I'm in the early stages of creating a new Eclipse plug-in in Eclipse 2019-06. I created the plug-in using the "Hello World" wizard option and created a debug configuration that successfully launches a secondary workbench for testing. I can click on my new menu option and step into my new code.
I want to use a modified version of org.eclipse.jdt.junit.wizards.NewTestCaseWizardPageOne, so I added the package to my project and edited NewTestCaseWizardPageOne. However, when I try to debug, the debugger asks for a source location. It seems to want to load the file from the local repository (.p2/pool/plugins/org.eclipse.jdt.junit_3.11.400.v20190510-0840.jar), rather than my edited version. Why is that?
There must be some kind of classpath problem, but don't versions of files in the project have precedence over those in the dependent plugins? I've looked at a number of similar questions (1, 2) and other sources, but I haven't yet found the answer. Please help.
Following Alexander Federov's suggestion, I converted my plugin into a fragment. This was fairly easy to do following the advice from this StackOverflow page. The main changes were:
Renamed plugin.xml to fragment.xml and changed the top level xml
element from plugin to fragment.
Added a Fragment-Host entry to MANIFEST.MF
The key advantage that this provided is discussed in an Eclipse Wiki
page:
... a fragment appears much the
same as a normal plug-in. A fragment can specify libraries,
extensions, and other files. When it is loaded by the platform loader,
a fragment is logically, but not physically, merged into the host
plug-in. The end result is exactly the same as if the fragment's
manifest were copied into the plug-in manifest, and all the files in
the fragment directory appear as if they were located in the plug-in's
install directory. Thus, a runtime library supplied by a fragment
appears on the classpath of its host plug-in. In fact, a Java class in
a fragment can be in the same package as a class in the host and will
even have access to package-visible methods on the host's classes.
The last part having to do with access to package-visible methods was what I needed. Thanks, Alexander!
Related
Just recently started using Eclipse and ran into an issue with exporting the plugin I'm working on. I tried to search but so far no luck - but if the answer is already here I'd be grateful if someone can point me to it.
I'm writing a n OSGi/Equinox plugin with Eclipse. The plugin is for a 3rd party system, which allows extensions: basically all jars placed in the application's plugin folder are automatically loaded into the application at startup. I have managed to put together my plugin, it's loading fine and it works.
The issue is that I rely on another plugin which is placed beside mine in the plugins folder. For obvious reasons I do not want to package that plugin into my plugin jar file. I have tried to add the dependency as an external archive, but this breaks the export: when I try to export my plugin project ant complains about missing dependencies and types. (If I actually include the other jar file in my plugin everything works, but obviously this is less then ideal.)
So: how do I set up my plugin project dependency, that it's a) an external dependency and b) doesn't need to be specified with a path or a variable - i.e. how do I tell my exporter to "don't worry, it will be there right beside you"?
Edit: Apparently there's an important detail I didn't mention. The external jar file I depend on is not an OSGi plugin, just a regular jar file with some classes in it. To the 3rd party system it seems all the same (all are under the plugins folder, all are loaded into the application), but for Eclipse the distinction seems important.
If you reference the other plug-in as a dependency in your plug-in's MANIFEST.MF the export should work without errors. The plug-in should be listed in the Require-Bundle list in the MANIFEST.MF.
You can do this in the MANIFEST.MF editor by adding to the 'Required Plug-ins' list on the 'Dependencies' tab of the editor.
Note: When referencing other plug-ins you must always use this method. Do not try adding the plug-in jar to the Java build path or anything like that.
If the jar you want to use is not an Eclipse plug-in you must should include it as part of the plug-in and list the jar in the Bundle-Classpath in the MANIFEST.MF. If you cannot do this you can reference an external jar in the Bundle-Classpath using something like:
Bundle-Classpath: .,external:$LIB_LOCATION$/lib.jar
. is the normal entry in for the plug-in code. external:$LIB_LOCATION$/lib.jar looks for lib.jar in a location defined by the environment variable LIB_LOCATION. This method can be difficult to get right.
In the end the solution to my specific problem was to add the external jar file as an Extra Classpath Entry on the build properties tab (this translated to a "jars.extra.classpath = .jar" entry in the build.properties file). I have also added the jar file to the project itself - after adding the extra class path entry that got changed into an external dependency automatically.
With these two changes I was able to successfully export my plugin, which didn't contain the external jar file, but was able to reference it when loaded into the 3rd party system.
We have an application developed in NetBeans, based on the NetBeans platform. There's a 3'rd party program that we have a runtime dependency on, more specifically a jar in the other progams lib folder.
How should we include the other progam's jar in our classpath?
The recommendation from the other progam's manufacturer is to set environment variable CLASSPATH to include
C:\Progam Files\Other Program\lib\theJAR.jar
And if that's not possible, we should copy theJAR.jar to JRE-HOME\lib\ext
We must not copy theJAR.jar anywhere else, that might cause it to stop working...
Now NetBeans takes no notice of what's on environment variable CLASSPATH. Their recommended way seems to be to make a wrapper, but that would lead to copying the jar, unless there's some way to make a wrapper module that points to CLASSPATH?
At the moment we are copying the jar into JRE-HOME\lib\ext. But then there's unnecessary hassle when we install some java update.
Do you have any solution to this problem? It seems like something that might be simple, but I haven't found the right place to look yet...
Edit: The application is ant-based.
From the documentation for the Module System API's overview of the runtime infrastructure (bottom of the page under the section "Common Problems and Solutions"):
Q: Can my module add a library JAR to the classpath from outside the
IDE [read: platform] installation?...
A: Not easily. You have a few options:
Add an entry to ide.cfg [your app's .config file]. For example:
-cp:a c:\eak\lib\eak.jar This startup file provides the ability to add classpath entries to the IDE's Java invocation.
...
It goes on to list two more options. The second option is the same solution you've come up with. The third is to "partition your module and use a new classloader" which I can't recommend either way since I have no experience doing this (but it's worth a read).
Assuming that this first option is what you are looking for, you will need to add a custom .conf file to your project and point to it in your project.properties file, like so: app.conf=nbproject/my.conf. This will add your custom .conf file to your app's install directory instead of the default config file that is normally added. Of course, you'll need to add the -cp:a c:\eak\lib\eak.jar entry to this custom config file in order to load the .jar.
During development you'll need to add the following entry to the project.properties file: run.args.extra=-cp:a c:\eak\lib\eak.jar. This will pass the command line option to your debug instance.
You can add that .jar file by following the steps below:
In the left side panel named "Projects" open your project and right click on the "Libraries", then select "Add JAR/Folder...".
Then select your .jar file from the location where you have stored it in the next dialog box that opens and then press "Open".
Vola Finished!!! (with the same process you can add other libraries also like JavaCV, JMF,etc)
And Now You Can Use That .Jar File From Your Project Library.
Hope It Helps.
I am trying to extend a third-party Eclipse plug-in by using a fragment project. The major reason is that the third party plug-in contains classes having the default (package) modifier and I need to extend them.
Thus, my extensions class must be located in exactly the same package. I create a fragment project containing the same package and put my class into it. Everything works fine when I am using a runtime workspace.
However, if I try to deploy my fragment (e.g., deploying it into the dropins folder of my Eclipse distribution), I am not able to execute the code. Extensions and stuff like that work fine (e.g., I use extensions for a new Run Configuration. However, if I try to instantiate this run configuration I get an error message that the third-party root plug-in was unable to load the class to display my configuration tab group.
Any experience with this kind of problems?
Sorry, but that does not work. Unless the host bundle has been crafted specially for it, you cannot override a class in the host from a fragment. The reason is that resources - including classes - are retrieved from the host before any fragment.
See org.eclipse.osgi.baseadaptor.loader.ClasspathManager for the implementation..
Actually, this is the extension code I am using:
<extension point="org.eclipse.debug.ui.launchConfigurationTabGroups">
<launchConfigurationTabGroup
class="com.android.ide.eclipse.adt.internal.launch.jouleunit.AndroidJouleUnitTabGroup"
id="com.android.ide.eclipse.adt.jouleunit.AndroidJouleUnitLaunchConfigTabGroup"
type="com.android.ide.eclipse.adt.jouleunit.launchConfigurationType">
</launchConfigurationTabGroup>
Of course, there are further extensions definig the launch configuration type etc. but this is the one leading to the class which Eclipse can not find.
Actually I found the problem now for myself. The problem was a wrong configured build properties file which excluded the Java byte code from my fragment JAR. Very itchy, as the classes were in the JAR but in a wrong subdirectory.
I'm going to try to give as much detail as possible here, pardon me if some is irrelevant.
I have two projects in eclipse. Project 1: com.myworkplace.parent, with code in the package of the same name. Project 2: com.myworkplace.child, with code in package of the same name (I moved my code to that package, from the default package, if that makes a difference). Both are located in my workspace folder and structured the way you'd expect them to be, as far as I can tell.
I've added child to the build path of parent in eclipse using Java Build Path -> Projects -> Add. Parent's .classpath file contains the entry:
<classpathentry combineaccessrules="false" kind="src" path="/com.myworkplace.child"/>
I add a reference to a com.myworkplace.child.Child class in parent, import it, compile it with no errors, run and get:
java.lang.NoClassDefFoundError: com/myworkplace/child/Child
What gives?
Edit: The parent application is an RCP app, maybe OSGI (I really don't know much about RCP and related stuff.) Some googling leads me to believe it might have something to do with this.
Since your application is an RCP app there is a difference between the eclipse classpath that is used while you are editing code and the OSGi classpath that is used at runtime. It sounds like you need to add the com.myworkplace.child plugin to the list of dependencies of the com.myworkplace.parent plugin.
Open either plugin.xml or META-INF/manifest.mf in the parent project. Eclipse should open the PDE plugin editor (a form based editor for the underlying config files). Click the Dependencies tab at the bottom and add your child plugin to the "Required Plug-ins" list on the left hand section of the form. Alternately you could add the com.myworkplace.child package to the "Imported Package" list on the right. The difference between the two is beyond the scope of this answer, but you can read about that in the eclipse docs now that you (hopefully) are moving in the right direction.
We found that even doing all the proper things in the eclipse rcp project, we were still getting such errors. The solution was to delete the application's workspace directory (by default it would store workspace settings under .eclipse, but we've tweaked our code to use another dir that is not shared with other eclipse stuff).
When we removed this dir after a rebuild, our app worked. Apparently it was storing the classpath somehow along with other settings, but we didn't investigate the exact details.
(NOTE: This applies only if you've called the IWorkbenchConfigurer.setSaveAndRestore method passing a boolean value of 'true' - which means that your application will save and restore various rcp settings after a shutdown of the application and subsequent relaunch.)
If your code is running in an application server, you need to configure the Classpath correctly for that application server.
To do that, find your Servers tab, double-click it, click Open Launch Configuration in the new tab that appears in the main editing area, click the Classpath tab and ensure the Classpath there is correct.
I downloaded the source code for the EMF based UML2 Plugin and changed a class in the org.eclipse.uml2.uml.edit project to remove special characters when returning string representations. Now when I export the projects and place the jar files either in the dropins directory or replace my current uml2 plugin jar files in plugins directory, The UML files are no longer recognized, in short my modified plugin does not install correctly (no error is thrown and I can see the files being picked up under Plugins->Target Platform) .
However, When I run the plugin as an eclipse application (from the workspace) I can see the changes I made being reflected in the new instance of eclipse.
What can I do to ensure that the plugin installs correctly?
Is there a documented procedure of how to build the uml2 plugin (or any comparable plugin) after modification?
Select the project and open the context menu. There is an entry PDE near the bottom of the menu. In there, you can find an entry to build the plugin for deployment. This gives you the features and plugins directory with the fixed files. Copy both into your Eclipse install.
Unless the UML2 plugins require some kind of magic build script, exporting the one plugin you changed and overwriting the original in your Eclipse installation should be the easiest solution. One potential problem which comes to mind is conflicting plugin version numbers: make sure you don't have two identical versions of your modified plugin in your Eclipse installation.
When debugging plugins which apparently don't work properly at runtime, I always look at Help > About Eclipse Platform > Configuration Details. This lists all the plugins found by Equinox during startup, along with their status (see the Javadoc of the org.osgi.framework.Bundle interface for explanation).
I faced the exact same problem as you describe here . I dont have any answer to your problem but i am sharing what worked for me .
I created a local update site of the plugin on my system. Create update site for your plug-in article explains very very nicely the steps needed to accomplish this .