Java

Re: how to read large 8gb json text file in java program

26-Jan-16 22:35

If you are trying to read all that much data into memory then it will never work. You need to read it in smaller blocks and process only the data you can hold in memory.

markkuk27-Jan-16 1:43

markkuk

27-Jan-16 1:43

Use the JSON Processing API[^] instead of trying to write your own parser from scratch. Use the Streaming API[^] so that you don't need to read the whole file into memory.

How to using jena lib with rdf for semantic web.

Fatih Khoirul Umam19-Jan-16 14:14

Fatih Khoirul Umam

19-Jan-16 14:14

I'm using jena lib to translate rdf to java, but i have problem, how to get some property in java code using loop and i have array to save them. Thank you for your answer Smile | :)

This is my rdf code.
<rdf:RDF
xmlns:rdf='http://www.w3.org/1999/02/22-rdf-syntax-ns#'
xmlns:vCard='http://www.w3.org/2001/vcard-rdf/3.0#'
>

<rdf:Description rdf:about="http://somewhere/JohnSmith/">
<vCard:FN>John Smith</vCard:FN>
<vCard:N rdf:parseType="Resource">
<vCard:Family>Smith</vCard:Family>
<vCard:Given>John</vCard:Given>
</vCard:N>
</rdf:Description>

<rdf:Description rdf:about="http://somewhere/RebeccaSmith/">
<vCard:FN>Becky Smith</vCard:FN>
<vCard:N rdf:parseType="Resource">
<vCard:Family>Smith</vCard:Family>
<vCard:Given>Rebecca</vCard:Given>
</vCard:N>
</rdf:Description>

</rdf:RDF>

Re: How to using jena lib with rdf for semantic web.

Richard MacCutchan19-Jan-16 23:15

As regards the voice chat in spark im.

19-Jan-16 23:15

It is not clear what your problem is. The above would appear to be some XML formatted data, so you can use the XMLReader (Java Platform SE 7 )[^] to extract the fields from it.

superman_kgy16-Jan-16 4:41

superman_kgy

16-Jan-16 4:41

The spark of current version is used FMJ library as media library,
and so the voice chatting can't progress.
If the libjitsi library replace fmj, I don't know it to be impossible.

Re: As regards the voice chat in spark im.

Richard MacCutchan16-Jan-16 4:44

how to calculate 4 year degree completed data in resume

16-Jan-16 4:44

See Media Library - FMJ[^] and libjitsi | Jitsi[^].

Member 1216598516-Jan-16 0:34

Member 12165985

16-Jan-16 0:34

I have one large json file in that each cv have two or more degree ie mention.

I want data that having 4 year degree is completed How to do that using java code.

in degree any thing mention like BA ,BCOm ,BS,MBA, MS, BE ,ME but I want those data having 4 year degree completed how to do that ?

Suppose In CV :::BA ,BCOm ,BS,MBA, MS, BE ,ME
these are the degree

Output is BE Because is 4 year other are 3 year 0r 2 year I want only 4 year completed how to do that ?

In Cv there are lot of other degree so how to calculate exact 4 year completed degree ?
is there nay idea ?

Re: how to calculate 4 year degree completed data in resume

Peter Leow16-Jan-16 0:50

Peter Leow

16-Jan-16 0:50

How did you tell BE is 4-year degree? There isn't enough information. You have to add one more piece of information say "length of study" for each degree.

Peter Leow
https://www.amazon.com/author/peterleow

Re: how to calculate 4 year degree completed data in resume

Richard MacCutchan16-Jan-16 2:33

16-Jan-16 2:33

There is no way to do it with just those letters, as they could mean anything.

print jPanel

Member 122400217-Jan-16 23:27

Member 12240021

7-Jan-16 23:27

Hello,
I have an application that needs to print the contents of a JPanel, and I using this code

Java

PrinterJob job = PrinterJob.getPrinterJob();
job.setPrintable(new Printable() {
 
            @Override
            public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException {
                if (pageIndex > 0) {
            return NO_SUCH_PAGE;
        }
         
        int marge=30;
        int x = (int)pageFormat.getImageableX();
        int y = (int)pageFormat.getImageableY();
                 
        graphics.setFont(new Font("Times new roman", Font.BOLD, 14));
        graphics.setColor(Color.BLACK);
        graphics.drawString("ACTE DEMANDER\n", x + marge, y + marge);
 
panel.print(graphics);;           
 
        return PAGE_EXISTS;
            }
 
        });
boolean doPrint = job.printDialog();
if(doPrint) {
    try {
         
        job.print();
    }
    catch (PrinterException e1) {
            JOptionPane.showMessageDialog(null, e1);
    }
}

and it works well, but that code display the border of JTextArea, which is supposed to be borderless after being printed and the content of this JTextArea are not all displayed texts are cut.
So I decided to print one by one the contents of this JPanel but its content does not switch to the line as I did in my interface but it is superimposed one above the other.
this is my second code

Java

PrinterJob job = PrinterJob.getPrinterJob();
job.setPrintable(new Printable() {
 
            @Override
            public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException {
                if (pageIndex > 0) {
            return NO_SUCH_PAGE;
        }
         
        int marge=30;
        int x = (int)pageFormat.getImageableX();
        int y = (int)pageFormat.getImageableY();
                 
        graphics.setFont(new Font("Times new roman", Font.BOLD, 14));
        graphics.setColor(Color.BLACK);
        graphics.drawString("ACTE DEMANDER\n", x + marge, y + marge);
 
jLabel1.print(graphics);
jLabel2.print(graphics);
jLabel3.print(graphics);
jTextArea1.print(graphics);
jTextPane1.print(graphics);           
 
        return PAGE_EXISTS;
            }
 
        });
boolean doPrint = job.printDialog();
if(doPrint) {
    try {
         
        job.print();
    }
    catch (PrinterException e1) {
            JOptionPane.showMessageDialog(null, e1);
    }
}

How then could I do to make them lines or retrieve the contents of my JTextArea whatever the length of the text and there is newline. All help in both cases are welcome.
thank you for helping me
Best regards.

Re: print jPanel

Richard MacCutchan8-Jan-16 1:17

8-Jan-16 1:17

You need to move the cursor down the page after printing each item. See Lesson: Printing (The Java™ Tutorials > 2D Graphics)[^].

mini game in java

Member 113848203-Jan-16 20:20

Member 11384820

3-Jan-16 20:20

You define a
discrete random variable X that assumes values represent your awards and losses when you play the
game. For simplicity, assume that the awards are positive and the losses are negative. Each award
or a loss is associated with a probability. You run the game many times, at each time you randomly
select a value for the random variable and multiply the result by its probability. After m runs of the
programs, your program must give a recommendation whether you play the game or not.
Remember if the expected value of the random variable is negative, it is a losing game; wining
otherwise.
You program should allow the user to input the values of the random variable and their associated
probability and the number of runs m. After doing the experiment, the program prints the
recommendation.
please help i cant do it!!!!!

Re: mini game in java

Richard MacCutchan3-Jan-16 22:04

How to fix the intervals on y-axis using java.

3-Jan-16 22:04

Member 11384820 wrote:
please help i cant do it!

Can't do what? If you mean you can't do anything then I suggest you go to The Java Tutorials[^] and work through the tutorials. If you mean something specific (see How to ask a question[^]) then please provide the details.

Member 1223574229-Dec-15 22:21

Member 12235742

29-Dec-15 22:21

We have a time values in CSV sheet, needs to generate a Graph for time values on X-axis and have to set a proper scale on Y-axis,
Graph should be in xlsx format, so we are converting csv to xlsx,but because of string or time/date data type it is unable to convert
complete data to xlsx which leads graph is not generating and also we are unable to fix a intervals on Y-axis.

Environment Using : Eclipse

Re: How to fix the intervals on y-axis using java.

Richard MacCutchan29-Dec-15 22:36

Java sqlite connection error

29-Dec-15 22:36

Does this have anything to do with Java?

rafiullah_Omar28-Dec-15 21:56

28-Dec-15 21:56

Hi everyone
i created exe file of a java desktop application which use a sqlite database when i install the project an i run it i give the error of attempt to write a redinly database and sometimes access in denied error
how to fix it?

Richard MacCutchan28-Dec-15 22:17

28-Dec-15 22:17

Member 11110116 wrote:
how to fix it?

With that level of detail it is anyone's guess. Please show the failing code and provide exact details of any error messages.

rafiullah_Omar29-Dec-15 18:19

29-Dec-15 18:19

i just want to insert some data there is no more and difficult code

connectivity code:

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
import javax.swing.JOptionPane;
public class Sqliteconn {
    public static Statement sqliteStmt()
    {
        try{
            Class.forName("org.sqlite.JDBC");
            Connection conn = DriverManager.getConnection("jdbc:sqlite:B12MSqlite.sqlite");
            Statement  stmt=conn.createStatement();   
            return stmt;
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, e);
            return null;
        }
    }
    
}

and insert Button Code:

String query="Insert into Employee values('"+txtID.getText()+"','"+txtName.getText()+"','"+txtFName.getText()+"','"+txtEmail.getText()+"')";
try{
    Sqliteconn.sqliteStmt().execute(query);
}
catch(Exception e)
{
   JOptionPane.showMessageDialog(null, e);
}

Erorr messages
java.sql.sqlexception attempt to write a readonly database

Richard MacCutchan29-Dec-15 22:19

29-Dec-15 22:19

A couple of things first in the following code:

Java

String query="Insert into Employee values('"+txtID.getText()+"','"+txtName.getText()+"','"+txtFName.getText()+"','"+txtEmail.getText()+"')";
try{
    Sqliteconn.sqliteStmt().execute(query);
}

Do not use string concatenation in this way to create SQL statements, it leaves your code vulnerable to SQL injection, and the corruption or destruction of your database. Use properly constructed parameterised statements.
Also you should split the execute statement into two parts for easier debugging.

As to your error, you need to establish why the database is not writable by your program. Do you have permission to write in the folder where the database is stored?

rafiullah_Omar29-Dec-15 22:56

29-Dec-15 22:56

thanks for your reply
my database is stored in same folder with project and how to allow the permission of writing?

Richard MacCutchan29-Dec-15 23:16

29-Dec-15 23:16

Check permissions and access rights of the folder and the database and see why your application cannot write to the file.

rah_sin28-Dec-15 22:21

rah_sin

28-Dec-15 22:21

It can be folder read & write permission issue where you are trying to install application

rahul

rafiullah_Omar29-Dec-15 18:08

29-Dec-15 18:08

Then how to fix it

jschell30-Dec-15 7:10

jschell

30-Dec-15 7:10

Obviously when it is a "folder read & write permission issue" then you fix it by fixing that issue.

And that is not a java issue.

rafiullah_Omar31-Dec-15 7:32