Eclipse CVS ignores .class files -- how can I turn that off? - java

I would like to commit new .class files into CVS via Eclipse, but these files get ignored, and I'm not sure where to turn that off. The Preferences windows a section for doing this, but .class isn't listed.

Preferences > Team > Ignored Resources
Also, change to the Resources Perspective to see all files.

First of all I'd like to echo the sentiment of the other answers, in that checking the compiled source files into source control is a very bad idea, as it means any time someone makes a change to the source, they'll have to remember to checkin the corresponding class file.
Regarding your specific question, this page states that all generated .class files are automatically marked as derived, meaning they won't be checked in automatically:
Any resource marked as derived will be automatically ignored for version management by Team CVS. Some builders, such as the Java builder, mark all of its build output (e.g. .class files) as derived.
To my knowledge there no way of changing this, which should underline that this is a bad idea.

I ended up figuring it out... it's a little odd: You have to go into the Preferences window (Team -> Ignored Resources) and add ".class" as an ignored resource, then uncheck the check box.

Are you really sure you want to be checking compiled files into CVS? I've never worked on a project that does this - it is a bad practice.
You should only really store source code in CVS, not the files generated from the source code. There is no true need to check these in because they can be re-generated from source code at any point in time.
By checking in the output of your source code, you're only going to introduce the possibility of headaches due to someone forgetting to check a .class file in, etc.

If anyone is still interested, although I absolutely agree it is a bad practice to check .class files into CVS, sometimes I think it is reasonable.
For example, in my case I have an application that contains an EJB 3.1 which has to be called by an external agent (ControlM). As the EJB is called by a remote process the generated stub (.class) is needed. In this situation, I checked this generated stub class into the CVS because I want it avaliable for all the team members.
What I do is the following:
Open the Navigator View. (In this view all .class can be viewed by
default)
Select the .class / right click / Team / Add to Version Control
Accept the warning saying that you are going to add ignored
resources
Now the .class can be committed as usual.

Related

How to import JAR file as a project into an IDE?

I have a Maven project. After I make changes to the project, I package the project up into an Uber Jar file and upload that to my backups. I am wondering, if my computer were to break or I lose all the code to the project, can I get the project back using only the Uber Jar file or would the project be gone forever?
How can I open this Jar file as a project and view all the Java code inside of it?
It would be entirely gone; that jar file contains only class files, not your source files, and you can't 'recover' source files from class files (you can decompile them which is mostly useless for this purpose; all comments, most names, most structure - all gone. You can't feasibly continue your project with this).
As it isn't in there, it's not possible to 'open a jar file and see all java code inside it'.
You'll need to set up backups.
The proper way forward is to first set up version control; this ensures that you don't just have a backup of the latest state of your source files, but every state of it - you can travel back to any time. Protects against code you deleted by accident, and means you can freely remove code you think you no longer need without that nagging feeling of: Yeah but what if.... maybe later? - so stop commenting out stuff you don't need, just get rid of it. It also means if there's a bug, you can time travel to the exact point in time when you added the line, and you can review the changes made by others in a project (presumably you're writing this on your own for now, but at some point you'll work with more people than just yourself!)
Read up on git which is the version control system that 80%+ or so of the community uses, probably best not to spring for exotic options if you aren't familiar. There are a billion tutorials out there to find if you search the web.
Host your git on a site like github or bitbucket which therefore also takes care of backups. Alternatively, host it on your own server (it's not complicated; git is open source). If you can't do that either, just let git write to a local directory and then use e.g. backblaze or something similar to ensure that file is backed up.
Yes, you can view your code by using a decompiler. I have experience mostly with IntelliJ, and this IDE includes a decompiler of its own. In case you lose everything and have only the jar file. You can use this included decompiler to get your source back from your .class files. But instructions on doing that are a story for another question...
If you want to secure your code use GIT. A version control tool that is a must when it comes to programming. Google about it and after a few days of playing around with it, you will never worry about such things.
Right-click on your project.
Select Build Path.
Click on Configure Build Path.
Click on Libraries, select Modulepath and select Add External JARs.
Select the jar file from the required folder.
Click and Apply and Ok.

IntelliJ IDEA - Decompiling/Editing/Recompiling JAR

I realize this may seem like a completely stupid question and this question is a "wall of text", but I'm feeling like I've gotten way out of my depth here and need some guidance. I've read several SO questions on this topic, but still can't seem to find one that addresses this particular situation. (please reference update(s) at the end of this post)
BACKGROUND
Our company has an application that was built in Java and released as an executable JAR package by a developer who passed away a couple of years ago. Since then, there has been minimal need for even looking at that code, let alone making any changes. That's been really good because I do my programming in VB.NET (Visual Studio) and, while I can read and make sense of Java code, I'm not proficient in actually writing/debugging that code.
However, a recent issue has come up that forced me to try to take a look at this Java code due to some internal changes in organization and data structure. I've looked in his "src\" directory and found older versions of his original code but wasn't able to find the most recent version anywhere. I found some code that made it possible for me to extract the JAR that's currently being used to a local directory on CodeProject (JarsVB), so I've been able to look over some of the .java files when trying to figure out what query is being used for some random operation. I don't know what tool(s) the original developer used to create the project/JAR, so I've installed the IntelliJ IDEA Community Edition 2018 as an IDE, and it's worked for me so far to simply view the code so I can understand a bit about what it's doing.
PROBLEM/GOALS
Unfortunately, now there is a need for me to make a change to the Java code and update the JAR, and this is where I can't seem to make heads or tails of what I need to do. I have my local copy of the code from the "unzipped" JAR containing all the .java and .class files (along with all the other resources), but I'm not sure how to go from that to modifying the code and recompiling the executable JAR.
So, my goals here are as follows:
(properly) Decompile the existing executable JAR. (If the JarsVB solution I mentioned above did what it was supposed to do, I should already have this part handled, but if there's a better, more "integrated" way of doing it, I'd be open to that as well.)
Modify one or more .java files. (I believe I can figure out the syntax well enough to get this part done.)
Debug/test my changes.
Recompile the changes into an updated executable JAR for release. (THIS is where I'm experiencing the most confusion.)
WHAT I'VE DONE
I've been looking at the documentation for IntelliJ to try to figure out how to make this all happen, but I feel like I'm missing stuff. I set my "Project Structure" settings to point to a specific folder, but I can't seem to get it to actually build anything in my specified path.
I went into one of the .java files and made/saved a small change to test, then went to the Build menu and tried all the building options available to me: "Build Project", "Build Module", and "Rebuild Project". Each time, the event log shows that "All files are up-to-date" (even though I changed one), so I go to my output directory to see what it built, but the folder is empty.
I looked at the IntelliJ documentation for Packaging a Module into a JAR File, which says to
On the main menu, choose Build | Build Artifact
But that option is disabled in my Build menu, and when I look in the Project Structure dialog, the Artifacts section is empty, so I try to add a new setting (Add -> JAR -> From modules with dependencies...), but I'm not sure how to properly set that up either.
I tried to select a Main Class from my classes/ directory, but it wouldn't actually accept any of the .class files I selected, so I just left it blank. Then, I did a search for a MANIFEST file, but couldn't find one anywhere so I left that blank as well. The Build menu option is enabled now, but when I tried to Build Artifact, again, I get nothing in my output directory. In fact, the only files I can find that have changed are in my local working directory. I'm just dumbfounded at this point.
FINAL THOUGHTS/QUESTIONS
I've tried to provide as much detail here as I could think of about all the things I've tried and gone through to get this JAR updated, but if there's a question about anything, please let me know. I'm not looking for a "handout" and I don't expect anyone to do this for me, but I'm also not wanting to become a Java developer just for the sake of making some minor changes to an application that will eventually be replaced by a .NET application. I simply am not familiar enough with the tools or Java development in general to know how to get to where I want to be from where I am.
My decompiled source files are in a totally separate directory from the original, production JAR file because, when I recompile this time, I want to completely recreate the JAR. Am I understanding the Java development process correctly in editing one of the .java files I got from decompiling with the JarsVB and then recompiling the JAR?
Thanks in advance for any assistance in finding the resources I need to accomplish these goals.
EDIT/UPDATE
So, looking at the link in the accepted answer in another SO question, How to build jars from IntelliJ properly?, I figured out at least one part of my issue: Leaving the Main Class setting of my Artifacts configuration blank was a problem. Since I hadn't been able to select a .class file and I wasn't sure how to correctly populate that field, I hadn't given the IDE enough information to operate correctly. I entered the namespace and class (namespace.class) I found in the class file that apparently defines the main method for the application, then set the path for the MANIFISET.MF file to my output directory and tried again to Build Artifact.
This time, at least, it DID produce a JAR in my defined output directory, but it's only 1KB in size. As stated above, the source files are in a completely separate directory from the original JAR file from which they were decompiled. The output directory, too, is completely separate from the location of the original JAR file. Do I need a copy of the original JAR file in the output path for recompiling to work correctly?
I'm making progress, but I'm sure I'm overlooking something "stupid" at this point that's primarily due to my unfamiliarity with the IDE and developing Java applications in general.
UPDATE 2
Looking at another SO question - how to create jar of java package in intelliJ idea - I learned that I have to individually add the necessary files for repackaging into the JAR. However, this brings up the question, what files do I add? The linked question identifies the .class files, but when I go look at the .class files in my working directory, none of those have been updated recently, so it looks like I'm still missing a step somewhere.
Another question this brings up is, are there certain conventions for Java development of which I need to be aware when preparing my environment? I have my output path set to a completely separate folder than any working or production code, so I'm wondering if something in that setup might potentially cause issues.
As I said before, I made a small change to one of the .java files, then tried both the Build Module and Rebuild Project options, but those are still telling me that "All files are up-to-date". Even so, I tried adding just the .class files from under my classes\ directory to my Artifact configuration and tried again to Build Artifact. I got a bit larger file (approx. 5MB), but when I try to execute the JAR, it just doesn't appear to do anything, let alone actually launch the application.
I tried again by adding the root folder of my local copy of the source adding everything the root folder contains. (yes, the directory probably needs some "spring cleaning", but that's for another day)
This time, I got a much larger file this time (approx. 21MB), so I thought I might have fixed the problem. Unfortunately, no such luck. The JAR still doesn't appear to execute.
For reference, the original JAR file from which the code was decompiled is approx. 59MB in size so, either IntelliJ is doing an incredible job with compression, or there's yet another step I haven't yet found. I'm sure this is all a matter of getting my IDE configured correctly, but I just can't seem to find the right combination of settings.

How to step onto/debug imported java code in netbeans

I have been searching for a long time on how to step through imported code classes in netbeans with no solution.
When debugging or stepping into the code, netbeans does not highlight and stop at the imported code classes being used. This is extremely inconvenient since the code I am working on is complex and stepping through is the only way to fully understand it.
I created a new project with existing sources. I have made sure that under window>debugging>sources I have added my working folders.
I also made sure the sources were added in the "runtime" classpath.
The compile classpath appears to be empty, I'm not sure whether that has something to do with it.
MORE INFO: In the debugging window while the program is paused, the main method profile from my imported class says it is reading from "Hidden source calls", but it is really just the normal imported code.
Why is this happening? Can anyone please help?
Folks,
One of the reasons you can get Hidden Source calls is adding in existing packages and java source code at the wrong directory level. You MUST add in the parent directory of the package not the child directory that represent the package name,
example if you have /home/torsi/java/src/torsipackage/com/main.java, you need to add in src, not torsipackage, you will now you made this mistake if you see listed in the top-level package name for your package.
Tom
Well I've not heard the term "Hidden source calls" before but I wonder if you're trying to step into third party code? If you want to step into compiled code it must have source associated I believe. I think it's possible to step into native code because they include the source somehow in the distribution for that exact reason. If you want to step into a library that's been developed by some other private entity you will likely not be afforded that luxury unless it's open source, and even then you may have to retrieve the source first.
Ultimately my point is that there is a difference between a .java file and a .class file. I believe it's possible to reverse engineer .class files but haven't done research on the topic.
If you want to step into code you didn't write odds are you'll need to change your code to work with the imported library or alternatively file a bug report with the developer.

eclipse java annotation processing commit generated java classes with subclipse to svn

I'm using Java annotation processing to generate a couple of Java source files. I enabled it on the project specific settings (Properties -> Java Compile -> Annotation Processing). The generation works fine and the classes end up in the .apt_generated source folder.
Unfortunately, I'm not able to commit the generated Java source files with Subversive to the svn server. If I selected the .apt_generated source folder and perform Team -> Add to Version Control ... the dialog doesn't list any files to commit. So far, I have been committing .apt_generated source folder from the command line. Can I customize this behavior? I wasn't able to find anything on this in the team preferences.
I'm aware of the option adjusting the headless build. Since my files won't be changed to often, I just would like to commit the generated files for the moment. Thank you!
The reason for this behaviour can be found in this thread: Subversive doesn't allow to commit "derived" resources. The folder used by the annotation processing and all contained resources automatically get the "derived" flag, which you can verify on their Properties->Resource page.
I'm in a similar situation as you wanting to commit generated files at least initially. There is a plugin that apparently makes it possible to override the behaviour of setting the "derived" flag, which I'm going to test now: AutoDeriv
Since this has been unanswered for over a year, I'll take a stab at it. I had a similar problem with Eclipse's .project and .classpath files, which I wanted maintained in Subversion.
I believe you may have to tell Eclipse not to ignore "resources." These are files that have extensions but no names (e.g. .project or .classpath or .apt_generated). From Eclipse's Project Explorer click on the View Menu icon (the upside down triangle icon). Then Customize View... then remove the check from the checkbox labeled .* resources.

Files edited outside the ide

If I run a script to edit files outside of the ide I am using, will the ide recognize the changes made to the files?
More specifically:
-IDE: Netbeans 6.8
-Version Control: CVS
-OS: Windows XP
In general, yes. But the form designer of NetBeans considers some parts of the code "private", and you shouldn't modify these parts externally. They are identified by comments in the generated code:
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
These parts are in fact generated from an external proprietary .form file, and having the source code not aligned with the .form code will mess everything up.
Yes it should. Give it a whirl and check it out.
Yes, with some caveats:
If you have those files open, edited, and unsaved in the IDE at the time, then you will need to tell the IDE whether to discard or keep your in-IDE changes.
If you have them open and unedited, then depending on the IDE, you may have to tell it to reload those files (the IDE should warn you that the file has changed since you last opened it).
If you move files around, and your IDE has some kind of project file (that tells it, among other things, where all the files are) and you don't update it accordingly, you may have problems.
Any files that you don't already have open in your IDE should behave as expected, and I would consider it a bug if it didn't pick up the changes.

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