with the way I am using it and I
genuinely feel this is a
bug we can fix :'(
public String[]
getPropertyNames() {
/* @todo do
something about the sorting - LIKE WHAT? - MJB */
if (names ==
null) {
DynaClass dynaClass =
dynaBean.getDynaClass();
DynaProperty[] properties =
dynaClass.getDynaProperties();
//returns one property 'name=root' (correct)
int count = properties.length;
//returns/set's
Re: JXPath over Generic Collection?, How?
); //absolute
single
runEvaluation(/root/animal/cat/tiger, context); //absolute
multiple
//everything below fails
runEvaluation(/root/animal/cat/tiger[last()], context);
//absolute single
runEvaluation(/root/animal/dog/*, context); //absolute
multiple
runEvaluation(//dog, context); //deep search
runEvaluation(//dog/*, context);//deep multiple
runEvaluation(//cat/*[objectName='LION'], context);//deep filter
}
public static void runEvaluation(String expression,JXPathContext
context){
log.info(About to evaulate the expression: +expression);
try {
Object value = context.getValue(expression);
//we got a single result.
if (value instanceof LazyDynaBean) {
LazyDynaBean r = (LazyDynaBean)context.getValue(expression);
log.info(Ran ' + expression + ' and got objectName=' +
r.get(objectName) + ');
}
//we got multiple results
else if (value instanceof ArrayList) {
String titles = ;
for (LazyDynaBean bean : ((ArrayListLazyDynaBean) value )){
titles += (bean.get(objectName)+,);
}
log.info(Ran + expression + and got +((ArrayList)value).size()+
results: +titles);
}
//we got a non-dyna bean.
else {
log.info(Ran ' + expression + ' and got a class ' +
value.getClass().getName() + ' with toString() ' +value.toString() + ');
}
} catch (Exception e) {
// TODO Auto-generated catch block
log.error(Failed to evaluate +expression,e);
}
}
}
On Fri, Feb 27, 2009 at 3:56 AM, Matt Benson gudnabr...@yahoo.comwrote:
Those paths work for me. Maybe something else is going awry?
-Matt
--- On Thu, 2/26/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Thursday, February 26, 2009, 12:53 AM
Many queries don't work, I
can't get any results for the following (code
taken from previous email)...
runEvaluation(/root/animal/cat/tiger[last()], context);
//absolute
single
runEvaluation(/root/animal/dog/*, context); //absolute
multiple
runEvaluation(//dog,
context); //deep search
runEvaluation(//dog/*,
context);//deep multiple
runEvaluation(//cat/*[objectName='LION'], context);//deep
filter
These are the really interesting benefits on xpath that I
would dearly like
to have.
A Huge Thanks once again for your reply Matt!!! :)
On Thu, Feb 26, 2009 at 10:55 AM, Matt Benson gudnabr...@yahoo.com
wrote:
How so? If you simply treat the name property as
an element rather than an
attribute, you're done, no?
-Matt
--- On Wed, 2/25/09, Andrew Hughes ahhug...@gmail.com
wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic
Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Wednesday, February 25, 2009, 6:22 PM
Indeed Matt, you are correct and I do
apologize... but I must say I find
your emailed explanation much better. Kudos
Thanks!
I'll (finally) get a chance to work on this
tomorrow, but I
think I am still
stuck :'(
Cheers for everything so far
On Tue, Feb 24, 2009 at 1:43 PM, Matt Benson
gudnabr...@yahoo.com
wrote:
I won't get to look at this again at least
before
tomorrow (9PM for me now
and still have some late-night $work to look
at), but
I thought I would
mention straight off that the @name feature
actually
IS mentioned in the
userguide under the section about working
with
(java.util.)Maps. If you
have a suggestion of where in the guide
would be
another good place to
mention it as a caveat and/or even the
wording to use,
feel free to open a
documentation issue in JIRA for it.
TBC,
Matt
--- On Mon, 2/23/09, Andrew Hughes ahhug...@gmail.com
wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic
Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Monday, February 23, 2009, 6:24
PM
Hi Matt,
Thanks HEAPS for you reply, I am really
really
really
grateful. I think that
I have progressed just a little with
this but
there are
still some BIG
shortfalls with this. I've attached
code that
should run
out the box and is
based on previous emails. If I can get
the
expressions
below to correctly
evaluate I would be heaps happy.
Thanks heaps again, hopefully this will
work soon
enough.
p.s. I can understand the 'name' vs
'@name',
perhaps the
userguide could
mention this is about all I can add.
code...
package rnd;
import java.util.ArrayList;
import
org.apache.commons.beanutils.LazyDynaBean
Re: JXPath over Generic Collection?, How?
OK, email #19 to the list. I'm both incredibly patient and skeptical that
this will ever work. I might try and run this in a debugger and track down
how JXPath traverses the DynaBean but given the reflection involved
that might be a painful task.
--AH
On Tue, Feb 17, 2009 at 1:11 PM, Andrew Hughes ahhug...@gmail.com wrote:
Ping... if anyone can help with this JXPath DynaBeans problem I'd be
REALLY THANKFUL :)
On Fri, Feb 13, 2009 at 1:55 PM, Andrew Hughes ahhug...@gmail.com wrote:
Howdy,
I've taken Matt's suggestion onboard and I have investigated DynaBeans.
These look pretty good for all intestive purposes and there's a code
examples below how to build the data structure:
+ root [...@name=ROOT]
+ animal [...@name=ANIMAL]
+ dog [...@name=DOG]
+ boxer [...@name=BOXER]
+ labrador [...@name=LABRADOR]
+ cat [...@name=CAT]
+ tiger [...@name=TIGER-ONE]
+ tiger [...@name=TIGER-TWO]
+ tiger [...@name=TIGER-THREE]
+ lion [...@name=LION]
And the code looks like...
LazyDynaBean lazyDynaBean = new LazyDynaBean(); //the transparent root.
LazyDynaBean root = new LazyDynaBean();
LazyDynaBean animal = new LazyDynaBean();
LazyDynaBean dog = new LazyDynaBean();
LazyDynaBean cat = new LazyDynaBean();
LazyDynaBean boxer = new LazyDynaBean();
LazyDynaBean labrador = new LazyDynaBean();
LazyDynaBean tiger1 = new LazyDynaBean();
LazyDynaBean tiger2 = new LazyDynaBean();
LazyDynaBean tiger3 = new LazyDynaBean();
LazyDynaBean lion = new LazyDynaBean();
//set the @name property of each bean, user UPPER to make them distinct
for examples.
root.set(name,ROOT);
animal.set(name,ANIMAL);
dog.set(name,DOG);
cat.set(name,CAT);
boxer.set(name,BOXER);
labrador.set(name,LABRADOR);
tiger1.set(name,TIGER-ONE);
tiger2.set(name,TIGER-TWO);
tiger3.set(name,TIGER-THREE);
lion.set(name,LION);
//build the bean hierarchy.
lazyDynaBean.set(root,0, root);
root.set(animal,0, animal);
animal.set(dog,0,dog);
animal.set(cat,0,cat);
dog.set(labrador,0,labrador);
dog.set(boxer,0, boxer);
cat.set(tiger,0,tiger1);//duplicate
cat.set(tiger,1,tiger2);//duplicate
cat.set(tiger,1,tiger3);//duplicate
cat.set(lion,0,lion);
JXPathContext context = JXPathContext.newContext(lazyDynaBean);
String query = /root/animal/cat/tiger;
Object value = context.getValue(query);
But there's a problem with JXPath querying this also. Absolute Paths like
'/root/animal/cat/tiger' or '/root/animal/cat/tiger'[2]' work perfectly.
But I don't have anyluck doing deep searches. For examples the following
just won't work.
'//cat'
//*...@name='LION']
/root/animal/cat/tig...@name='TIGER-TWO']
Things are looking up, but is this behavior to be expected?
Cheers,
--AH
On Thu, Feb 12, 2009 at 6:43 AM, Matt Benson gudnabr...@yahoo.comwrote:
--- On Wed, 2/11/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Wednesday, February 11, 2009, 4:19 AM
Still No Luck, I have removed recursive generic collections
and have tried
the following code... this is becoming a marathon effort
:'(
public class Thing {
public Thing(String name) {
this.name = name;
}
private String name = ;
public String getName() {
return name;
}
private ArrayListThing children = new
ArrayListThing();
public ArrayListThing getChildren() {
return children;
}
}
public static void main(String[] args) {
//get some same data
Thing animal = new Thing(Animal);
//Animal.Dog.*
Thing dog = new Thing(Dog);
dog.getChildren().add(new
Thing(Labrador));
dog.getChildren().add(new
Thing(Boxer));
animal.getChildren().add(dog);
//Animal.Cat.*
Thing cat = new Thing(Cat);
cat.getChildren().add(new Thing(Lion));
cat.getChildren().add(new
Thing(Tiger));
animal.getChildren().add(cat);
//run a query on it
JXPathContext context =
JXPathContext.newContext(animal);
String query = /Animal;
Thing result = (Thing) context.getValue(query);
String path = context.getPointer(query).asPath();
System.out.println(Ran ' + query +
' and got ' +
result.getName() + ' on path ' + path +
'.);
}
What would you be trying to select? If you want to know how to look for
a given Thing in this graph, I can probably help. If you want to know what
graph will allow you to use a preconceived notion of the xpath you want to
use, that will be harder. You might use [beanutils] dynabeans in
conjunction with [jxpath] to try and achieve the latter.
-Matt
On Wed, Feb 11, 2009 at 3:08 PM, Andrew Hughes
Re: JXPath over Generic Collection?, How?
Andrew,
I've been meaning to look into this but haven't yet. If you have any
ready-to-run code you can send to the list, that wouldn't hurt...
-Matt
--- On Mon, 2/23/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Monday, February 23, 2009, 5:42 AM
OK, email #19 to the list. I'm both
incredibly patient and skeptical that
this will ever work. I might try and run this in a debugger
and track down
how JXPath traverses the DynaBean but given the
reflection involved
that might be a painful task.
--AH
On Tue, Feb 17, 2009 at 1:11 PM, Andrew Hughes ahhug...@gmail.com
wrote:
Ping... if anyone can help with this JXPath
DynaBeans problem I'd be
REALLY THANKFUL :)
On Fri, Feb 13, 2009 at 1:55 PM, Andrew Hughes ahhug...@gmail.com
wrote:
Howdy,
I've taken Matt's suggestion onboard and I have
investigated DynaBeans.
These look pretty good for all intestive purposes
and there's a code
examples below how to build the data structure:
+ root [...@name=ROOT]
+ animal [...@name=ANIMAL]
+ dog
[...@name=DOG]
+ boxer [...@name=BOXER]
+ labrador [...@name=LABRADOR]
+ cat
[...@name=CAT]
+ tiger [...@name=TIGER-ONE]
+ tiger [...@name=TIGER-TWO]
+ tiger [...@name=TIGER-THREE]
+ lion [...@name=LION]
And the code looks like...
LazyDynaBean lazyDynaBean = new
LazyDynaBean(); //the transparent root.
LazyDynaBean root = new LazyDynaBean();
LazyDynaBean animal = new LazyDynaBean();
LazyDynaBean dog = new LazyDynaBean();
LazyDynaBean cat = new LazyDynaBean();
LazyDynaBean boxer = new LazyDynaBean();
LazyDynaBean labrador = new LazyDynaBean();
LazyDynaBean tiger1 = new LazyDynaBean();
LazyDynaBean tiger2 = new LazyDynaBean();
LazyDynaBean tiger3 = new LazyDynaBean();
LazyDynaBean lion = new LazyDynaBean();
//set the @name property of each bean, user
UPPER to make them distinct
for examples.
root.set(name,ROOT);
animal.set(name,ANIMAL);
dog.set(name,DOG);
cat.set(name,CAT);
boxer.set(name,BOXER);
labrador.set(name,LABRADOR);
tiger1.set(name,TIGER-ONE);
tiger2.set(name,TIGER-TWO);
tiger3.set(name,TIGER-THREE);
lion.set(name,LION);
//build the bean hierarchy.
lazyDynaBean.set(root,0, root);
root.set(animal,0, animal);
animal.set(dog,0,dog);
animal.set(cat,0,cat);
dog.set(labrador,0,labrador);
dog.set(boxer,0, boxer);
cat.set(tiger,0,tiger1);//duplicate
cat.set(tiger,1,tiger2);//duplicate
cat.set(tiger,1,tiger3);//duplicate
cat.set(lion,0,lion);
JXPathContext context =
JXPathContext.newContext(lazyDynaBean);
String query
= /root/animal/cat/tiger;
Object value
= context.getValue(query);
But there's a problem with JXPath querying this
also. Absolute Paths like
'/root/animal/cat/tiger' or
'/root/animal/cat/tiger'[2]' work perfectly.
But I don't have anyluck doing deep searches.
For examples the following
just won't work.
'//cat'
//*...@name='LION']
/root/animal/cat/tig...@name='TIGER-TWO']
Things are looking up, but is this behavior to be
expected?
Cheers,
--AH
On Thu, Feb 12, 2009 at 6:43 AM, Matt Benson
gudnabr...@yahoo.comwrote:
--- On Wed, 2/11/09, Andrew Hughes ahhug...@gmail.com
wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic
Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Wednesday, February 11, 2009, 4:19
AM
Still No Luck, I have removed recursive
generic collections
and have tried
the following code... this is becoming a
marathon effort
:'(
public class Thing {
public
Thing(String name) {
this.name = name;
}
private String
name = ;
public String
getName() {
return name;
}
private
ArrayListThing children = new
ArrayListThing();
public
ArrayListThing getChildren() {
return children;
}
}
public static
void main(String[] args) {
//get some same data
Thing animal = new Thing(Animal);
//Animal.Dog.*
Thing dog = new Thing(Dog);
dog.getChildren().add(new
Thing(Labrador));
dog.getChildren().add(new
Thing(Boxer));
animal.getChildren().add(dog);
//Animal.Cat.*
Thing cat = new Thing(Cat);
cat.getChildren().add(new Thing(Lion));
cat.getChildren().add(new
Thing(Tiger));
animal.getChildren().add(cat);
//run a query on it
JXPathContext context =
JXPathContext.newContext(animal);
String query = /Animal;
Thing result = (Thing)
context.getValue
Re: JXPath over Generic Collection?, How?
And the answer is: In JXPath, a decision was made to overload the name attribute to refer to an element's property name WRT its parent. The reason this was done was to support query maps with non-String keys in JXPath. This means that anytime you actually want to refer to a property whose name literally is name, you must treat it as a child element rather than an attribute. So in your case you could either change name to title and query [...@title='foo'] or simply use [name='foo']. Regards, Matt --- On Mon, 2/23/09, Matt Benson gudnabr...@yahoo.com wrote: From: Matt Benson gudnabr...@yahoo.com Subject: Re: JXPath over Generic Collection?, How? To: Commons Users List user@commons.apache.org Date: Monday, February 23, 2009, 2:58 PM To follow up, the 'name' attribute in particular is what doesn't seem to be working here (change it to e.g. 'game' and it works fine)... if you could file a bug it would help me remember as I don't have time to do it myself right this minute. -Matt --- On Mon, 2/23/09, Matt Benson gudnabr...@yahoo.com wrote: From: Matt Benson gudnabr...@yahoo.com Subject: Re: JXPath over Generic Collection?, How? To: Commons Users List user@commons.apache.org Date: Monday, February 23, 2009, 12:27 PM Andrew, I've been meaning to look into this but haven't yet. If you have any ready-to-run code you can send to the list, that wouldn't hurt... -Matt --- On Mon, 2/23/09, Andrew Hughes ahhug...@gmail.com wrote: From: Andrew Hughes ahhug...@gmail.com Subject: Re: JXPath over Generic Collection?, How? To: Commons Users List user@commons.apache.org Date: Monday, February 23, 2009, 5:42 AM OK, email #19 to the list. I'm both incredibly patient and skeptical that this will ever work. I might try and run this in a debugger and track down how JXPath traverses the DynaBean but given the reflection involved that might be a painful task. --AH On Tue, Feb 17, 2009 at 1:11 PM, Andrew Hughes ahhug...@gmail.com wrote: Ping... if anyone can help with this JXPath DynaBeans problem I'd be REALLY THANKFUL :) On Fri, Feb 13, 2009 at 1:55 PM, Andrew Hughes ahhug...@gmail.com wrote: Howdy, I've taken Matt's suggestion onboard and I have investigated DynaBeans. These look pretty good for all intestive purposes and there's a code examples below how to build the data structure: + root [...@name=ROOT] + animal [...@name=ANIMAL] + dog [...@name=DOG] + boxer [...@name=BOXER] + labrador [...@name=LABRADOR] + cat [...@name=CAT] + tiger [...@name=TIGER-ONE] + tiger [...@name=TIGER-TWO] + tiger [...@name=TIGER-THREE] + lion [...@name=LION] And the code looks like... LazyDynaBean lazyDynaBean = new LazyDynaBean(); //the transparent root. LazyDynaBean root = new LazyDynaBean(); LazyDynaBean animal = new LazyDynaBean(); LazyDynaBean dog = new LazyDynaBean(); LazyDynaBean cat = new LazyDynaBean(); LazyDynaBean boxer = new LazyDynaBean(); LazyDynaBean labrador = new LazyDynaBean(); LazyDynaBean tiger1 = new LazyDynaBean(); LazyDynaBean tiger2 = new LazyDynaBean(); LazyDynaBean tiger3 = new LazyDynaBean(); LazyDynaBean lion = new LazyDynaBean(); //set the @name property of each bean, user UPPER to make them distinct for examples. root.set(name,ROOT); animal.set(name,ANIMAL); dog.set(name,DOG); cat.set(name,CAT); boxer.set(name,BOXER); labrador.set(name,LABRADOR); tiger1.set(name,TIGER-ONE); tiger2.set(name,TIGER-TWO); tiger3.set(name,TIGER-THREE); lion.set(name,LION); //build the bean hierarchy. lazyDynaBean.set(root,0, root); root.set(animal,0, animal); animal.set(dog,0,dog); animal.set(cat,0,cat); dog.set(labrador,0,labrador); dog.set(boxer,0, boxer); cat.set(tiger,0,tiger1);//duplicate cat.set(tiger,1,tiger2);//duplicate cat.set(tiger,1,tiger3);//duplicate cat.set(lion,0,lion); JXPathContext context = JXPathContext.newContext(lazyDynaBean); String query = /root/animal/cat/tiger; Object value = context.getValue(query); But there's a problem with JXPath querying this also. Absolute Paths like '/root/animal/cat/tiger' or '/root/animal/cat/tiger'[2]' work perfectly. But I don't have anyluck doing deep searches. For examples the following just won't work. '//cat' //*...@name='LION'] /root/animal/cat/tig...@name='TIGER-TWO'] Things are looking up, but is this behavior to be expected? Cheers, --AH On Thu, Feb 12, 2009 at 6:43 AM, Matt Benson gudnabr
Re: JXPath over Generic Collection?, How?
I won't get to look at this again at least before tomorrow (9PM for me now and
still have some late-night $work to look at), but I thought I would mention
straight off that the @name feature actually IS mentioned in the userguide
under the section about working with (java.util.)Maps. If you have a
suggestion of where in the guide would be another good place to mention it as a
caveat and/or even the wording to use, feel free to open a documentation issue
in JIRA for it.
TBC,
Matt
--- On Mon, 2/23/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Monday, February 23, 2009, 6:24 PM
Hi Matt,
Thanks HEAPS for you reply, I am really really really
grateful. I think that
I have progressed just a little with this but there are
still some BIG
shortfalls with this. I've attached code that should run
out the box and is
based on previous emails. If I can get the expressions
below to correctly
evaluate I would be heaps happy.
Thanks heaps again, hopefully this will work soon enough.
p.s. I can understand the 'name' vs '@name', perhaps the
userguide could
mention this is about all I can add.
code...
package rnd;
import java.util.ArrayList;
import org.apache.commons.beanutils.LazyDynaBean;
import org.apache.commons.jxpath.JXPathContext;
import org.apache.log4j.Logger;
public class Main {
private static final Logger log =
Logger.getLogger(Main.class);
public static void main(String[] args) {
log.info(Starting...);
LazyDynaBean lazyDynaBean = new LazyDynaBean(); //the
transparent root.
LazyDynaBean root = new LazyDynaBean();
LazyDynaBean animal = new LazyDynaBean();
LazyDynaBean dog = new LazyDynaBean();
LazyDynaBean cat = new LazyDynaBean();
LazyDynaBean boxer = new LazyDynaBean();
LazyDynaBean labrador = new LazyDynaBean();
LazyDynaBean tiger1 = new LazyDynaBean();
LazyDynaBean tiger2 = new LazyDynaBean();
LazyDynaBean tiger3 = new LazyDynaBean();
LazyDynaBean lion = new LazyDynaBean();
//set the @objectName property of each bean, user UPPER to
make them
distinct for examples.
root.set(objectName,ROOT);
animal.set(objectName,ANIMAL);
dog.set(objectName,DOG);
cat.set(objectName,CAT);
boxer.set(objectName,BOXER);
labrador.set(objectName,LABRADOR);
tiger1.set(objectName,TIGER-ONE);
tiger2.set(objectName,TIGER-TWO);
tiger3.set(objectName,TIGER-THREE);
lion.set(objectName,LION);
//build the bean hierarchy.
lazyDynaBean.set(root,0, root);
root.set(animal,0, animal);
animal.set(dog,0,dog);
animal.set(cat,0,cat);
dog.set(labrador,0,labrador);
dog.set(boxer,0, boxer);
cat.set(tiger,0,tiger1);//duplicate
cat.set(tiger,1,tiger2);//duplicate
cat.set(tiger,2,tiger3);//duplicate
cat.set(lion,0,lion);
JXPathContext context =
JXPathContext.newContext(lazyDynaBean);
//these all work
runEvaluation(/root/animal/dog, context); //absolute
single
runEvaluation(/root/animal/cat/tiger[2], context);
//absolute
single
runEvaluation(/root/animal/cat/tiger, context); //absolute
multiple
//everything below fails
runEvaluation(/root/animal/cat/tiger[last()], context);
//absolute
single
runEvaluation(/root/animal/dog/*, context); //absolute
multiple
runEvaluation(//dog,
context); //deep search
runEvaluation(//dog/*,
context);//deep multiple
runEvaluation(//cat/*[objectName='LION'], context);//deep
filter
}
public static void runEvaluation(String
expression,JXPathContext context){
log.info(About to evaulate the expression: +expression);
try {
Object value = context.getValue(expression);
//we got a single result.
if (value instanceof LazyDynaBean) {
LazyDynaBean r =
(LazyDynaBean)context.getValue(expression);
log.info(Ran ' + expression + ' and got objectName=' +
r.get(objectName) + ');
}
//we got multiple results
else if (value instanceof ArrayList) {
String titles = ;
for (LazyDynaBean bean : ((ArrayListLazyDynaBean)
value )){
titles += (bean.get(objectName)+,);
}
log.info(Ran + expression + and got
+((ArrayList)value).size()+
results: +titles);
}
//we got a non-dyna bean.
else {
log.info(Ran ' + expression + ' and got a class ' +
value.getClass().getName() + ' with toString() '
+value.toString() + ');
}
} catch (Exception e) {
log.error(e);
}
}
}
On Tue, Feb 24, 2009 at 8:58 AM, Matt Benson gudnabr...@yahoo.com
wrote:
And the answer is:
In JXPath, a decision was made to overload the
name attribute to refer to
an element's property name WRT its parent. The
reason this was done was
to support query maps with non-String keys in
JXPath. This means that
anytime you actually want to refer to a property whose
name literally is
name, you must treat it as a child element rather
than an attribute. So
in your case you
Re: JXPath over Generic Collection?, How?
Ping... if anyone can help with this JXPath DynaBeans problem I'd be
REALLY THANKFUL :)
On Fri, Feb 13, 2009 at 1:55 PM, Andrew Hughes ahhug...@gmail.com wrote:
Howdy,
I've taken Matt's suggestion onboard and I have investigated DynaBeans.
These look pretty good for all intestive purposes and there's a code
examples below how to build the data structure:
+ root [...@name=ROOT]
+ animal [...@name=ANIMAL]
+ dog [...@name=DOG]
+ boxer [...@name=BOXER]
+ labrador [...@name=LABRADOR]
+ cat [...@name=CAT]
+ tiger [...@name=TIGER-ONE]
+ tiger [...@name=TIGER-TWO]
+ tiger [...@name=TIGER-THREE]
+ lion [...@name=LION]
And the code looks like...
LazyDynaBean lazyDynaBean = new LazyDynaBean(); //the transparent root.
LazyDynaBean root = new LazyDynaBean();
LazyDynaBean animal = new LazyDynaBean();
LazyDynaBean dog = new LazyDynaBean();
LazyDynaBean cat = new LazyDynaBean();
LazyDynaBean boxer = new LazyDynaBean();
LazyDynaBean labrador = new LazyDynaBean();
LazyDynaBean tiger1 = new LazyDynaBean();
LazyDynaBean tiger2 = new LazyDynaBean();
LazyDynaBean tiger3 = new LazyDynaBean();
LazyDynaBean lion = new LazyDynaBean();
//set the @name property of each bean, user UPPER to make them distinct
for examples.
root.set(name,ROOT);
animal.set(name,ANIMAL);
dog.set(name,DOG);
cat.set(name,CAT);
boxer.set(name,BOXER);
labrador.set(name,LABRADOR);
tiger1.set(name,TIGER-ONE);
tiger2.set(name,TIGER-TWO);
tiger3.set(name,TIGER-THREE);
lion.set(name,LION);
//build the bean hierarchy.
lazyDynaBean.set(root,0, root);
root.set(animal,0, animal);
animal.set(dog,0,dog);
animal.set(cat,0,cat);
dog.set(labrador,0,labrador);
dog.set(boxer,0, boxer);
cat.set(tiger,0,tiger1);//duplicate
cat.set(tiger,1,tiger2);//duplicate
cat.set(tiger,1,tiger3);//duplicate
cat.set(lion,0,lion);
JXPathContext context = JXPathContext.newContext(lazyDynaBean);
String query = /root/animal/cat/tiger;
Object value = context.getValue(query);
But there's a problem with JXPath querying this also. Absolute Paths like
'/root/animal/cat/tiger' or '/root/animal/cat/tiger'[2]' work perfectly.
But I don't have anyluck doing deep searches. For examples the following
just won't work.
'//cat'
//*...@name='LION']
/root/animal/cat/tig...@name='TIGER-TWO']
Things are looking up, but is this behavior to be expected?
Cheers,
--AH
On Thu, Feb 12, 2009 at 6:43 AM, Matt Benson gudnabr...@yahoo.com wrote:
--- On Wed, 2/11/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Wednesday, February 11, 2009, 4:19 AM
Still No Luck, I have removed recursive generic collections
and have tried
the following code... this is becoming a marathon effort
:'(
public class Thing {
public Thing(String name) {
this.name = name;
}
private String name = ;
public String getName() {
return name;
}
private ArrayListThing children = new
ArrayListThing();
public ArrayListThing getChildren() {
return children;
}
}
public static void main(String[] args) {
//get some same data
Thing animal = new Thing(Animal);
//Animal.Dog.*
Thing dog = new Thing(Dog);
dog.getChildren().add(new
Thing(Labrador));
dog.getChildren().add(new
Thing(Boxer));
animal.getChildren().add(dog);
//Animal.Cat.*
Thing cat = new Thing(Cat);
cat.getChildren().add(new Thing(Lion));
cat.getChildren().add(new
Thing(Tiger));
animal.getChildren().add(cat);
//run a query on it
JXPathContext context =
JXPathContext.newContext(animal);
String query = /Animal;
Thing result = (Thing) context.getValue(query);
String path = context.getPointer(query).asPath();
System.out.println(Ran ' + query +
' and got ' +
result.getName() + ' on path ' + path +
'.);
}
What would you be trying to select? If you want to know how to look for a
given Thing in this graph, I can probably help. If you want to know what
graph will allow you to use a preconceived notion of the xpath you want to
use, that will be harder. You might use [beanutils] dynabeans in
conjunction with [jxpath] to try and achieve the latter.
-Matt
On Wed, Feb 11, 2009 at 3:08 PM, Andrew Hughes
ahhug...@gmail.com wrote:
Yeah, that makes sense. The part that was confusing me
is that if I
have...
public class Thing {
private ListThing children;
}
I was assuming I would need to prefix all of my
expressions steps with
'/children'. From what you said earlier this
is not the case
Re: JXPath over Generic Collection?, How?
--- On Wed, 2/11/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Wednesday, February 11, 2009, 4:19 AM
Still No Luck, I have removed recursive generic collections
and have tried
the following code... this is becoming a marathon effort
:'(
public class Thing {
public Thing(String name) {
this.name = name;
}
private String name = ;
public String getName() {
return name;
}
private ArrayListThing children = new
ArrayListThing();
public ArrayListThing getChildren() {
return children;
}
}
public static void main(String[] args) {
//get some same data
Thing animal = new Thing(Animal);
//Animal.Dog.*
Thing dog = new Thing(Dog);
dog.getChildren().add(new
Thing(Labrador));
dog.getChildren().add(new
Thing(Boxer));
animal.getChildren().add(dog);
//Animal.Cat.*
Thing cat = new Thing(Cat);
cat.getChildren().add(new Thing(Lion));
cat.getChildren().add(new
Thing(Tiger));
animal.getChildren().add(cat);
//run a query on it
JXPathContext context =
JXPathContext.newContext(animal);
String query = /Animal;
Thing result = (Thing) context.getValue(query);
String path = context.getPointer(query).asPath();
System.out.println(Ran ' + query +
' and got ' +
result.getName() + ' on path ' + path +
'.);
}
What would you be trying to select? If you want to know how to look for a
given Thing in this graph, I can probably help. If you want to know what graph
will allow you to use a preconceived notion of the xpath you want to use, that
will be harder. You might use [beanutils] dynabeans in conjunction with
[jxpath] to try and achieve the latter.
-Matt
On Wed, Feb 11, 2009 at 3:08 PM, Andrew Hughes
ahhug...@gmail.com wrote:
Yeah, that makes sense. The part that was confusing me
is that if I
have...
public class Thing {
private ListThing children;
}
I was assuming I would need to prefix all of my
expressions steps with
'/children'. From what you said earlier this
is not the case as collections
are auto traversed/loaded.
Thanks again matt! I won't get to test this out
til later tonight be look
foward to seeing it working!!!
Andrew
On Wed, Feb 11, 2009 at 2:57 PM, Matt Benson
gudnabr...@yahoo.com wrote:
It should be as simple as Thing _containing_ a
ListThing rather than
_being_ a ListThing. Composition over
inheritance, do you see?
HTH,
Matt
--- On Tue, 2/10/09, Andrew Hughes
ahhug...@gmail.com wrote:
From: Andrew Hughes
ahhug...@gmail.com
Subject: Re: JXPath over Generic
Collection?, How?
To: Commons Users List
user@commons.apache.org,
gudnabr...@yahoo.com
Date: Tuesday, February 10, 2009, 7:06 PM
Matt, Thank You.
Is there any other data structure I can use
that would work
with JXPath? My
requirement is that... a Thing
can have contain
multiple child Thing(s)
(and the children are allowed to be
non-unique).
This is equivalent to an XML element as it
can contain
multiple child
elements, how do these guy's handle it I
wonder?
--Andrew
On Wed, Feb 11, 2009 at 9:09 AM, Matt Benson
gudnabr...@yahoo.com wrote:
I admit I hadn't looked at this with
a highly
critical eye, but this
business of Thing extending
ArrayListThing
seems quite strange to me.
JXPath basically functions by
opening up
collections automatically, so
the very fact that Thing is itself a
Collection
implies that a Thing will be
opened up, and its children will be
searched... but in
this example, either
there are no children, at the leaves, or
the children
themselves are
(possibly empty) collections. It looks
as though
you're trying to represent
a tree structure. This may be a good
example of a
reason for the idea of
composition over inheritance. I
don't think
you're going to get any
traction using JXPath with this object
model.
Sorry for the bad news,
Matt
--- On Tue, 2/10/09, Andrew Hughes
ahhug...@gmail.com wrote:
From: Andrew Hughes
ahhug...@gmail.com
Subject: Re: JXPath over Generic
Collection?, How?
To: Commons Users List
user@commons.apache.org
Date: Tuesday, February 10, 2009,
7:16 AM
Still busted. Example is now
simplified. As soon
as a
generic Collection
becomes involved BOOM!
The Main Method to exec:
public class App {
public static void main(
String[] args ){
JXPathContext context =
JXPathContext.newContext(new
ThingRoot());
System.out.println(((Thing)context.getValue(/root
Re: JXPath over Generic Collection?, How?
I admit I hadn't looked at this with a highly critical eye, but this business
of Thing extending ArrayListThing seems quite strange to me. JXPath
basically functions by opening up collections automatically, so the very fact
that Thing is itself a Collection implies that a Thing will be opened up, and
its children will be searched... but in this example, either there are no
children, at the leaves, or the children themselves are (possibly empty)
collections. It looks as though you're trying to represent a tree structure.
This may be a good example of a reason for the idea of composition over
inheritance. I don't think you're going to get any traction using JXPath with
this object model.
Sorry for the bad news,
Matt
--- On Tue, 2/10/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Tuesday, February 10, 2009, 7:16 AM
Still busted. Example is now simplified. As soon as a
generic Collection
becomes involved BOOM!
The Main Method to exec:
public class App {
public static void main( String[] args ){
JXPathContext context =
JXPathContext.newContext(new ThingRoot());
System.out.println(((Thing)context.getValue(/root)).getName());
}
}
The (populated) context root I am using, where root is a
single object
holding a List of Thing's.
package jxpathresearch;
import java.util.ArrayList;
import java.util.List;
public class ThingRoot {
private ListThing root new ArrayList(); //this
will serve as the root.
public ThingRoot() {
Thing animal = new Thing(Animal);
root.add(animal);//Animal
Thing dog = new Thing(Dog);
animal.add(dog);//Animal.Dog
dog.add(new
Thing(Labrador));//Animal.Dog.Labrador
dog.add(new
Thing(Boxer));//Animal.Dog.Boxer
}
public ListThing getRoot() { return root; }
}
Finally here's a very simple 'Thing' that
contains a List of Thing(s):
public class Thing extends ArrayListThing {
public Thing(String name){this.name = name;}
private String name = ;
public String getName() {return name;}
}
I can't query anything beyond /root, it doesn't
seem to ever get traversed.
I would expect results for //Thing and
//thi...@name='Labrador'] etc but I
get no results only exceptions.
My brain is hurting.
On Tue, Feb 10, 2009 at 12:22 AM, Andrew Hughes
ahhug...@gmail.com wrote:
I've noew tested a whole heap of expressions even
//name='Tiger' nothing
works.
On Tue, Feb 10, 2009 at 12:01 AM, Andrew Hughes
ahhug...@gmail.comwrote:
I got cracking on testing this out... no luck
(yet). Here's my testing
code if some kind person could please take a
look
First my generic collection hierarchy (which only
contains a name and
children)...
package jxpathresearch;
import java.util.ArrayList;
public class HierarchyPojo extends
ArrayListHierarchyPojo {
public HierarchyPojo(String name){
this.setName(name);
}
private String name = ;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Next, the wrapper for the root context (as Matt
suggested) and populated
with animals...
package jxpathresearch;
public class CollectionRoot {
private HierarchyPojo hierarchyPojo;
public CollectionRoot(){
//Animal
hierarchyPojo = new
HierarchyPojo(Animal);
//Animal.Dog
HierarchyPojo dog = new
HierarchyPojo(Dog);
//Animal.Dog.Labrador
dog.add(new
HierarchyPojo(Labrador));
//Animal.Dog.Boxer
dog.add(new
HierarchyPojo(Boxer));
//Animal.Dog.Mastiff
dog.add(new
HierarchyPojo(Mastiff));
//Animal.Cat
HierarchyPojo cat = new
HierarchyPojo(Cat);
//Animal.Cat.Tiger
cat.add(new
HierarchyPojo(Tiger));
//Animal.Cat.Cougar
cat.add(new
HierarchyPojo(Cougar));
//Animal.Cat.Leopard
cat.add(new
HierarchyPojo(Leopard));
//Add Animal.Dog Animal.Cat
hierarchyPojo.add(dog);
hierarchyPojo.add(cat);
}
public HierarchyPojo getHierarchyPojo()
{return hierarchyPojo;}
public void setHierarchyPojo(HierarchyPojo
hierarchyPojo)
{this.hierarchyPojo = hierarchyPojo;}
}
Finally invoke and test...
public class App
{
public static void main( String[] args )
{
JXPathContext context =
JXPathContext.newContext(new
CollectionRoot());
String query =
//hierarchypo...@name='Tiger'];
String fName =
context.getValue(query).toString();
System.out.println(Ran
'+query+' and got
'+fName
Re: JXPath over Generic Collection?, How?
Matt, Thank You.
Is there any other data structure I can use that would work with JXPath? My
requirement is that... a Thing can have contain multiple child Thing(s)
(and the children are allowed to be non-unique).
This is equivalent to an XML element as it can contain multiple child
elements, how do these guy's handle it I wonder?
--Andrew
On Wed, Feb 11, 2009 at 9:09 AM, Matt Benson gudnabr...@yahoo.com wrote:
I admit I hadn't looked at this with a highly critical eye, but this
business of Thing extending ArrayListThing seems quite strange to me.
JXPath basically functions by opening up collections automatically, so
the very fact that Thing is itself a Collection implies that a Thing will be
opened up, and its children will be searched... but in this example, either
there are no children, at the leaves, or the children themselves are
(possibly empty) collections. It looks as though you're trying to represent
a tree structure. This may be a good example of a reason for the idea of
composition over inheritance. I don't think you're going to get any
traction using JXPath with this object model.
Sorry for the bad news,
Matt
--- On Tue, 2/10/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Tuesday, February 10, 2009, 7:16 AM
Still busted. Example is now simplified. As soon as a
generic Collection
becomes involved BOOM!
The Main Method to exec:
public class App {
public static void main( String[] args ){
JXPathContext context =
JXPathContext.newContext(new ThingRoot());
System.out.println(((Thing)context.getValue(/root)).getName());
}
}
The (populated) context root I am using, where root is a
single object
holding a List of Thing's.
package jxpathresearch;
import java.util.ArrayList;
import java.util.List;
public class ThingRoot {
private ListThing root new ArrayList(); //this
will serve as the root.
public ThingRoot() {
Thing animal = new Thing(Animal);
root.add(animal);//Animal
Thing dog = new Thing(Dog);
animal.add(dog);//Animal.Dog
dog.add(new
Thing(Labrador));//Animal.Dog.Labrador
dog.add(new
Thing(Boxer));//Animal.Dog.Boxer
}
public ListThing getRoot() { return root; }
}
Finally here's a very simple 'Thing' that
contains a List of Thing(s):
public class Thing extends ArrayListThing {
public Thing(String name){this.name = name;}
private String name = ;
public String getName() {return name;}
}
I can't query anything beyond /root, it doesn't
seem to ever get traversed.
I would expect results for //Thing and
//thi...@name='Labrador'] etc but I
get no results only exceptions.
My brain is hurting.
On Tue, Feb 10, 2009 at 12:22 AM, Andrew Hughes
ahhug...@gmail.com wrote:
I've noew tested a whole heap of expressions even
//name='Tiger' nothing
works.
On Tue, Feb 10, 2009 at 12:01 AM, Andrew Hughes
ahhug...@gmail.comwrote:
I got cracking on testing this out... no luck
(yet). Here's my testing
code if some kind person could please take a
look
First my generic collection hierarchy (which only
contains a name and
children)...
package jxpathresearch;
import java.util.ArrayList;
public class HierarchyPojo extends
ArrayListHierarchyPojo {
public HierarchyPojo(String name){
this.setName(name);
}
private String name = ;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Next, the wrapper for the root context (as Matt
suggested) and populated
with animals...
package jxpathresearch;
public class CollectionRoot {
private HierarchyPojo hierarchyPojo;
public CollectionRoot(){
//Animal
hierarchyPojo = new
HierarchyPojo(Animal);
//Animal.Dog
HierarchyPojo dog = new
HierarchyPojo(Dog);
//Animal.Dog.Labrador
dog.add(new
HierarchyPojo(Labrador));
//Animal.Dog.Boxer
dog.add(new
HierarchyPojo(Boxer));
//Animal.Dog.Mastiff
dog.add(new
HierarchyPojo(Mastiff));
//Animal.Cat
HierarchyPojo cat = new
HierarchyPojo(Cat);
//Animal.Cat.Tiger
cat.add(new
HierarchyPojo(Tiger));
//Animal.Cat.Cougar
cat.add(new
HierarchyPojo(Cougar));
//Animal.Cat.Leopard
cat.add(new
HierarchyPojo(Leopard));
//Add Animal.Dog Animal.Cat
hierarchyPojo.add(dog);
hierarchyPojo.add(cat);
}
public
Re: JXPath over Generic Collection?, How?
It should be as simple as Thing _containing_ a ListThing rather than _being_
a ListThing. Composition over inheritance, do you see?
HTH,
Matt
--- On Tue, 2/10/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org, gudnabr...@yahoo.com
Date: Tuesday, February 10, 2009, 7:06 PM
Matt, Thank You.
Is there any other data structure I can use that would work
with JXPath? My
requirement is that... a Thing can have contain
multiple child Thing(s)
(and the children are allowed to be non-unique).
This is equivalent to an XML element as it can contain
multiple child
elements, how do these guy's handle it I wonder?
--Andrew
On Wed, Feb 11, 2009 at 9:09 AM, Matt Benson
gudnabr...@yahoo.com wrote:
I admit I hadn't looked at this with a highly
critical eye, but this
business of Thing extending ArrayListThing
seems quite strange to me.
JXPath basically functions by opening up
collections automatically, so
the very fact that Thing is itself a Collection
implies that a Thing will be
opened up, and its children will be searched... but in
this example, either
there are no children, at the leaves, or the children
themselves are
(possibly empty) collections. It looks as though
you're trying to represent
a tree structure. This may be a good example of a
reason for the idea of
composition over inheritance. I don't think
you're going to get any
traction using JXPath with this object model.
Sorry for the bad news,
Matt
--- On Tue, 2/10/09, Andrew Hughes
ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic
Collection?, How?
To: Commons Users List
user@commons.apache.org
Date: Tuesday, February 10, 2009, 7:16 AM
Still busted. Example is now simplified. As soon
as a
generic Collection
becomes involved BOOM!
The Main Method to exec:
public class App {
public static void main( String[] args ){
JXPathContext context =
JXPathContext.newContext(new ThingRoot());
System.out.println(((Thing)context.getValue(/root)).getName());
}
}
The (populated) context root I am using, where
root is a
single object
holding a List of Thing's.
package jxpathresearch;
import java.util.ArrayList;
import java.util.List;
public class ThingRoot {
private ListThing root new
ArrayList(); //this
will serve as the root.
public ThingRoot() {
Thing animal = new
Thing(Animal);
root.add(animal);//Animal
Thing dog = new Thing(Dog);
animal.add(dog);//Animal.Dog
dog.add(new
Thing(Labrador));//Animal.Dog.Labrador
dog.add(new
Thing(Boxer));//Animal.Dog.Boxer
}
public ListThing getRoot() { return
root; }
}
Finally here's a very simple 'Thing'
that
contains a List of Thing(s):
public class Thing extends ArrayListThing
{
public Thing(String name){this.name = name;}
private String name = ;
public String getName() {return name;}
}
I can't query anything beyond /root, it
doesn't
seem to ever get traversed.
I would expect results for //Thing and
//thi...@name='Labrador'] etc but I
get no results only exceptions.
My brain is hurting.
On Tue, Feb 10, 2009 at 12:22 AM, Andrew Hughes
ahhug...@gmail.com wrote:
I've noew tested a whole heap of
expressions even
//name='Tiger' nothing
works.
On Tue, Feb 10, 2009 at 12:01 AM, Andrew
Hughes
ahhug...@gmail.comwrote:
I got cracking on testing this out... no
luck
(yet). Here's my testing
code if some kind person could please
take a
look
First my generic collection hierarchy
(which only
contains a name and
children)...
package jxpathresearch;
import java.util.ArrayList;
public class HierarchyPojo extends
ArrayListHierarchyPojo {
public HierarchyPojo(String name){
this.setName(name);
}
private String name = ;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Next, the wrapper for the root context
(as Matt
suggested) and populated
with animals...
package jxpathresearch;
public class CollectionRoot {
private HierarchyPojo hierarchyPojo;
public CollectionRoot(){
//Animal
hierarchyPojo = new
HierarchyPojo(Animal);
//Animal.Dog
HierarchyPojo dog = new
HierarchyPojo(Dog);
//Animal.Dog.Labrador
dog.add(new
HierarchyPojo(Labrador));
//Animal.Dog.Boxer
dog.add(new
Re: JXPath over Generic Collection?, How?
Yeah, that makes sense. The part that was confusing me is that if I have...
public class Thing {
private ListThing children;
}
I was assuming I would need to prefix all of my expressions steps with
'/children'. From what you said earlier this is not the case as collections
are auto traversed/loaded.
Thanks again matt! I won't get to test this out til later tonight be look
foward to seeing it working!!!
Andrew
On Wed, Feb 11, 2009 at 2:57 PM, Matt Benson gudnabr...@yahoo.com wrote:
It should be as simple as Thing _containing_ a ListThing rather than
_being_ a ListThing. Composition over inheritance, do you see?
HTH,
Matt
--- On Tue, 2/10/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org, gudnabr...@yahoo.com
Date: Tuesday, February 10, 2009, 7:06 PM
Matt, Thank You.
Is there any other data structure I can use that would work
with JXPath? My
requirement is that... a Thing can have contain
multiple child Thing(s)
(and the children are allowed to be non-unique).
This is equivalent to an XML element as it can contain
multiple child
elements, how do these guy's handle it I wonder?
--Andrew
On Wed, Feb 11, 2009 at 9:09 AM, Matt Benson
gudnabr...@yahoo.com wrote:
I admit I hadn't looked at this with a highly
critical eye, but this
business of Thing extending ArrayListThing
seems quite strange to me.
JXPath basically functions by opening up
collections automatically, so
the very fact that Thing is itself a Collection
implies that a Thing will be
opened up, and its children will be searched... but in
this example, either
there are no children, at the leaves, or the children
themselves are
(possibly empty) collections. It looks as though
you're trying to represent
a tree structure. This may be a good example of a
reason for the idea of
composition over inheritance. I don't think
you're going to get any
traction using JXPath with this object model.
Sorry for the bad news,
Matt
--- On Tue, 2/10/09, Andrew Hughes
ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: Re: JXPath over Generic
Collection?, How?
To: Commons Users List
user@commons.apache.org
Date: Tuesday, February 10, 2009, 7:16 AM
Still busted. Example is now simplified. As soon
as a
generic Collection
becomes involved BOOM!
The Main Method to exec:
public class App {
public static void main( String[] args ){
JXPathContext context =
JXPathContext.newContext(new ThingRoot());
System.out.println(((Thing)context.getValue(/root)).getName());
}
}
The (populated) context root I am using, where
root is a
single object
holding a List of Thing's.
package jxpathresearch;
import java.util.ArrayList;
import java.util.List;
public class ThingRoot {
private ListThing root new
ArrayList(); //this
will serve as the root.
public ThingRoot() {
Thing animal = new
Thing(Animal);
root.add(animal);//Animal
Thing dog = new Thing(Dog);
animal.add(dog);//Animal.Dog
dog.add(new
Thing(Labrador));//Animal.Dog.Labrador
dog.add(new
Thing(Boxer));//Animal.Dog.Boxer
}
public ListThing getRoot() { return
root; }
}
Finally here's a very simple 'Thing'
that
contains a List of Thing(s):
public class Thing extends ArrayListThing
{
public Thing(String name){this.name = name;}
private String name = ;
public String getName() {return name;}
}
I can't query anything beyond /root, it
doesn't
seem to ever get traversed.
I would expect results for //Thing and
//thi...@name='Labrador'] etc but I
get no results only exceptions.
My brain is hurting.
On Tue, Feb 10, 2009 at 12:22 AM, Andrew Hughes
ahhug...@gmail.com wrote:
I've noew tested a whole heap of
expressions even
//name='Tiger' nothing
works.
On Tue, Feb 10, 2009 at 12:01 AM, Andrew
Hughes
ahhug...@gmail.comwrote:
I got cracking on testing this out... no
luck
(yet). Here's my testing
code if some kind person could please
take a
look
First my generic collection hierarchy
(which only
contains a name and
children)...
package jxpathresearch;
import java.util.ArrayList;
public class HierarchyPojo extends
ArrayListHierarchyPojo {
public HierarchyPojo(String name){
this.setName(name);
}
private String name = ;
public String getName() {
return name;
}
public void setName(String name
Re: JXPath over Generic Collection?, How?
I got cracking on testing this out... no luck (yet). Here's my testing code
if some kind person could please take a look
First my generic collection hierarchy (which only contains a name and
children)...
package jxpathresearch;
import java.util.ArrayList;
public class HierarchyPojo extends ArrayListHierarchyPojo {
public HierarchyPojo(String name){
this.setName(name);
}
private String name = ;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Next, the wrapper for the root context (as Matt suggested) and populated
with animals...
package jxpathresearch;
public class CollectionRoot {
private HierarchyPojo hierarchyPojo;
public CollectionRoot(){
//Animal
hierarchyPojo = new HierarchyPojo(Animal);
//Animal.Dog
HierarchyPojo dog = new HierarchyPojo(Dog);
//Animal.Dog.Labrador
dog.add(new HierarchyPojo(Labrador));
//Animal.Dog.Boxer
dog.add(new HierarchyPojo(Boxer));
//Animal.Dog.Mastiff
dog.add(new HierarchyPojo(Mastiff));
//Animal.Cat
HierarchyPojo cat = new HierarchyPojo(Cat);
//Animal.Cat.Tiger
cat.add(new HierarchyPojo(Tiger));
//Animal.Cat.Cougar
cat.add(new HierarchyPojo(Cougar));
//Animal.Cat.Leopard
cat.add(new HierarchyPojo(Leopard));
//Add Animal.Dog Animal.Cat
hierarchyPojo.add(dog);
hierarchyPojo.add(cat);
}
public HierarchyPojo getHierarchyPojo() {return hierarchyPojo;}
public void setHierarchyPojo(HierarchyPojo hierarchyPojo)
{this.hierarchyPojo = hierarchyPojo;}
}
Finally invoke and test...
public class App
{
public static void main( String[] args )
{
JXPathContext context = JXPathContext.newContext(new
CollectionRoot());
String query = //hierarchypo...@name='Tiger'];
String fName = context.getValue(query).toString();
System.out.println(Ran '+query+' and got '+fName+');
}
}
Above, should find one entry for 'name=Tiger' but it does not, I get an
exception. This still doesn't seem to traverse the Collection correctly. Any
help would be most welcome.
Exception in thread main
org.apache.commons.jxpath.JXPathNotFoundException: No value for xpath:
//hierarchypo...@name='Tiger']
Thanks for reading,
Andrew
On Mon, Feb 9, 2009 at 10:24 PM, Andrew Hughes ahhug...@gmail.com wrote:
Thanks Matt - I will test this out tomorrow when I am back in the office...
Being constructive...
Surely this should at least be a precondition check and throw a specific
exception if it's not supported?
Thank You
--Andrew
On Mon, Feb 9, 2009 at 2:27 PM, Matt Benson gudnabr...@yahoo.com wrote:
Most likely your problem is not with generics, but simply with the fact
that JXPath has a hard time using a collection as its root. The easiest
workaround is to use some parent object to hold a reference to your
container.
HTH,
Matt
--- On Sun, 2/8/09, Andrew Hughes ahhug...@gmail.com wrote:
From: Andrew Hughes ahhug...@gmail.com
Subject: JXPath over Generic Collection?, How?
To: Commons Users List user@commons.apache.org
Date: Sunday, February 8, 2009, 5:09 PM
Hi All,
Hopefully the solution is as easy as the question. I would
like to perform
evaluation on a (very simple) generic collection... as you
can see below
(HeirarchyPojo). I should be able to ask for a
HeirarchyPojo's with
name='Bill' or the 3rd Child... The problem is that
nothing ever evaluate on
this data structure. What's the deal with Generic
Collections and JXPath?
p.s this is not in the userguide and would be a most
welcomed addition (if
we can nut this out with your help).
Cheers.
package xpath.and.generics;
import java.util.ArrayList;
public class HeirarchyPojo extends
ArrayListHeirarchyPojo{
public HeirarchyPojo(){}
private String id;
private String name;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
-
To unsubscribe, e-mail: user-unsubscr...@commons.apache.org
For additional commands, e-mail: user-h...@commons.apache.org
JXPath over Generic Collection?, How?
Hi All,
Hopefully the solution is as easy as the question. I would like to perform
evaluation on a (very simple) generic collection... as you can see below
(HeirarchyPojo). I should be able to ask for a HeirarchyPojo's with
name='Bill' or the 3rd Child... The problem is that nothing ever evaluate on
this data structure. What's the deal with Generic Collections and JXPath?
p.s this is not in the userguide and would be a most welcomed addition (if
we can nut this out with your help).
Cheers.
package xpath.and.generics;
import java.util.ArrayList;
public class HeirarchyPojo extends ArrayListHeirarchyPojo{
public HeirarchyPojo(){}
private String id;
private String name;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
