Ok, this is really weird. I wrote some codes a day ago, and then edited the codes. Then after hours and hours of editing and rewriting and introducing new classes, I ran the codes, but then I go a response from a "System.out.println()" line that I had long removed. Basically, netbeans seems to be running a much older build of my codes. I've cleaned and re-built my codes and still nothing. It keeps running old codes.
What's going on?
In Neatbeans by default settings will run your new code, even if you not build the project again (given that you have not modified the build settings). You can clean and Build the project again. If this also not works, just back up your codes and create a new project and include the source codes and run the project.
Maybe you can try to clear netbeans cache
close NetBeans
delete cache folder (/home/user/.cache/netbeans)
open the project and wait for scanning project to finish
I had similar problem. I hit "Clean and Build", and then "Run", and it worked.
if clean and build didn't do the work for you try SHIFT+F6 rather than just F6 as a shortcut for RUN .That was the case for me and it works now just fine.
Well, Clean it well! Check for any read only folders in your bin that prevent overwriting of class file. Go to classes folder and check date and time class files got modified.
Related
I'm using Eclipse Mars 4.5.0 IDE, and developing ColdFusion applications using CFEclipse plugin. Also, I have SVN Subversion and FileSync plugins.
The company, which I work, has a huge repository. I synchronized all files to the my own workspace and when I do any changes in Eclipse it should update my own workspace and development folder in our server.
It works fine, but sometimes, let's say once a week it starts to build workspace automatically. As I said workspace is huge, so it takes forever.
I cannot do any changes while it was building. Actually I can change the codes but I cannot save the file, saving task is just waiting to build workspace. When I cancel the building task, then try to save the code, before saving building workspace start again.
It's really annoying. I cannot do any work, I have to leave my computer at the work, when I came next morning building is done, and I can start to work. I tried everything to get ride of it, none of them worked.
Also project build automatically is unchecked. But when I do chances in the code, I have to build project not the workspace to sync the code to the development. But of course it builds all workspace not just project.
Interesting thing is that it is not happening all the time. Sometime it works fine, sometime not. For example, yesterday, I just copied one folder from one project to another one, and tried to build project, but Eclipse build whole workspace. I don't know what to do?
EDIT: Screenshot is added.
Have you tried unchecking build automatically in
Window/preferences/general/workspace?
EDIT:
similar question has been asked before on SO.
The answer was (as far as I can understand) to make jar-s out of projects that you use but don't want to compile them every time.
Make sure you have unchecked the option Build Automatically under the Project menu.
My Eclipse installation suddenly stopped showing import suggestions. If I type a class name that isn't in the current package, autocomplete works fine and shows the class, but after picking from the drop-down, the class name is highlighted as an error with the message "MyClass cannot be resolved to a variable". This error shows no Quick Fix suggestions. However, if I manually add the relevant import statement at the top of the file, the code compiles and runs fine.
I've checked my build path and everything appears to be in order -- and like I said, the code runs when I hand-jam the import statement -- but losing automatic importing is really slowing me down. Any idea what could have gone wrong? It worked fine last week!
ETA: Another note, if it helps: F3 still opens the class declaration, so Eclipse clearly knows what I "mean", even without the import statement.
Also also: Things that have not helped:
Clean all projects
Restarting Eclipse
Restart computer
Delete .metadata from workspace, re-import project
Start new Java project, re-link source folder, re-add dependencies (not using Maven, but that's not my choice)
Thanks for all the help, everybody, but this turns out to have been a case of a broken Eclipse install.
I still haven't figured out exactly how or what was broken, but I tried to make a new project with a single "Hello World" class. The New Class wizard errored out with "Creation of element failed" in the class org.eclipse.wst.jsdt.internal.core.dom.rewrite.ImportRewriteAnalyzer. Once I hit "internal errors" in Eclipse, I gave up and installed a fresh Eclipse from a new download.
With a new Eclipse, I got my Quick Fix suggestions back, as well as automatic imports. I guess in future I'll try reinstalling Eclipse before I go looking for solutions to obscure errors like this :-/
These kind of situations can occur if your workspace went into a bad state or eclipse was unable to properly save state during last exit of workspace.
Try Project > Clean and clean all projects and rebuild all. See if this helps.
Clean all your projects. Then update Eclipse. Then restart of Eclipse. Then restart your development PC.
This happens to me sometimes too, I follow these steps and the problem always goes away.
If none of the other answers works, one brute force suggestion which sometimes resolves weird issues like this would be:
Close your Eclipse
Delete the .metadata folder inside your Workspace folder
Restart Eclipse
Note: This way you're going to lose all your workspace configuration. I advise you to backup it first in case it doesn't works.
I know this question may seems stupid since i cannot give a lot of infos about it, but I think that the problem has to be some kind of bug...
I have written a java program whith NetBeans 7.1, which now gets me this error when trying to run. 10 mins ago it was perfectly running, and i have changed nothing to the class the error refers to
Could this be some kind of NetBeans error? Maybe it is a well know problem?
It also got this exception in NB 7.2
'clean an build' and restarting NB didn't work
updating NB with the latest updates and performing 'clean and build' also didn't work.
So i renamed the cache directory:
c:\Users\userabcd\AppData\Local\NetBeans\Cache\7.2\index\
started NB, waited for it to finish 'background scanning' and pressed 'Debug project' and voila. The cache gets corrupted every once in a while :-/
EDIT: Added Solution B below.
Solution A:
Project Properties
Build >> Compiling
un-check: Compile on Save
Clean and Build
Notes A:
If you leave Compile on Save un-checked, you won't have this problem any longer for this project.
If you enjoy the benefits of the Compile on Save feature, you can re-check the option after you clean and build, and continue work on your project as normal.
Compile on Save is meant to save time by constantly recompiling your .java files into .class files in the background as you save changes to your source code. That way when you build or run your project, most of the compiling work has already been completed allowing you to run and test your code quickly, even for large projects.
NetBeans uses some fancy caching and versioning to avoid having to recompile your entire project every time you save a file. That's why the other solutions listed here will often work; they are ways of defeating this caching-and-versioning system when it occasionally fails, as it has above.
Solution B:
Create empty folder e. g. C:\Temp\mine
Create a new shortcut for NetBeans
with command line parameter in Target:
"C:\Program Files\NetBeans 8.2\bin\netbeans64.exe" --userdir "C:\Temp\mine"
When compile errors occur
(ClassNotFoundException, MethodNotFoundException, etc...)
delete C:\Temp\mine\var\cache
Notes B:
You'll lose all your NetBeans settings the first time.
Much easier to solve future compile errors caused by caching bugs.
Allows running multiple copies of NetBeans, one per userdir.
I got also this exception. My solution was:
edit and save mentioned class (.java file)
clean & build project
deploy to tomcat server
I just had this happen to me with Netbeans 7.4 Beta.
Things I tried:
Restarting Netbeans.
Clean and build.
Shutting down netbeans, renaming the cache dir, starting netbeans and waiting for scanning to complete.
What worked for me:
Making the source file writable and saving a meaningless change (inserting a space).
I don't know why any of the other steps didn't fix the error. Maybe it would have worked if I had done a clean and build after renaming the cache dir?
Its a very frustrating situation to be in - Hopefully this helps someone (perhaps a future me?).
The JDK says for ClassFormatError:
Thrown when the Java Virtual Machine attempts to read a class file and
determines that the file is malformed or otherwise cannot be
interpreted as a class file.
Perhaps a class file has become corrupted. I am going to do the standard IT support statement.
Have you tried restarting NetBeans?
Hope that helps
Got right the same thing with Netbeans 7.1.
Working on a project that works fine for several months.
Now I changed a bean which gets persisted with javax.persistence and now this exception got thrown. Reverted my few changes, clean and compile the project, reboot the whole system: still exceptions.
The curious thing about it: the generated .war works perfectly in a Tomcat at another machine.
UPDATE:
Today I got the same problem again and I couldn't recall how to solve it, but I found this post again. ;)
After a half hour I found the solution: Just change value of the property serialVersionUID, redeploy the app and then you can change the value to its original value and redeploy again -> working.
Seems like Tomcat is holding that class somewhere deep inside – deleting working directories didn't led to success.
I've been trying to open Eclipse to start my work today, and it freezes everytime during load.
My Eclipse is Helios. Someone told me I should remove a file called .lock from .metadata folder, but still didn't work.
Does anyone have any idea of how do I "melt" this thing up?
ps: I opened it yesterday with no problems.
Have you already tried to start Eclipse with a -clean parameter? Sometimes this can resolve some issues..
I would suggest a (big) problem with a plugin in Eclipse.. because project plugins or runtimes will execute later.
Create a new workspace and repimport your projects from your old workspace. If you have a vcs, you can re-checkout them.
Start it with the -clean option.
It should take a bit longer (depends on your eclipse configuration and workspace, but if nothing is really broken, it will get it to work).
I believe something is wrong with your workspace. I typically remove current and create new one in such case. It usually takes up to 5 minutes (if I have to add 20 projects). In most cases it takes less.
I have experienced something similar when launching Eclipse after having to force close it for some reason.
If it always hangs when loading the SVN plugin — like in your screenshot — it is likely to be related to that. In this case I suggest the following:
back up your current workspace
launch Eclipse with the -data command line argument to specify a different workspace folder
if Eclipse starts up successfully, try to import your projects from the original workspace or even better from SVN
Today I see a strange behaviour of Eclipse 3.5.2 for the first time in 3 months.
First, when I run a main function, it runs a previously compiled version. Let's say I press Ctrl+F11 in the window with an open java class and existing main function. Usually it rebuilds the class and runs a new version. Today even if there was a compile mistake, it would run fine. So I guess it does not recompile the class.
Next, more strangely, if I intentionally make a mistake in the code and Eclipse underlines those lines in red, still the project Explorer does not mark them as containing errors. They remain of grey color if there were not any errors.
First I did not know how to solve this problem. I tried to reopen the project, restart Eclipse and finally reboot the OS. After the tenth attempt, after rebooting, Eclipse said that all project's files are "OUT OF SYNC with the file system". When I pressed "Refresh" - F5 on a project's header name in Project Explorer it finally marked all the files with errors as containing errors and running the main function gave the desired result.
An hour of my work passed and this happened again , with the other project. All the same. No marking of files as red, running no matter what old version of class with no compile errors.
And since Eclipse does not tell that files are out of sync, simply pressing F5 on a project cannot help.
What can you suggest?
When you select a project in the Project Explorer view and press F5, Eclipse should traverse the entire directory tree for the project checking that all files and directories all in sync. It does for me ...
The only thing I can think of that would cause this not to work is if you have file system timestamp anomalies. For example, if a file in the file system is updated but the file's last-modified shows that it was updated in the past. This kind of thing can happen if your machine's system clock is moved backwards or forwards at an inconvenient time. If you think this might have happened, try closing all projects, restarting Eclipse and doing another F5 refresh.
(I used to run into Eclipse synchronization issues a lot, but I put that down to a combination of flakey plugins and doing builds from the command line. Either F5 or Project>Clean usually works for me.)
It is also worth checking that you haven't turned off "Build automatically"; see https://stackoverflow.com/a/2818290/139985. This is not a "refresh" problem, but it would be easy to confuse it with one.
Is Build automatically on? (Menu > Project > Build automatically)
It happened to me because there was a cyclic dependency between two projects. Each project had the other on its build path.
Solution: Reimport the project
It happened to me when checking out a new file from svn in explorer. Eclipse could not find the new file for some reason.
I tried refreshing the project(F5) and Project > Clean and build the project(Project > Build All) none of these worked for me.
So I deleted the project from the Project Explorer view(Not from hard disk). Make sure you unselect "Delete project contents on disk(cannot be undone)" checkbox and save any unsaved changes before you do this.
Now reimport the project using File > Import option. That should work in most cases.
If you use gradle, or something similar, instead of reimporting a project you can just regenerate the project files (gradle eclipse for example), and then you can refresh the project. Less cumbersome than deleting and reimporting.