Today I’m traveling to Zürich to join Jazoon to talk JavaFX game development. Before the event I’ll try to visit Bern and after the event I’m going to Lison, so Brussels and then Amsterdam. That’s the plan!

During the next days I’ll try blog from there. Bye.

\o/

There’s also a lots of improvements in the language and the API. For details on that read this document. Unfortunately, as a side effect of those great changes some JavaFX source codes posted here are now deprecated and need a few changes to compile again but the online preview of them as applet or Java Web Start will continue to work well.

Let’s code.

Footprint is a publisher and distributor of certificates of participation in conferences – signed PDF documents that prove you attended a conference or a course.

This is a little JavaFX application that shows how to create a interface that displays data provided by services. This version uses three services: one that counts the number of users, other that counts the number of events and one that list these events. Check out the source code here.  Try the application as a draggable JavaFX applet here.

Usuually on JavaFX we grab data using HttpRequest from external resources on formats like JSON or XML. I showed how to get it on the post Reading Twitter with JavaFX and how to parse it using PullParser on the post Parsing a XML sandwich with JavaFX.

Another day I need to grab and interpret some plain results, not in XML nor JSON, while consuming a REST service. In this case we don’t have a well structure data so the PullParser won’t help us.

Example 1: Reading Raw Data

In this example we’ll load a plain text file served in a remote location.

var planetsRequest = HttpRequest {
    location: "http://silveiraneto.net/downloads/planets";
    onInput: function(stream: InputStream) {
        var buff = new BufferedReader(new InputStreamReader(stream));
        var line = "";
        while((line = buff.readLine())!=null){
            println(line);
        }
    }
}
planetsRequest.enqueue();

This will produce the output:

Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune

Example 2: Discovering your IP Address

In this example we’ll examine how to integrate a request of a remote data in a running graphical program.

The best way to know your real IP address is asking for a remote server to look which IP made that request. It’s like calling for a friend and asking him which number appeared in his mobile. =) This server side Python script prints the IP address of who requested the page.

#!/usr/bin/env python
import os
 
print "Content-type: text/html"
print
print os.environ['REMOTE_ADDR']

In the client side, with JavaFX, we’ll load the remote value into a local variable. The ip is assigned with the value “…” and later the ipRequest will replace it with a String with the IP. The bind feature will automatically fix the GUI String text.

For the user he will see the ellipsis for a few seconds and so their IP.

import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.text.Text;
import javafx.io.http.HttpRequest;
import java.io.*;
 
var ip = "...";
 
Stage {
    title: "What is my IP?" width: 250 height: 80
    scene: Scene {
        content: Text {
            x: 10, y: 30
            content: bind "My IP is {ip}"
        }
    }
}
 
var ipRequest = HttpRequest {
    location: "http://silveiraneto.net/scripts/myip.py";
    onInput: function(stream: InputStream) {
        var buff = new BufferedReader(new InputStreamReader(stream));
        ip = buff.readLine();
    }
}
ipRequest.enqueue();

You can try this JavaFX applet here.

Example 3: Reading Integer values

Until now we handled just plain Strings. But in some cases you want to get number as non structured data. In this case you need to know previously which type the data is. In the case of a web service this probably will be described in a WSDL file.

Here I’m writing a very simple service script at Zembly, a great platform for cloud computing. It’s called aplusb, it justs add the first parameter A to the second B.

if ((Parameters.a != null) && (Parameters.b!= 0)) {
return Parameters.a+Parameters.b;
}

The service is published at Zembly here where you can see more details on how to invoke it.

A simple way to invoke it on JavaFX and than getting the value as an Integer:

import java.io.*;
import javafx.io.http.HttpRequest;
 
var a = 100;
var b = 200;
var result = 0 on replace {
    println(result);
}
 
var zemblyRequest = HttpRequest {
    location: "http://zembly.net/things/1827f696529d4e6f940c36e8e79bea1c;exec?a={a}&b={b}";
    onInput: function(stream: InputStream) {
        var buff = new BufferedReader(new InputStreamReader(stream));
        result = Integer.valueOf(buff.readLine());
    }
}
zemblyRequest.enqueue();

The output will be:

0
300

The first 0 is from the first assignment on the var result. The 300 is from the webservice itself.

The same approach can be used to convert the ASCII/Unicode result from the stream to the suitable type on a variable.

Programação:

Download: em MP3 ou em OGG.

Participei no dia 21 de Maio do programa Rádio Debate da Universitária FM, apresentado pelo Agostinho Gósson, jornalista e professor do Departamento de Comunicação Social da UFC, sobre segurança na rede, vigilantismo na Internet, Software Livres e outras coisas mais. Foi uma satisfação imensa conhecer esta rádio que eu escuto quase todos os dias e conhecer algumas das figuras que cujas vozes habitam meu imaginário. Não preciso nem dizer que estava muito nervoso nas primeiras falas, mas depois eu fui me acostumando. É estranho falar com o Agostinho, dá impressão que eu estou na rua, dirigindo, ouvindo.

Estou dando uma olhada no Kdenlive, um editor de vídeo não-linear, livre, focado na facilidade de usar e na flexibilidade. O vídeo acima foi produzido com uma série de fotos de uma reunião do Casa Brasil, títulos feitos no Gimp e música livre do artista Antony Raijekov.

As fotos originais estão neste meu álbum no Flickr. O vídeo em mais alta resolução está em reuniao_casabrasil_maio_2009.ogg (apróx. 12Mb) ou reuniao_casabrasil_maio_2009.avi (apróx. 378Mb).

javafx4linux.tar.bz2 (~ 36Mb).

Installing

1) Extract the javafx4linux.tar.bz2 file. In this example I’m placing it on my Desktop. After the installing process you can remove it.

2) Open your NetBeans 6.5 and go at Tools → Plugins and go to Downloaded tab. In a plain and new NetBeans installation there will be no plugin in this tab yet.

3) Click on the Add Plugins button and head to the directory you extracted the file and select all .nbm files.

4) You will see a list of 22 plugins selected. Click on the Install button.

5) Just keep clicking on the Next button.

6) Check the license agreement accept box.

7) You’ll see a warning because the Linux pluggin is not signed. Don’t worry, just click Continue.

Click on Finish to restart NetBeans.

9) Now we can test it. Go at File → New Project, select the JavaFX on Categories and JavaFX Script Application on Projects.

10) Put some code and run it. There is. JavaFX on Linux.

Considerations

This is not a official of JavaFX for Linux! This solution was tested on Ubuntu 9.04 “Jaunty Jackalope” with Java 6 update 13 and NetBeans 6.5.1, but should also work with others Linux distributions and Java versions greater than 5.

Known bugs

As a non official workaround for JavaFX for Linux you may notice some drawbacks. Some parts of the JavaFX runtime rely on native implementations on the specific operational system. You may not use some multimedia capabilities as video playback, JavaFX Mobile emulator and some performance issues in some effects. Despite that, is perfectly possible to develop applications using JavaFX on NetBeans.

Thanks

I’d like to thanks some guys around the world. Weiqi Gao’s original post on JavaFX on Linux, HuaSong Liu article on DZone and Kaesar Alnijres post.