package com.martinklinke.eclipse.jfreechart.demo.views;
 
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.part.ViewPart;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.MeterPlot;
import org.jfree.data.general.DefaultValueDataset;
import org.jfree.experimental.chart.swt.ChartComposite;
 
/**
* @author martin
*
*/
public class MeterChartView extends ViewPart {
   public static final String ID = "com.martinklinke.eclipse.jfreechart.demo.views.MeterChartView";
 
   public void createPartControl(Composite parent) {
      JFreeChart chart = createChart();
      final ChartComposite frame = new ChartComposite(parent, SWT.NONE, chart, true);
   }
 
   public void setFocus() {
   }
 
   /**
    * Creates the Chart based on a dataset
    */
   private JFreeChart createChart() {
      DefaultValueDataset data = new DefaultValueDataset(20.0);
      MeterPlot plot = new MeterPlot(data);
      JFreeChart chart = new JFreeChart("Meter Chart",
      JFreeChart.DEFAULT_TITLE_FONT, plot, false);
      plot.setNoDataMessage("No data available");
      return chart;
   }
}

The result should look like the following screenshot:

JFreeChart Speedometer in Eclipse View

Of course, the MeterPlot can be further customized by calling the plot.setXXX(…) methods. However, this exercise is left to the willing reader ;)

The core of this tool is the editor for the textual UML representation that provides many features that developers are used to (syntax highlighting, validation, outline view etc.). Additionally, Graphviz can be integrated to create diagrams from the textual models.

There are detailed instructions for the installation of TextUML and the Graphviz integration and a tutorial to get started with textual modeling.

A huge advantage of textual over graphical notations is in my opinion the possibility to create diffs which means you can easily put those textual models under version control and profit from Eclipse’s compare mechanism. This enables teams of developers to share a common model and to edit it concurrently like any other piece of source code.

According to Rafael Chaves’ (the author of the project) comment on the previously linked article,

[...] the final goal is at some point to submit a proposal to Eclipse.org [...]

I hope that this goal will be reached, because TextUML is a very interesting and promising project. Claiming

• increased modeling productivity
• live graphical visualization of your class diagrams

as two of the key benefits of using TextUML, the goal should not be too far away. Productivity is always welcome and the graphical visualization may be one of the key arguments for your manager ;)

Seriously, even if it’s not the core feature of TextUML, a simple and efficient way to create class diagrams quickly would be a great win for any technical documentation or idea sketching as well.

The <workspace>/.metadata/.log file contained the following error message many times:

!ENTRY org.eclipse.jst.server.core 4 0 2008-07-11 16:24:46.251
!MESSAGE Error calling delegate RuntimeClasspathProviderWrapper[org.eclipse.jst.server.generic.runtimeTarget]: null

So this must have been a bug in resolving the server classpath. I couldn’t find an equivalent problem description, and after playing around with the project settings, adding and removing the library manually, which didn’t help any further, I tried updating the Java Standard Tools. There was indeed a patch available. My previous version of JST was org.eclipse.jst_2.0.2.v200802150100-7B-7_8dDTOvmuz0di_U5vgUfz0em and I installed the patch org.eclipse.jst.web_core.feature.patch_2.0.2.v200803241913-208i8s733I395D6BA7. My Eclipse SDK version used is 3.3.2, Build id M20080221-1800.

After the installation of the patch and a restart of Eclipse, the JBoss v4.2 entry showed up again and the error message didn’t occur any longer in the log file. As I said, I don’t really know what had happened, but the patch might have resolved the issue for me, so maybe this helps someone out there, who runs into the same problem.

In many cases, Ant is the tool of choice for automating the build process. As far as I know, Netbeans already uses Ant as build tool by default. Eclipse has its own way of describing the project configuration (source/binary folders, required libraries etc.) with files like “.project” and “.classpath”. The naive approach for building an Eclipse project with Ant would be to duplicate all the information and write a separate Ant build file that does all the work and is independent of an Eclipse instance. There are several disadvantages that come along with this approach:

1. Inconsistencies may occur whenever a new library is added or the structure of the project changes in a significant way (e.g. a new source folder is introduced) => the build file has to be updated manually when the build fails.
2. There is no real guarantee that both the Eclipse and the Ant build produce the same output => Problems may not be visible until runtime tests are performed.

So what could be a more elegant solution? Of course, to use the information for the build that is contained in the Eclipse project artifacts already. The only tool I found up to now that does right this is ant4eclipse. Basically, it defines some Ant tasks that enable the following actions (from ant4eclipse’s website):

• Setup classpathes as defined in Eclipse’s .classpath-file
• checkout complete workspaces as it’s possible with the Team Project Set feature of eclipse
• run your Java applications as you have defined them in an Eclipse Launch Configuration

This avoids the redundancy and leverages the information that is already present as soon as the project compiles in Eclipse. To be honest, I haven’t evaluated ant4eclipse yet, but I probably will as soon as the next Continuous Integration project will start. Seriously, who would like to write dozens of Ant files to do the work that Eclipse already does?

Another interesting project that seems to focus solely on Eclipse plugins, features and RCP apps is Pluginbuilder. The tutorial movie looks really impressive. The homepage says that Pluginbuilder consists of two parts:

An Eclipse plug-in allows to configure the build in the project’s workspace and run the build locally

Then the configuration can be uploaded to the server platform where the build can be scheduled

That’s a nice alternative to the manual configuration of the Eclipse headless build and integration with e.g. CruiseControl. Haven’t evaluated that one neither, but this is definitely a very interesting and promising tool for Eclipse plugin and RCP development which I can imagine may be indispensable once you are used to it.

Which other tools for Eclipse build automation do you know?

When you’re in Eclipse (IDE), press Ctrl+3, then enter the name of a view, editor, preference, command, menu etc. or previously opened resource (e.g. a Java class), select the desired match from the list and voilà – Eclipse navigates you there. You can also enter the initials of the words you are looking for, e.g. “pe” for “Package Explorer”. That’s really a cool feature and available since Eclipse 3.3. It brings kind of a “spotlight feeling” to your development work ;)

Good bye, “Show View” and “Open Perspective” ;)

The solution is to enable structure detection for the Subversion repository:

• Switch to the SVN Repository Exploring perspective in Eclipse
• In the SVN Repositories view, right-click on the repository and select Location Properties…
• Go to the Advanced tab and activate Enable Structure Detection

Of course, the Resource Names must correspond to the folders in the repository to make this work.

From now on, the tag dialog will ask you for the Tag instead of the full Location.

Migration in a nutshell:

1. DO NOT UNINSTALL the Polarion.org version before installing the Eclipse.org version, otherwise you may lose all your SVN settings.
2. Install the new version of Subversive + the SVN connectors (still from the Polarion site).
3. Migrate your workspace via Help > Subversive > Migrate Projects and Settings. Do this for EACH workspace you want to be up-to-date.

(Please refer to the above mentioned migration guide for details.)

Unfortunately, shortly after I started the migration of projects and settings in my workspace, the dialog did not show any further progress after reporting that settings were converted and Eclipse seemed to hang somehow. Since nothing happened after a while, I decided to terminate the process and restart Eclipse. This time the migration worked, except for a warning that some closed projects could not be remapped. So I opened those projects and performed another migration which finished without any errors.

The next weeks will show whether it was a good idea to migrate to the still incubating project ;)

“The Riena platform will be the foundation for building multi-tier enterprise client/server applications. As such Riena will broaden the usage of the service oriented architecture of OSGi/Equinox by providing access to local and remote services in a transparent way. Using this uniform programming model, the components of Riena and the business components of the enterprise application can be developed regardless of their target location. Components are later easily placed on client or server depending on the business requirements.”

The ideas behind Riena look very promising. If you have previously faced the task of writing a RCP client for an enterprise application, e.g. based on EJBs, then you have probably already struggled with at least some of the items on the project plan. Instead of putting all your effort into the features and usability of the application, you end up spending a considerable amount of time debugging RMI classloading issues (until you place Thread.currentThread().setContextClassLoader(this.getClass().getClassLoader() in your bundle’s start method or before any remote access in some ServiceLocator…) or configuring authentication/authorization mechanisms. Not to mention the tedious exception handling of pre-EJB3 session beans… Of course, you can solve such problems somehow on your own, but you should always ask yourself why you have to solve them and why there is no built-in framework or component that handles the intricacies for you.

I’m also very curious about the announced persistence support. I wonder if service tiers for data access will be addressed. You have to decide at some point to either provide dedicated data transfer objects or the mapped entities themselves. However, the latter brings up further questions regarding lazy loading of uninitialized fields of objects that have already been transfered to the client. But more on this possibly in another post…

Hopefully, with Riena, we can soon spend less effort on infrastructure and concentrate more on things that matter.

• Rating of software architectures, Part 1: Method
  Dr. Gernot Starke – very good speaker
  Experience is required for rating architectures; functional requirements are not enough; Quality tree -> ISO…, ATAM (Architecture Tradeoff Analysis Method (SEI))
• SOA – Defining services from a business point of view
  Lars Roewekamp, OpenKnowledge GmbH – ok, slides hardly readable from the back (small fonts)
  Some interesting thoughts about structuring services and service operations according to business requirements rather than existing IT architectures.
• Keynote: Bringing Web 2.0 in the Enterprise
  Rahul Patel (Oracle)
• Persistence with Spring
  Eberhard Wolff, Interface21 Germany – very good speaker
  Comparison of different persistence approaches using spring templates for plain JDBC, iBatis and O/R-mappers like Hibernate; recommendation to use O/R-mappers with great care, especially if database-centric/relational concepts have to be considered (batch operations, stored procedures etc.).
• Keynote: The security development lifecycle at Microsoft
  Sebastian Weber, Microsoft Deutschland GmbH
  www.thedailywtf.com ;)
• Message-oriented architectures based on Spring
  Jürgen Höller, Interface21 – good speaker
  API-oriented approach outlining the differences between messaging and asynchronous execution; would have expected to see some example architectures, but there were “only” small source code examples; nevertheless an interesting topic
• Eclipse Code Camp Night
  Moderated by Wayne Beaton, Eclipse Foundation
  Some specific eclipse development problems were discussed ad-hoc; had some discussion with Wayne and Bernd Kolb about security in enterprise application clients based on RCP, but came to the conclusion that there is no project/proposal yet, unless I wrote one ;)