World of Bytes

Run jar files on Windows Vista

2009-05-12T10:43:00.000-05:00

If we install a program that stole the .jar association we can restore it, so when you double-click a jar file, it opens automatically. To do this, you have to download and run JarFix program. http://www.jonelo.de/java/jarfix/ After execution the association will be restored and now you can open jar files with double-click.

XNA using custom fonts

2009-03-20T09:09:00.000-06:00

When we are creating a game one of the importat part is the text that we display, but we don’t want to use the boring fonts that our system has installed. The following steps helps us to add and use a new font in our game. Download new font Install font on the system In Windows XP: Copy the font file and paste it in /Windows/Fonts Create or Load a Project Right

Blogger Tags Cloud

2009-03-20T08:46:00.001-06:00

If You want to add a Tags cloud to your Blog you can see this tutorial. http://phy3blog.googlepages.com/Beta-Blogger-Label-Cloud.html This tutorial is for Blogger and you have to add a “Labels widget” to the site

Compile a java package

2009-02-13T11:16:00.001-06:00

When we compile a java file, we use the "javac" tool javac File.java The problem is that if we have packages and we have to compile them we might do it file by file. This solution has a problem because if files have references to other class in the package we have to compile them in an specific order. In order to do this task more easy we have to go to the root directory of the project and

Deleting files with Java

2009-02-11T22:47:00.000-06:00

We Can delete files on java, in order to do so, we have to use the File class. java.io.File file = java.oi.File("String with path"); file.delete();This method return a boolean if the file was deleted.In case we have to create temporary files and to be deleted on the end of the program, we can use other method in the File class. java.io.File file = java.oi.File("String with path");

Turning off machine from Java

2009-01-23T09:40:00.000-06:00

The following code can make a java program shutdown the machine, this only works on Windows (XP and Vista) try{ Runtime rt = Runtime.getRuntime(); Process pr = rt.exec("cmd /c shutdown -s");} catch (Exception e){ JOptionPane.showMessageDialog(null, ew.toString()); ew.printStackTrace();}This will make to shutdown the computer in 10 seconds, to set the time we can change the string to:shutdown -s

Sang Shin

2008-11-03T21:30:00.002-06:00

My bag with Sang Shin autograph :D

Initialization Blocks

2008-10-15T21:38:00.003-05:00

Image we have this class:public class Student{ private java.util.List nicknames; private String name;private String lastName;private int age;}Now we have to do the Constructors of the class. We have to start with the most specific constructor, the one that have all the properties of the object. public Student(String name, String lastName, int age){ this.name = name; this.lastName =

Accesing JavaDB

2008-10-11T01:49:00.005-05:00

How to access a DataBase with JavaDB?First Step (Creating DataBase):With netbeans in Services tab, we can create the database like this:Then we assing a name, user and password:With the database created we have to create tables; Go to the database, connect and create a Table named 'FRIENDS', add a colum for 'NAME' type VARCHAR(50), then insert some data.Second Step (Create Project)Now create some

Statement labels

2008-10-07T10:45:00.004-05:00

Statement labels [JLS 14.7] are a little-known feature in java, let's see an example of how to use them.We have the following int matrix: final static int[][] matrix = { {1,2,3,7}, {6,3,9,4},{8,4,3,2},{5,8,3,4} };The purpose is to find out if the number 7 is stored in the matrix, since we aren't allowed to sort the matrix, a brute force algorithm must be usedpublic static boolean existsSeven(){

Array Copy

2008-10-06T13:26:00.004-05:00

Arrays are an important way to save data. Sometimes we have to create a copy of that array to another.We could acomplish this task with the following code: public class Copy(){int[] array = new int[55555];}public int[] copyArray(){int[] arrayCopy = new int[array.length];for( int i = 0; i < array.length; i++ ) arrayCopy[i] = array[i];return arrayCopy;}For each position we copy the value from one

OSUM?

2008-10-02T23:01:00.003-05:00

OSUM - Open Source University Meetuphttp://osum.sun.com/This website is a social network where we can share comments, photos, videos and blog posts about Java technology, subscribe to it and enter in your university group.Invite others to make this community grow!

JIT

2008-09-21T19:58:00.008-05:00

Java has been targeted as a "slow" programming language but since JDK 1.3 the HotSpot Technology was included, the HotSpot JVM was born. One important part of the JVM is the Compiler, and I'm not refering to the "javac" tool but to the HotSpot Compiler, a JIT compiler.This Just-In-Time Compiler translates the java bytecode into native code. The compilation doesn't happen at class-level but at

Hello World Classes

2008-09-19T12:28:00.004-05:00

All Programas writted in Java need to be defined in a Class, this class depend on other classes and those depend on others as well, so when we run an application the JVM needs to load those classes to run the program.So how can we know the classes that the JVM loads?The answer is simple: We have to use the -verbose:class option of the JVM.The traditional exercise to start learning a programming

Performance

2008-09-18T09:53:00.012-05:00

Java is one of the most used programming languages in the world or at least one of the most famous. One of its weakness is the speed of execution and ram footprint.I'll show some of the features that java provide to improve the perfomance, by customize the JVM or by writting better code.The first step that we are going to see for perfomance is the time of execution.In order to do this, we will

First Post

2008-09-17T18:14:00.002-05:00

Hey!Here I'll be writting some stuff about Java.Stay tuned.