Two Useful Eclipse Plugins

FindBugs uses static analysis to look for bugs in Java code.

ANTLR IDE provides support for ANTLR parser generator.

Subversive Problem

I am using Subversive - the Eclipse subversion plugin - 0.7.7 plus its subversion connector 2.1.0.

Today an exception jumped out of nowhere, making all my subversion based projects unable to synchronise with the server.

java.lang.NoSuchMethodError: org.eclipse.team.svn.core.connector.SVNChangeStatus.(Ljava/lang/String;Ljava/lang/String;IJJJLjava/lang/String;IIIIZZLjava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;JZLjava/lang/String;Ljava/lang/String;Ljava/lang/String;JLorg/eclipse/team/svn/core/connector/SVNLock;JJILjava/lang/String;ZZLorg/eclipse/team/svn/core/connector/SVNConflictDescriptor;)V
at org.tigris.subversion.javahl.ConversionUtility.convert(ConversionUtility.java:287)
at org.tigris.subversion.javahl.ConversionUtility$4.doStatus(ConversionUtility.java:146)
at org.tigris.subversion.javahl.SVNClient.status(Native Method)
at org.polarion.team.svn.connector.javahl.JavaHLConnector.status(JavaHLConnector.java:406)
at org.eclipse.team.svn.core.extension.factory.ThreadNameModifier.status(ThreadNameModifier.java:606)
at org.eclipse.team.svn.core.utility.SVNUtility.status(SVNUtility.java:330)
at org.eclipse.team.svn.core.utility.SVNUtility.getSVNInfoForNotConnected(SVNUtility.java:803)
at org.eclipse.team.svn.core.SVNTeamProvider.uploadRepositoryResource(SVNTeamProvider.java:241)
at org.eclipse.team.svn.core.SVNTeamProvider.connectToProject(SVNTeamProvider.java:172)
at org.eclipse.team.svn.core.SVNTeamProvider.getRepositoryResource(SVNTeamProvider.java:71)
at org.eclipse.team.svn.core.svnstorage.SVNRemoteStorage.loadLocalResourcesSubTreeSVNImpl(SVNRemoteStorage.java:628)
at org.eclipse.team.svn.core.svnstorage.SVNRemoteStorage.loadLocalResourcesSubTree(SVNRemoteStorage.java:521)
at org.eclipse.team.svn.core.svnstorage.SVNRemoteStorage.getRegisteredChildren(SVNRemoteStorage.java:273)
at org.eclipse.team.svn.core.synchronize.AbstractSVNSubscriber.resourcesStateChangedImpl(AbstractSVNSubscriber.java:212)
at org.eclipse.team.svn.core.synchronize.AbstractSVNSubscriber.resourcesStateChanged(AbstractSVNSubscriber.java:169)
at org.eclipse.team.svn.core.svnstorage.SVNRemoteStorage$3.runImpl(SVNRemoteStorage.java:152)
at org.eclipse.team.svn.core.operation.AbstractActionOperation.run(AbstractActionOperation.java:77)
at org.eclipse.team.svn.core.operation.LoggedOperation.run(LoggedOperation.java:38)
at org.eclipse.team.svn.core.utility.ProgressMonitorUtility.doTask(ProgressMonitorUtility.java:104)
at org.eclipse.team.svn.core.utility.ProgressMonitorUtility.doTaskExternal(ProgressMonitorUtility.java:90)
at org.eclipse.team.svn.core.utility.ProgressMonitorUtility$1$1.run(ProgressMonitorUtility.java:60)
at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:1800)
at org.eclipse.team.svn.core.utility.ProgressMonitorUtility$1.run(ProgressMonitorUtility.java:58)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)

The only possible reason that I can think of is I accidentally copied some ".svn" directories into some non-subversion-based project.

On eclipse.technology.subversive Newsgroup, there is a discussion on the same exception, but happen on Subversive 0.7.8.

I am very lucky since after I changed the subversion connector in use from Native JavaHL to SVN Kit, the problem seems gone! Otherwise, all my development work has to stop!

Add to Version Control before Commit

I am using Eclipse 3.4.2 Ganymede plus Subversive 0.7.7. If I try to commit some newly added files, i.e., they are not under subversion control yet, Eclipse simply becomes irresponsive.

New files MUST be added into version control first, before they can be committed.

Use Eclipse RAP to Build Rich Internet Application

It is a pity that I had not heard of Eclipse RAP (Rich Ajax Platform) when last year I developed Grimoires Browser, an Eclipse RCP based client for the Grimoires Service Registry.

RAP has joined the family of Eclipse UI toolkits, as existing ones such as SWT for Windows, SWT for Liunx, and SWT for Mac. In some sense, RAP can be considered as SWT for Web.

RAP is ued to develop Rich Internet Application (RIA). To develop an RAP-based web application, programmers are still working in Java, in SWT, and in JFace. And RAP makes sure the UI is built on top of HTML, JavaScript and Ajax. Remind you something? Yes, GWT. There are some very good introductory articles [1, 2] about RAP on IBM Developer Works.

It is claimed that in a minimal effort, we can transform an existing RCP application to RAP; or we can even build an application which is largely independent of RAP or RCP. So it can run as both a web application and a desktop application.

No doubt, RAP is the way to go to make Grimoires Browser a web application. It will then totally relieve users the pain to install some software on their machine in order to access Grimoires.

My Safe

My Safe is an Eclipse RCP based software I developed last year. As suggested by its name, it is a secure file manager.

It is easy to use. You must input the correct password in order to enter My Safe. Inside My Safe, you can see all directories and files as they originally are. But these directories and files are encrypted in the file system. And they are decrypted on demand in My Safe's interface. The password you use to enter My Safe is the key for encryption and decryption. AES is used as the cipher.

I want to argue that such software as My Safe is necessary even on our personal desktops or laptops. So that other people may possess our computer but can not possess our data.

My Sony laptop does have a secure drive called My Safe as well, but it is not perfect. It is a proprietary technology. It means the data is tightly bound to the Sony laptop. So if the software is broken, there is no way for me to recover the encrypted data. And I can not decrypted the encrypted data on another computer.

Therefore I developed my very own My Safe. And it turns out to be very useful!

WTP Europa Release

Eclipse Europa is the annual release of Eclipse projects of 2007. Here are some of my experience about it. Since I am using WTP mostly, my experience is mainly concerned with WTP.

Interesting, my WTP 2.0 can not start up with -Xmx1024m. But it is able to start up with a smaller maximum heap size, for instance, -Xmx768m. While my other Java application, such as Tomcat, has no problem with -Xmx1024m. I am using JDK 1.6.0_01. I posted a message at the eclipse.webtools newsgroup. I will follow this issue.

It is desirable that WS explorer has an extension point to support application domain service description document (non WSDL). WS explorer can be used as a UDDI browser. In UDDI data model, the service entity can be associated with a tModel, which is simply a link to some non-registered document that further describes the service, for instance, the WSDL of the service. WS explorer supports to retrieve the WSDL, visually display it, and even invoke its operations.

I am working on the Grimoires project, which is an extended UDDI service registry supporting metadata annotation and service discovery by interface signature. In our practice, we very often see that users design their own service description language, instead of WSDL, to describe their services. For instance, the myGrid project, an influential service-oriented bioinformatics experiment environment, uses its own Feta schema. GLUE is a popular schema to describe services and resources in grid computing.

explorer has an extension point to support application domain service description document (non- explorer to open it; if it points to some non-This is understandable. First, it is cheap to design an XML schema for their XML-based service description language. Second, it improves usability with a DSL (domain specific language) in place. According to UDDI' data model, the URL of domain specific service description documents can be put into a tModel, then associated with the service entity. Thus it is desirable that WSWSDL). That is, if the tModel points to WSDL, then WS explorer uses its embedded WSDLWSDL document, the WS explorer uses some extension registered corresponding explorer to visually handle it. Somehow UDDI's tModel can be considered as an extension point of UDDI data model, because it allows any document with a URL to be associated with a service.

The benefit of such an extension point in WS explorer is to improve usability by supporting domain-specific service description documents, which further enhances the expressiveness of service description: whether the description document is WSDL or non-WSDL, standard based or domain specific, current supported or emerging, all can be handled by WS explorer.

Another desirable feature is about being able to print visualized XSD/WSDL supports visualizing . WTPXSD/WSDL. The visualized result is very informative and is a good source to be put into documentation. But this is not supported a couple of years ago. It is very good that now WTP 2.0 supports printing visualized XSD! (Although I am not sure exactly since which version WTP has implemented this.) But the printed visualized XSD loses its icons standing for XSD attribute and element. And it still does not allow to print visualized WSDL. I am not sure whether there is some technical difficulty for printing contents of arbitrary editors.

Web Services Explorer in Eclipse

Web services explorer in eclipse can be used to browse UDDI registries, to parse services' WSDLs, and even to invoke service operations by sending them SOAP messages. It is implemented as a web application running on eclipse' embeded application server. So I am thinking to turn it into a standalone web application to act as Grimoires' web-based interface. As Chris Brealey pointed out, the WTP team also has this idea, but it is not easy to do this and the WTP team simply has no resource to be allocated on this. I played web services explorer today. It relies on quite a lot eclipse plug-ins. Even it could be turned into a standalone web application, it would be of a large footprint.