Salient Soft

If you want to configure the libraries for use with a particular Eclipse plugin, this can seem rather a mystery at first. The traditional way in Eclipse to configure libraries for a project is to open the project properties for a project, select Java Build Path in the list on the left, and visit the libraries tab in the pane on the right. You can then use the “Add Jars” or “Add External Jars” to add jars to the project. To improve project portability across different development platforms, you can also add Classpath Variables which can be defined appropriately for each platform to isolate a project from platform specific jar locations etc. An example of this screen, with the JSF and ICEfaces entries expanded, is here :-

However, whilst you will see entries for plugins such as Eclipslink and ICEfaces on this screen, it does not provide any means of configuring them. Libraries for such plugins use an Eclipse feature called a Classpath Container. This allows the library configuration to be completely dynamic, as it is handled in code via a class. This allows the configuration to change at any time in response to project changes, as every reference to the classpath container is handled via the code rather than being static. To configure plugin libraries, therefore, you need to visit the dialogs for the Project Facets, which is where plugins are configured for the project. This post here, which details how to create a JPA-enabled EJB, shows this in action for JPA.

Another example would be to configure the  libraries for JSF and ICEfaces. You can do this as follows :-

Open the Project Properties dialog for the project, and select the Java Server Faces option under Project Facets in the left hand pane. This lists all the JSF and ICEfaces libraries available which may be selected/deselected.

The buttons on the right of the libraries frame allow management and downloading of the libraries. Clicking the Manage Libraries button allows configuration of the libraries available for selection in the project facets dialog above.

This is for example where you would upgrade ICEfaces libraries to a new version. You can leave both versions, or remove the old ones once you don’t need them any more. You can then select the new versions for that particular project in the parent Project Facets dialog.

Note that one particular issue arises when creating a new Eclipse workspace, as it is useful to migrate all the library definitions to the new workspace to avoid having to set them up manually or download them again. This post describes how you can do this by exporting and importing workspaces preferences. The post also discusses the issue of library location when sharing libraries – this is important as by default you would end up with one workspace sharing libraries within the folder structure of another workspace. My typical development folder structure is detailed at the end of this post.

If you subsequently return to view the libraries on the Libraries tab of the Java Build Path screen, you will then see the results of your efforts – the libraries for the plugins will have changed in accordance with your actions.

The dialogs used for plugin configuration do vary and are certainly not always intuitive or consistent – in these examples JPA was configured via the Java Persistence dialog in the project properties or via a link on the JPA facet screen which is not always present. In contrast, the JSF libraries (including the ICEfaces libraries) are configured via the Java Server Faces option under Project Facets. Even though there is an ICEfaces option under project facets, in my 3.5 Galileo Eclipse this displays “unknown library configuration”. However, the configuration is all there if you are willing to hunt around a bit for it!

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