Questions tagged as 'java'

Tagged questions
2
answers

Java Programming (Basic POO: Exception in thread "main" java.lang.NullPointerException)

I copy and paste (it seems to me more comfortable than an image) the code. package nueve; import java.util.Scanner; public class nueve { Scanner sc = new Scanner (System.in); private int arreglo; private int AñoEdad=2017; priv...
asked by 31.05.2017 / 01:12
1
answer

How to properly create objects in Java dynamically?

I need to create quantity of components n what I do not know, if it is properly written the way I do it public class cualquierClase{ private JTextArea textAreaTab; private JTextArea createTextAreaTab(int row, int col, String nameTextArea){...
asked by 15.05.2017 / 21:35
1
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Problem when displaying the contents of an array in a file

The problem I have is that I need to save the temperatures of a week in a file and when I do, the file only shows me the last temperature entered. I do not know where the error is so that it shows me all the temperatures. public class Princ...
asked by 26.04.2017 / 10:44
2
answers

Format style of documentation comments in Intellij Idea using keyboard shortcuts

Approach First of all we do not find in JavaDoc , in Java. I have the following text that I want to insert as part of the JavDoc: Esto es el commentario de JavaDoc que quiero exponer en la pagina de stackverflow y que despues voy a d...
asked by 24.04.2017 / 07:47
1
answer

"Can not format given Object as a Number" when displaying JTable

Greetings, I have a problem when showing the contents of a database in a JTable table, in a .java project using netbeans. I tried to observe the output of the column with which I get an error, it is the 5th column a data of type Float, the 4t...
asked by 22.04.2017 / 23:29
1
answer

Use swing timer correctly to hide Jlabel

I need to hide a Jlabel with Swing Timer after 5 seconds, the problem is mainly that once the Timer starts, this apparently is not stopping at any time, since when using the Show button for the second time, the Jlabel disappears almost instantan...
asked by 11.05.2017 / 15:37
3
answers

Problem when inserting data in android studio database

The problem I have is that if I try to insert an empty data the application fails and I do not know why. With any number goes well but if I leave it empty it fails I have the database: public class AdminSQLiteOpenHelper extends SQLiteOpenH...
asked by 08.04.2017 / 22:30
1
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Plugin eclipse subversive generates error and eclipse does not start

I have installed the latest version of eclipse (Oxygen) and I have problems installing the subversive plugin from the marketplace. After installing this, I get an error and if I close eclipse, then it does not start. I have tried to delete...
asked by 20.07.2017 / 12:07
1
answer

Difference between @WebServlet ("/") and @WebServlet ("/ *")

When creating a servlet , what is the difference between using the following patterns to define the URL? "/" and "/*" , using annotations and the specification 3.1. @WebServlet("/") @WebServlet("/*") Which of these URL...
asked by 23.07.2017 / 16:56
1
answer

create table from java that has a database in access

I would like a table, when I want it to increase again from 1, but I searched in many places and this can not be done from java ... although if someone knows it would be great, if they could help me. Then going back to the topic, as an alternati...
asked by 11.03.2017 / 05:04