Re: Problem in saving class instances to file

[Martynas Jusevičius]

Where is the code??

On Fri, Dec 2, 2016 at 2:23 PM, kumar rohit  wrote:
> Hello Lorenz, I tried to load the model from one owl file and then stored
> it to another file (though both files have same data, but different names).
> When I try to load model from owl file and store also into same file, it
> then works fine and data is not overwritten.
>
>
>
> On Fri, Dec 2, 2016 at 2:00 PM, Lorenz B. <
> buehm...@informatik.uni-leipzig.de> wrote:
>
>>
>> > If you really want to write each user to a separate file
>> >
>> > I dont want each user to a separate file, rather I want to save all the
>> > individuals/students in one file. Some times ago, it worked for me but I
>> > have made some changes to my code and now when I enter an individual, it
>> > replaces the existing one and hence saves only one at a time.
>> >
>> > I have checked the model before saving it to a file, and the model
>> contains
>> > only one individual (replaces existing one), so I think the problem is
>> not
>> > in the file saving itself.
>> As I said, you have to load the existing model from the existing file.
>> Then work on this model. Then save this model to disk to the same file.
>> >
>> >
>> >
>> > On Fri, Dec 2, 2016 at 12:23 PM, Claude Warren  wrote:
>> >
>> >> It sounds to me like Kumar is thinking that he needs to store each
>> student
>> >> in an individual file and load that.  Kumar, if that is the case then I
>> >> think you misunderstand how the graph storage works.  Or you have an
>> >> unusual use case.  In most cases you would simply write the entire
>> graph to
>> >> disk (Ususally using TDB as the storage engine as it will handle all the
>> >> persistence for you).  If you really want to write each user to a
>> separate
>> >> file then I would suggest creating a model using the Construct select to
>> >> pull all the data about the user and then write that graph to disk using
>> >> the standard graph.write() functionality.
>> >>
>> >> Claude
>> >>
>> >> On Fri, Dec 2, 2016 at 8:18 AM, Lorenz B. <
>> >> buehm...@informatik.uni-leipzig.de> wrote:
>> >>
>> >>>
>>  Hi
>>  I want to create student instances of my Student class and enter his
>>  details. Then at the end I writes model to the file.
>> 
>>   OntClass std = model.getOntClass(ns + "Student");
>>    Individual mystd = std.createIndividual(ns + stdname);
>> 
>>  In the file when I enter name of a student, i-e Bob, it saves to the
>> >> file
>>  along other information like department, address etc.
>>  Next time, when I enter another student name, i-e Alice, it replaces
>>  previous instances of students and currently only one student is saved
>> >> to
>>  file.
>> 
>>  I want record of all students so need all student instances. I used
>> for
>>  file writing.
>> >>> I don't understand the problem. You have to load the existing model and
>> >>> add new individuals to it. If you don't open the existing model, indeed
>> >>> only what's added to your new model will be saved to the file.
>>  try (FileOutputStream write = new FileOutputStream("D://
>> >> students.owl"))
>> >>> {
>> model.write(write, "RDF/XML");
>> 
>> >>> --
>> >>> Lorenz Bühmann
>> >>> AKSW group, University of Leipzig
>> >>> Group: http://aksw.org - semantic web research center
>> >>>
>> >>>
>> >>
>> >> --
>> >> I like: Like Like - The likeliest place on the web
>> >> 
>> >> LinkedIn: http://www.linkedin.com/in/claudewarren
>> >>
>> --
>> Lorenz Bühmann
>> AKSW group, University of Leipzig
>> Group: http://aksw.org - semantic web research center
>>
>>

Re: Problem in saving class instances to file

[kumar rohit]

Hello Lorenz, I tried to load the model from one owl file and then stored
it to another file (though both files have same data, but different names).
When I try to load model from owl file and store also into same file, it
then works fine and data is not overwritten.



On Fri, Dec 2, 2016 at 2:00 PM, Lorenz B. <
buehm...@informatik.uni-leipzig.de> wrote:

>
> > If you really want to write each user to a separate file
> >
> > I dont want each user to a separate file, rather I want to save all the
> > individuals/students in one file. Some times ago, it worked for me but I
> > have made some changes to my code and now when I enter an individual, it
> > replaces the existing one and hence saves only one at a time.
> >
> > I have checked the model before saving it to a file, and the model
> contains
> > only one individual (replaces existing one), so I think the problem is
> not
> > in the file saving itself.
> As I said, you have to load the existing model from the existing file.
> Then work on this model. Then save this model to disk to the same file.
> >
> >
> >
> > On Fri, Dec 2, 2016 at 12:23 PM, Claude Warren  wrote:
> >
> >> It sounds to me like Kumar is thinking that he needs to store each
> student
> >> in an individual file and load that.  Kumar, if that is the case then I
> >> think you misunderstand how the graph storage works.  Or you have an
> >> unusual use case.  In most cases you would simply write the entire
> graph to
> >> disk (Ususally using TDB as the storage engine as it will handle all the
> >> persistence for you).  If you really want to write each user to a
> separate
> >> file then I would suggest creating a model using the Construct select to
> >> pull all the data about the user and then write that graph to disk using
> >> the standard graph.write() functionality.
> >>
> >> Claude
> >>
> >> On Fri, Dec 2, 2016 at 8:18 AM, Lorenz B. <
> >> buehm...@informatik.uni-leipzig.de> wrote:
> >>
> >>>
>  Hi
>  I want to create student instances of my Student class and enter his
>  details. Then at the end I writes model to the file.
> 
>   OntClass std = model.getOntClass(ns + "Student");
>    Individual mystd = std.createIndividual(ns + stdname);
> 
>  In the file when I enter name of a student, i-e Bob, it saves to the
> >> file
>  along other information like department, address etc.
>  Next time, when I enter another student name, i-e Alice, it replaces
>  previous instances of students and currently only one student is saved
> >> to
>  file.
> 
>  I want record of all students so need all student instances. I used
> for
>  file writing.
> >>> I don't understand the problem. You have to load the existing model and
> >>> add new individuals to it. If you don't open the existing model, indeed
> >>> only what's added to your new model will be saved to the file.
>  try (FileOutputStream write = new FileOutputStream("D://
> >> students.owl"))
> >>> {
> model.write(write, "RDF/XML");
> 
> >>> --
> >>> Lorenz Bühmann
> >>> AKSW group, University of Leipzig
> >>> Group: http://aksw.org - semantic web research center
> >>>
> >>>
> >>
> >> --
> >> I like: Like Like - The likeliest place on the web
> >> 
> >> LinkedIn: http://www.linkedin.com/in/claudewarren
> >>
> --
> Lorenz Bühmann
> AKSW group, University of Leipzig
> Group: http://aksw.org - semantic web research center
>
>

Re: Problem in saving class instances to file

[Lorenz B.]

> If you really want to write each user to a separate file
>
> I dont want each user to a separate file, rather I want to save all the
> individuals/students in one file. Some times ago, it worked for me but I
> have made some changes to my code and now when I enter an individual, it
> replaces the existing one and hence saves only one at a time.
>
> I have checked the model before saving it to a file, and the model contains
> only one individual (replaces existing one), so I think the problem is not
> in the file saving itself.
As I said, you have to load the existing model from the existing file.
Then work on this model. Then save this model to disk to the same file.
>
>
>
> On Fri, Dec 2, 2016 at 12:23 PM, Claude Warren  wrote:
>
>> It sounds to me like Kumar is thinking that he needs to store each student
>> in an individual file and load that.  Kumar, if that is the case then I
>> think you misunderstand how the graph storage works.  Or you have an
>> unusual use case.  In most cases you would simply write the entire graph to
>> disk (Ususally using TDB as the storage engine as it will handle all the
>> persistence for you).  If you really want to write each user to a separate
>> file then I would suggest creating a model using the Construct select to
>> pull all the data about the user and then write that graph to disk using
>> the standard graph.write() functionality.
>>
>> Claude
>>
>> On Fri, Dec 2, 2016 at 8:18 AM, Lorenz B. <
>> buehm...@informatik.uni-leipzig.de> wrote:
>>
>>>
 Hi
 I want to create student instances of my Student class and enter his
 details. Then at the end I writes model to the file.

  OntClass std = model.getOntClass(ns + "Student");
   Individual mystd = std.createIndividual(ns + stdname);

 In the file when I enter name of a student, i-e Bob, it saves to the
>> file
 along other information like department, address etc.
 Next time, when I enter another student name, i-e Alice, it replaces
 previous instances of students and currently only one student is saved
>> to
 file.

 I want record of all students so need all student instances. I used for
 file writing.
>>> I don't understand the problem. You have to load the existing model and
>>> add new individuals to it. If you don't open the existing model, indeed
>>> only what's added to your new model will be saved to the file.
 try (FileOutputStream write = new FileOutputStream("D://
>> students.owl"))
>>> {
model.write(write, "RDF/XML");

>>> --
>>> Lorenz Bühmann
>>> AKSW group, University of Leipzig
>>> Group: http://aksw.org - semantic web research center
>>>
>>>
>>
>> --
>> I like: Like Like - The likeliest place on the web
>> 
>> LinkedIn: http://www.linkedin.com/in/claudewarren
>>
-- 
Lorenz Bühmann
AKSW group, University of Leipzig
Group: http://aksw.org - semantic web research center

Re: Problem in saving class instances to file

[kumar rohit]

If you really want to write each user to a separate file

I dont want each user to a separate file, rather I want to save all the
individuals/students in one file. Some times ago, it worked for me but I
have made some changes to my code and now when I enter an individual, it
replaces the existing one and hence saves only one at a time.

I have checked the model before saving it to a file, and the model contains
only one individual (replaces existing one), so I think the problem is not
in the file saving itself.



On Fri, Dec 2, 2016 at 12:23 PM, Claude Warren  wrote:

> It sounds to me like Kumar is thinking that he needs to store each student
> in an individual file and load that.  Kumar, if that is the case then I
> think you misunderstand how the graph storage works.  Or you have an
> unusual use case.  In most cases you would simply write the entire graph to
> disk (Ususally using TDB as the storage engine as it will handle all the
> persistence for you).  If you really want to write each user to a separate
> file then I would suggest creating a model using the Construct select to
> pull all the data about the user and then write that graph to disk using
> the standard graph.write() functionality.
>
> Claude
>
> On Fri, Dec 2, 2016 at 8:18 AM, Lorenz B. <
> buehm...@informatik.uni-leipzig.de> wrote:
>
> >
> >
> > > Hi
> > > I want to create student instances of my Student class and enter his
> > > details. Then at the end I writes model to the file.
> > >
> > >  OntClass std = model.getOntClass(ns + "Student");
> > >   Individual mystd = std.createIndividual(ns + stdname);
> > >
> > > In the file when I enter name of a student, i-e Bob, it saves to the
> file
> > > along other information like department, address etc.
> > > Next time, when I enter another student name, i-e Alice, it replaces
> > > previous instances of students and currently only one student is saved
> to
> > > file.
> > >
> > > I want record of all students so need all student instances. I used for
> > > file writing.
> > I don't understand the problem. You have to load the existing model and
> > add new individuals to it. If you don't open the existing model, indeed
> > only what's added to your new model will be saved to the file.
> > > try (FileOutputStream write = new FileOutputStream("D://
> students.owl"))
> > {
> > >model.write(write, "RDF/XML");
> > >
> > --
> > Lorenz Bühmann
> > AKSW group, University of Leipzig
> > Group: http://aksw.org - semantic web research center
> >
> >
>
>
> --
> I like: Like Like - The likeliest place on the web
> 
> LinkedIn: http://www.linkedin.com/in/claudewarren
>

Re: Problem in saving class instances to file

[Claude Warren]

It sounds to me like Kumar is thinking that he needs to store each student
in an individual file and load that.  Kumar, if that is the case then I
think you misunderstand how the graph storage works.  Or you have an
unusual use case.  In most cases you would simply write the entire graph to
disk (Ususally using TDB as the storage engine as it will handle all the
persistence for you).  If you really want to write each user to a separate
file then I would suggest creating a model using the Construct select to
pull all the data about the user and then write that graph to disk using
the standard graph.write() functionality.

Claude

On Fri, Dec 2, 2016 at 8:18 AM, Lorenz B. <
buehm...@informatik.uni-leipzig.de> wrote:

>
>
> > Hi
> > I want to create student instances of my Student class and enter his
> > details. Then at the end I writes model to the file.
> >
> >  OntClass std = model.getOntClass(ns + "Student");
> >   Individual mystd = std.createIndividual(ns + stdname);
> >
> > In the file when I enter name of a student, i-e Bob, it saves to the file
> > along other information like department, address etc.
> > Next time, when I enter another student name, i-e Alice, it replaces
> > previous instances of students and currently only one student is saved to
> > file.
> >
> > I want record of all students so need all student instances. I used for
> > file writing.
> I don't understand the problem. You have to load the existing model and
> add new individuals to it. If you don't open the existing model, indeed
> only what's added to your new model will be saved to the file.
> > try (FileOutputStream write = new FileOutputStream("D://students.owl"))
> {
> >model.write(write, "RDF/XML");
> >
> --
> Lorenz Bühmann
> AKSW group, University of Leipzig
> Group: http://aksw.org - semantic web research center
>
>


-- 
I like: Like Like - The likeliest place on the web

LinkedIn: http://www.linkedin.com/in/claudewarren

Re: Problem in saving class instances to file

[Lorenz B.]

> Hi
> I want to create student instances of my Student class and enter his
> details. Then at the end I writes model to the file.
>
>  OntClass std = model.getOntClass(ns + "Student");
>   Individual mystd = std.createIndividual(ns + stdname);
>
> In the file when I enter name of a student, i-e Bob, it saves to the file
> along other information like department, address etc.
> Next time, when I enter another student name, i-e Alice, it replaces
> previous instances of students and currently only one student is saved to
> file.
>
> I want record of all students so need all student instances. I used for
> file writing.
I don't understand the problem. You have to load the existing model and
add new individuals to it. If you don't open the existing model, indeed
only what's added to your new model will be saved to the file.
> try (FileOutputStream write = new FileOutputStream("D://students.owl")) {
>model.write(write, "RDF/XML");
>
-- 
Lorenz Bühmann
AKSW group, University of Leipzig
Group: http://aksw.org - semantic web research center

Problem in saving class instances to file

[kumar rohit]

Hi
I want to create student instances of my Student class and enter his
details. Then at the end I writes model to the file.

 OntClass std = model.getOntClass(ns + "Student");
  Individual mystd = std.createIndividual(ns + stdname);

In the file when I enter name of a student, i-e Bob, it saves to the file
along other information like department, address etc.
Next time, when I enter another student name, i-e Alice, it replaces
previous instances of students and currently only one student is saved to
file.

I want record of all students so need all student instances. I used for
file writing.

try (FileOutputStream write = new FileOutputStream("D://students.owl")) {
   model.write(write, "RDF/XML");