29 April, 2010 - 10:29 am
Tags: Class, Java, method, programming, Reflection
Posted in english | 1 comment
import java.lang.reflect.*; public class Foo { public void bar(int param){ System.out.println(param); } public static void main(String args[]){ Object f = new Foo(); try { Method m = f.getClass().getMethod("bar", int.class); m.invoke(f, 42); } catch (Exception e){ System.err.println(e); } } } $ java Foo 42
8 April, 2010 - 1:09 pm
Tags: getruntime, Java, programming, runtime
Posted in english | No comments
I don’t like the approach of calling native shell commands in any language instead of using multi platform libraries, but here is a little prof of concept Java program to call native commands. import java.io.*; import java.util.*; public class Exec { public static void main(String args[]) throws IOException { Process proc = Runtime.getRuntime().e xec(args); BufferedReader [...]
Iterating over a HashMap using the enhanced loop (foreach) in Java is a good way to keep your code smaller, more legible and usually more semantically coherent. import java.util.HashMap; import java.util.Map; class Foo {} public class Main { public static void main(String args[]){ Map<Byte, Foo> mHash; mHash = new HashMap<Byte, Foo>(); [...]
This is a simple program I wrote called Who Am I that shows informations about the device which it is running. Which can be useful for developers and maybe advanced users. Download: WhoAmI.tar.bz2 – Eclipse project. It’s configured for Android platform 4 (1.6) but should work without problems in newer Android platform versions. WhoAmI.apk – [...]
27 February, 2010 - 9:39 pm
Tags: caps lock, Java, programming, socket, upcase
Posted in english | 1 comment
Here is a simple server for those who are starting studying sockets or just needs a simple socket server example for reuse while writing your own behavior. Features: A client should enter a string and the server would answer the same string, with each symbol in up case, when possible. Default port at 8080. One [...]
22 February, 2010 - 5:16 pm
Tags: development, i18n, Java, JUnit, locale, programming, String, teste unitário, toString, unit testing
Posted in english | No comments
Today I was programming a toString method for a class widely used in a application, using the very useful String.format that provides a C’s like printf formatter. @Override public String toString() { return String.format("VO[a: %.1f, b: %.1f, c: %.1f]", a, b, a+b); } %.1f means a float with one digit precision after the dot separator. [...]
5 January, 2010 - 6:10 pm
Tags: AWT, fonts, Java, JVM, Larabie, Larabie Fonts, programming
Posted in english | Comments Off
Here’s a program that lists fonts available in your JVM. You can also set the environment variable JAVA_FONTS to specify the font directory. import java.awt.GraphicsEnvironment; public class ListFonts { public static void main(String args[]){ GraphicsEnvironment e = GraphicsEnvironment.getLocalGraphicsEnvironment(); for(String font:e.getAvailableFontFamilyNames()){ System.out.println(font); } } } By using pipes you can count how many fonts you [...]
19 December, 2009 - 7:15 am
Tags: C, Java, Python, Qt, Tiled
Posted in english | 4 comments
I’m using the Tiled Map Editor for a while, I even wrote that tutorial about it. It’s a general purpose tile map editor, written in Java but now migrating to C++ with Qt, that can be easily used with my set of free pixelart tiles. A map done with Tiled is stored in a file [...]
This is a very simple example of how to open two images and display them added. I got two pictures at project Commons from Wikimedia that were highlighted on Featured Pictures. I did a crop on both to have the same size, as I’m trying to make this example as simple as possible. The first [...]
Here’s a simple video player that also performs facial detection thought the Open Computer Vision Library. Here’s a code developed using codes from nashruddin.com and samples from OpenCV, including the haar classifier xml. More detailed explanation on the theory about how the OpenCV face detection algorithm works can be found here. The code: #include <highgui.h> [...]
14 August, 2008 - 11:42 am
Grande Silveira!
Curti o visual novo do Blog, mais limpo que o antigo.
E que venha o NetBeans 6.5! Estou aguardando ansiosamente :)
Aquele abraço