JavaFX Eclipse plugin error

If you decided to give it a try to JavaFX using Eclipse you may run into your first problem right after installing the JavaFX plugin for Eclipse and it may look like these errors:

Cannot access java.lang.Object class file for java.lang.Object not found
Invalid assignment
Package javafx.scene does not exist
Package javafx.stage does not exist

First of all make sure that you added correctly the JavaFX SDK to your libraries:

If this is correct then take a look at your ".classpath" file and make sure that the JavaFX entry looks like this:

      <classpathentry kind="con" path="com.sun.javafx.eclipse.core.classpath.SDKClasspathContainer"/>  

And not like this:

      <classpathentry kind="con" path="com.sun.javafx.eclipse.core.classpath.SDKClasspathContainer/reserved/desktop"/>  

That fixed it for me ;)

Eclipse button problem with Kubuntu 9.10 (Karmic Koala)

I ran into this issue while installing the Google App Engine... a quick description of the problem is that some buttons in Eclipse were not responding (doing nothing) after I upgraded to Karmic Koala, after checking the log file, network connection settings and some other things that didn't work I decided to ask the oracle (Google) about it and after a while I found a simple and quick solution here.

Just create an executable file with the following content:

 #!/bin/sh  
 export GDK_NATIVE_WINDOWS=1  
 /opt/eclipse-3.5/eclipse  

Now back to coding ;)

Eclipse Galielo and Google App Engine Plugin

I just installed Galileo and I went straight to the update site to install Google App Engine plugin but for some reason after adding the site (http://dl.google.com/eclipse/plugin/3.5) and following the instructions, Galileo simply didn't do ANYTHING after I clicked on the "Next" button, anyway I found the zip files here and it is just as simple as any other plugin.




1. Download the zip file here for you version.
2. Unzip it at the "dropins" folder in your Eclipse (Galileo) directory.
3. Restart Eclipse

That's it ;)

JavaFX @JavaOne 2009

Now that the JavaOne opening presentation is over my guess is that most JavaFX developers are thrilled with all the news presented in just a couple of hours and jumped back on their keyboards trying to code the newest coolest application out there, on my side I decided to post a summary of the news that interested me the most:

• Oracle CEO Larry Ellison giving his support to JavaFX and talking about Oracle's interested in this technology.
• JavaFX SDK 1.2 available on Linux even though is a beta version it is still good news.
• An enhanced version of the plugin for Eclipse is available for those that are not so keen to use Netbeans that much. You can read more information about the release on Neil Bartlett's blog entry here.
• Finnally a reasonable good UI tool is available, take a look at JFXBuilder here, it is still in the early stages but it offers a few cool things.
• Verizon revealing that will open an application store based on Java ME and also making available APIs for developers to write rich applications.

Well it has been a very good day for Java developers, and let's hope that all (or at least most) of the doubts about the future of JavaFX is clear after these annoucements, I guess the time will tell.

A few simple but useful Eclipse tips

Eclipse is the most popular Java IDE in use by developers, and there are many of them spending hours and hours in front of it everyday trying to solve issues, create new functionalities and such, here goes a couple of simple but very useful tips to make those hours more productive:

• Use "Ctrl + Page Up / Down" to walk between opened editor tabs.
• Try "Alt + Left / Right" to go backwards and forwards in your editing history.
• Finnally use "Ctrl + F6" to cycle through opened files.

Hope this helps ;)

Pimping Eclipse Ganymede

Today I decided to try the new Eclipse Ganymede (3.4), but honestly after setting up Eclipse with all the plugins that I am used to have at hand right away, upgrading it to a new version doesn't seem so appealing to me, on the other hand, I'm open to new functionalities and enhancements and I was curious about javaFX (it requires the new Eclipse) and its possibilities to use the same code for a RIA in a browser, mobile or desktop, so this was enough for me.

As usual downloading and installing Eclipse couldn't be easier, so after doing it I started thinking about my favorite plugins and noticed how it is always a problem for me to remember them , so it seemed useful to create this list and share it with the world.

• Eclemma: is a Java code coverage tool for Eclipse that allows the user to adopt EMMA's philosophy in an easier and more graphical way.

  • Update site: http://update.eclemma.org/

• Jar Class finder: allows the user to find Java classes and solve NoClassDefFound exceptions, specially useful while searching for a class inside a group of jars.

  • Download site: http://www.alphaworks.ibm.com/tech/jarclassfinder/download

• DBviewer: this plugin lets you view the database structure (schema/tables/column), execute queries and includes content assistant, among other features.

  • Download site: http://sourceforge.jp/projects/dbviewer/releases/

• Subclipse: an open source plugin to provide support for Subversion inside Eclipse. A great asset for Linux users since there is no equivalent to Tortoise yet.

  • Update site: http://subclipse.tigris.org/update_1.6.x

• m2eclipse: is the Maven integration for Eclipse, takes care of the dependency management and automatic download, plus launching Maven builds.

  • Update site: http://m2eclipse.sonatype.org/update/

• Origo Mylin connector: if you are working on a task-focused project using Mylin, this connector will let you use Origo as the open/closed source hosting site.

  • Update site: http://download.origo.ethz.ch/mylyn/update-site-2.0.0/

Maven and the Java Heap size...

Have you ever ran into this error while compiling a project using Maven in Eclipse:

"Java heap space error"

Well this can be easily solved by adding a couple of parameters to the JRE being used in Eclipse. Go to the following location:

Window/Preferences/Java/Installed JREs

Edit the JRE that is ticked and in the Default VM arguments add this:

-Xms128M -Xmx256M

You can modify these values according to your needs, and in case you had this problem while compiling through the console try setting this variable:

export MAVEN_OPTS="-xMS128m -xMX256m"