I'm a bit confused with NetBeans (versions 6.5 and 6.7). I have a NetBeans Module Suite application, which consists of several NetBeans Modules. I need to add some code in one of the modules. The new code is using a library, distributed as several jar files.
The problem is, that NetBeans does not allow me to add this library jars directly to the classpath. It wants to wrap all the jars in a new Library Wrapper Module, which is then added to the project and used from there. The effect is that all the original jars are combined into a single new jar automatically by NetBeans. This is a problem, because I can't just replace the jars later, without rebuilding this "Library Wrapper Module" and the original library is updated nightly.
I read some NetBeans forums, but I found nothing... I tried with simple java application, where it is possible to simply add jar(s) to the classpath using Project Properties -> Libraries -> Add JAR/Folder. If you use a NetBeans module instead of a simple application, the Libraries dialog looks different and does not have the "Add JAR/Folder" button.
Is it possible to add a plain normal jar in a NetBeans module and how?
It looks like the way a user can wrap a jar has changed in NetBeans 6.8.
Since this has been integrated into a property dialog of a project, the build process might be smarter, too. And it seems like that was your primary concern....
Related
I want to create a multi-module Java project, in NetBeans 15.
By "module", I mean the Java-9 "modularity" feature, where each module folder has a module-info.java file that specifies its exports or depends or etc.
I know how to code a multi-module application. I just don't know how to do it as a NetBeans project. Yet I'm sure that lots of you StackOverflow readers have been there, done that. How can I do that, too?
Also, I am not using a plug-in, I am not using JavaScript. I am not using Maven, but Ant would be OK.
There is a complete tutorial at https://netbeans.apache.org/tutorials/nbm-projecttype.html, but this shows how to create a NetBeans module, for the NetBeans IDE, so that is the wrong place to look.
Got it! I've succeeded, I built a modular project in NetBeans.
But first, I had to understand how modules work in Java. I kept my coding as low-level as possible. I used only non-IDE file explorer, NotePad++, and Windows Command Prompt. Instead of automating the process with CMD scripts, I stuck with Java's own #argfiles. The strategy was KISS (Keep It Simple Stupid), even though the typing was brutal, I really really had to watch where and what I was typing. And plenty of times, I wished I had the NetBeans "Tools" and "Edit" features. But finally I am ready to turn to NetBeans.
Yes, NetBeans does modules!
Follow these steps:
New project > Java with Ant > Java Modular Project.
Project Name and Location is your choice.
In the "Projects" window, right-click the name,
New Module, and add the module name
In the default package, right-click, and
add your packages
add your classes
code your module-info
another New Module etc etc
eventually you'll get your modules in. NetBeans is good at catching typo's and missing items.
run your multi-module program!
All this procedure is almost as easy as writing a non-module program. The extra layer of modularity should be logical and functional. For my project, I had to think twice about module boundaries and names.
So! It's working. The NetBeans IDE and debugger are working for me.
I'm trying out Java 9 Jigsaw module system (no module experience yet) and would like to use it for capsuling the classes within my project, but it's confusing.
According to this article it should be possible to have multiple modules within ONE project. I made a new project in Eclipse Oxygen (Java 9 is supported) with the same structure as shown in the article. But Eclipse keeps telling me that I must not have more than one module-info.java in a project.
I really don't know how to tell Eclipse that it should use the "multi-module-mode". And I really would appreciate not having to create a new project for every single module.
This works:
This not:
But according to this article something like that should work:
And how about deployment of a modularized project with Eclipse? There is nothing to see about the new jmod extension. Do I still export it as a runnable JAR file like before?
Notice that my questions refer to working with the IDE (no command line, I mean with an IDE that should be possible, right?) Thank you for enlightening me.
Currently, Eclipse requires you to create a separate project for each module (e. g. because each module has its own Java Build Path).
To understand this design decision, consider that Java modules correspond to OSGi bundles / Eclipse plug-ins and it has always been to have a separate project for each bundle/plug-in. If you come from the Maven world, you would probably expect a deeper folder structure instead. But modules are self-contained and combining several modules into one project would only add an additional folder level without meaning. However, Eclipse supports nested projects and so-called working sets if you need an additional folder level.
Exporting modules as images is planned for Eclipse 2019-03 (4.11), on March 20, 2019 (see Eclipse bug 518445). Exporting modules as JARs that can be used on the modulepath (-m) already works (see my video).
I don't know if this question is still open for an answer, but you can solve this problem by simply removing all source folders on the build path. At least this works for Eclipse 2021-12 version.
As you can see this is a demo project from the Official Gradle Guide Book and it has multiple modules. Each module has its own module-info.java.
project structure in IntelliJ IDEA
If I open this project in Eclipse it will give me the 'duplicated entries on module-info.java' error.
Eclipse shows the error
But if I delete all the source folders on the build path, the error is gone and the project can be built and run without problem.
project properties: Java build path
The only problem is that you have to build the project with Gradle so that it will produce the .jar of each module and you have to include them in the libraries later.
include all the .jar in libraries
I think this is probably the same solution mentioned by howlger above.
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.
Greetings,
I have a java project which I export as a jar. This java project also uses JNI.
So far, the only method I could find to use this jar in an Eclipse plugin is to wrap it in an other eclipse plugin project, and add this jar wrapper plugin to dependencies of my actual plugin.
I've wrestled with Eclipse's paths and dependency settings for days, and this method is the only one that works for me at the moment.
However, it is not very practical, since when I change my JNI based java code, I can simply create a new jar, but to connect that jar to my actual plugin, I have to re-create the jar wrapper plugin every time.
That is, I delete the jar wrapper plugin project, with everything on the disk, and re create it with the same name, pointing to the updated jar. I also have to drop the reference to this project from the actual plugin project and add again (maybe this has gotten smarter recently, but I did not test it)
This is time consuming, and I can't add this wrapper plugin project to svn either, since it is being created from scratch every time.
If I could simply update a jar wrapping eclipse plugin project by pointing at the new version of jar, that would solve my problem, and I could commit the project to svn after each update.
Is there any method you can think of which may help me run this process smoothly?
Best Regards
Seref
An Equinox-only (i.e. non-standard OSGi) method of using external libraries in an OSGi bundle without physically wrapping them is bundling by reference: you still need a wrapper plugin, but it does not contain the wrapped library itself but a reference in the bundle manifest's Bundle-Classpath header with a syntax like this:
Bundle-Classpath: external:/path/to/your/lib.jar
During development time, this is quite convenient and saves the effort of having to recreate the wrapper plugin whenever the wrapped library is updated. During deployment time, you'll either have to install the library along with the product or use a traditional wrapper plugin (one containing the actual library). You can also use the same wrapper plugin for bith use cases, but change the Bundle-Classpath from external:/stuff/lib.jar to libs/lib.jar dependent on whether you want to use the wrapped or the external library.
(Most of this comes from the book OSGi and Equinox - Creating Highly Modular Java Systems, which I don't really like, but which nevertheless contains useful stuff about Equinox (Eclipse's OSGi implementation) and the PDE build system.)
Is there a way to add a dynamic library folder to a plain Java project similar to WEB-INF/lib in a Dynamic Web Project?
I mean, can I specify a simple folder, let's just call it lib, and have Eclipse monitor it for any library jars I might want to add or remove.
Currently I only know this behaviour from the Web App Libraries where any jar you copy into WebContent/WEB-INF/lib is automatically added to the class path, but in "regular" Java Projects I need to add every jar by hand.
Yes and no. It requires writing a suitable extension to the org.eclipse.jdt.core.classpathContainerInitializer. If you're in the Package Explorer, though, you can just select all the jars within the View and use the context menu to add/remove them to/from the Java Build Path.