I am having a problem with Eclipse where I can run my program just fine, but when I try to start the debugger, I get this message
The picture is a little hard to make out, but instead of getting the normal debugging window, instead it says it is throwing a ClassNotFoundException, and is trying to dislay the source for Launcher$ExtClassLoader.
The thing that really baffles me though is that I can run the code just fine, it is only when I click the debug button that I have the problem.
I have also tried debugging at the command line with JDB, and I got the same error.
So far, I have tried Reinstalling Eclipse and downloading (what I believe to be) the correct Java Development tools for Mac OS X.
I have no idea what else I can try, so any help would be greatly appreciated. Let me know if there is any other information I can provide.
Source not found might be legitimate for dynamically loaded code (e.g. Maven).
There are three workarounds known to me (after months of search):
Connect to a running JVM with the debugger and you will see the code.
Use Dynamic Source Lookup plugin for Eclipse from here:
https://github.com/ifedorenko/com.ifedorenko.m2e.sourcelookup
Use run-jetty-run Maven plugin
http://code.google.com/p/run-jetty-run/
I prefer and recommend 3. It works and starts webapp much faster than jetty:run.
Unfortunately 2. didn't helped me as it has issues with Windows paths with spaces.
I have filled an enhancement request on Eclipse Bugzilla and if you agree this issue "Source not found" should vanish forever, please vote for it here:
https://bugs.eclipse.org/bugs/show_bug.cgi?id=384065
Do you have the sources for the files that you are using. If you are using Maven (M2Eclipse) you could download the sources. This might solve the problem.
Otherwise you could go and manually attach your sources. Here is how you manually attach sources.
Next you have to attach the sources-
Hope this helps
The "source not found" is a red herring - there may simply be no way to get access to the source that is throwing the error, because it is deep in the guts of the debugger's class loader.
The better question, then, is, "Why is scottrice.ChessPuzzles.ChessPuzzleDriver not being found?" The only possibility that occurs to me at the moment is that something might be weird in your debug configuration. Did you debug the program by just right-clicking a file with a main() and choosing "Debug As" -> "Java Application"?
Related
I am facing a problem, as the title suggests, have no idea what happened here. My eclipse does not show comments/docs in bubble any more. As you can see I have written some comments on a method but still it would not show them.
Note: I have restarted eclipse + PC several times without any success. The comments do not even appear for my own methods.
Please help
IDE's can be very moody sometimes. Try either completely restarting eclipse or restarting your machine all together. If all else fails, reinstall.
Eclipse may not showing code docs in different situations -
The code may have not java doc
Or the jar file for the code is not added in eclipse classpath
Today I came to work, happy. But when I opened my Eclipse, I saw that one of my projects has errors.It's weird because it shows that it has errors only in the window bar, and not in the Navigator. I don't have any Java errors, this is a valid project that was fine all the time:
Some of the errors on the error log of Eclipse:
JavaBuilder handling ImageBuilderInternalException while building: SP_Procedure
Cannot connect to VM
File <SomeFile> has been skipped, problem while reading ('Resource is out of sync with the file system')
Unhandled event loop exception
Internal error
When I run an application from this project, I get a warning message but when I proceed, it works fine, but still. It's very disturbing and I'm not sure if it's harmless.
I tried to:
Restart Eclipse
Restart my machine
Clean projects and recompiling them.
Refresh projects
Pray
Nothing helped. What could be the problem? (I'm using Indigo Service Release 2)
The following nuclear option has desperation written all over it. But I have been where the OP has been with the Juno version of Eclipse.
Run a "Synchronize with Repository" and save all of your local updates to a different directory.
Delete the project. (Check the box to delete the contents on disk. Scary step, but that's OK, because you saved it in a different directory in the previous step, right?)
Read in a fresh project from the repository. It builds happily at this point.
Integrate your local updates.
Keep on praying.
Looks that one unused JAR was deleted, but for some reason, I didn't get errors in any file, even in the files that imports this JAR! So what I did was restoring this JAR, delete unused imports and deleted the JAR again.
I've found this error after two days of navigating on this project on each file.. This is weird that Eclipse didn't recognize that1 this is an error, and throw many unrelated errors such as:
Cannot connect to VM
File has been skipped, problem while reading ('Resource is out of sync with the file system')
Unhandled event loop exception
Is this a bug in Eclipse? (All errors and warnings are enabled!)
1 As seen in the image in the question..
A class from the list of imports for the file seems to have moved out or the jar file containing the class is missing.
Expand the imports section and check if you find some classes that are missing but have been imported.
Though it is a pain, sometimes the easiest solution is to back up all your projects (either in a repository or somewhere else on your computer) then uninstall and reinstall eclipse. No it's not fun, but it should reset eclipse so everything works again. The downfall though is that you have to reconfigure eclipse to any special settings you had/reinatall any extra functionality currently installed (eg. android add-on) and reconnect to any repositories you have. While punting isn't fun, it can be effective... I hope you don't have to resort to this though.
I have went through that problem a lot of times, and tried everything you tried. Rebuild, recompile, refresh, remove and add JDK, remove and reinstall Eclipse... nothing worked
The only thing I concluded is that the workspace metadata was corrupted.
What I did (every time it happened) was
Create an empty workspace
Import -> existing projects into worskpace
Mark the "copy projects" (else it will only link them)
Wait for the copy, and start working with the new workspace
If you work with SCM systems (Git, SVN, etc), making a full checkout will do the trick too, but the worskpace import will let you retrieve those changes you didn't get to commit (if any).
It's a little painful if you have somethings already set (like JDK names, servers, etc), but then I realized it was faster than keep searching how to fix the workspace
Regards!
PS : I've been working with Kepler lately, and everything works fine till now
Click Window -> Show View -> Other -> General -> Problems
This view will show you what is wrong.
Did you, by any chance, update your virtual machine outside of Eclipse? I can't help but feel that we're both missing a finer detail here. I just keep seeing "cannot connect to VM" and thinking that it's a major clue.
Have you tried running anything from the terminal? Does it work there?
If so, do you know where your current edition of Java is located? Is Eclipse looking somewhere else?
Is this exclusive to one project? Do you use any additional libraries to the JDK?
Maybe try this for Resource is out of sync with the file system error:
Right click project in Eclipse Package Explorer
Close Project.
Right click project in Eclipse Package Explorer
Open Project.
Other things not mentioned:
project properties > java build path, see if any of those tabs got changed, local file got moved? read/write permissions on some file you are linking to?
project properties > java compiler, see if workplace settings have changed? maybe under errors/warnings, you can systematically set them to 'ignore' until the error goes away to determine what type of error it is?
maybe update some of the eclipse plugins?
I saw something like this happening for a number of reasons. Mainly because of validation in files other Java source code. See if you are validating XML for instance.
Right click your project and chose Properties (Alt+Enter) and Validation to see the related configuration.
As for the danger, I lived with those marks for ages and nothing wrong ever happened.
I've installed Eclipse and tried to do the "Hello World" program a couple of times and for some reason it never seems to work, could anyone help me out with this because I'm quite lost seeing as I've never used Eclipse before, heres a screenshot of my UI and what I get as an error:
Also I may have forgotten something very basic knowing me, seeing as it's been months since I last programmed, feel free to mention it nonetheless.
You are trying to run a program full of compiler errors, so no wonder it doesn't work. In your case it's the JRE configuration—you need to bind your installed JRE to the Eclipse's JRE setup. You can type Ctrl-3, jre, enter and you'll be able to go directly to the proper preference page.
Eclipse is not able to find HelloWorld.class file. Might be due to compile time problems.
You can check in the output directory of your project, weather .class file is there or not.
I'm trying to help another developer who is using Netbeans. When he runs or debugs some code of his in Netbeans (6.9.1) he gets an "Uncompilable source code" RuntimeException. I'm pretty experienced in Java but am more used to IntelliJ, and haven't used Netbeans at all.
I've done it a bit of googling and it seems Netbeans will compile code even with errors, and then throw the RuntimeException at the errors. (Fairly bad behaviour IMO, but I guess some will find it useful.) I've got him to completely rebuild the project with no compile errors, but the RuntimeException seems to still occur. I assume he's got some bad cached class data somewhere deep within Netbeans.
2 questions:
What is the best way to clear the cache so we can find out where the uncompilable code is?
Is there any way of turning off this behaviour so the code won't run/debug unless everything will compile, so these RuntimeException's won't be injected into the code?
I've googled a fair bit, but haven't found the answer to either of these questions yet.
Update: More information:
Turning off the "compile on save" option makes the problem go away. Turning CoS back on again brings the exception back. Unfortunately this isn't a fix, as CoS is a very useful option.
http://netbeans.org/bugzilla/show_bug.cgi?id=182009 seems the closest bug report, but it has been closed as "RESOLVED INCOMPLETE". Unfortunately the bug is hard to reproduce - the exception is happening in Java library code, when it calls a third-party library, so there isn't anything at the point the exception is thrown we can change. And the code will work for weeks, and then suddenly start throwing this error with no obvious reason why.
We've tried manually deleting the entire build directory - still not a fix.
We finally got a solution, but still don't quite know why the situation occurs. When you have Compile On Save activated, Netbeans generates a second set of class files for debugging etc. These are stored in $USER/.netbeans/var/cache/index/s*/java/*/classes
Somehow (not sure how) this directory can get corrupted or fail to update.
If you close netbeans, delete $USER/.netbeans/var/cache/index and all subdirectories and restart netbeans this clears the cache. If you have no compile errors, your problem ought to go away at this point.
NB: $USER is your user directory - on Windows 7 this is usually c:\Users\username, I guess on Unix it will be ~username.
If you get this problem please vote for, comment on, or add information to: http://netbeans.org/bugzilla/show_bug.cgi?id=182009
I experienced the same wired problem in NB 7.0.1, my hammer-IQ solution was to make a typo in the source code, run NB with this error (despite an error message) and than the cached class was successfully deleted.
I experienced this issue on Linux Mint Nadia with Netbeans 7.2.1, but was stumped as to where the cache location might be - mine was actually located at
/home/USER/.cache/netbeans/7.2.1
rather than in the .netbeans folder.
If you're not sure where the cache is located on your particular setup, just go to the help > about menu in Netbeans and it'll tell you the correct path.
After realising that the cause was a bad cache from the other posted solutions, I solved this problem by copying the file to another directory, deleting it from NetBeans, and then adding it again.
In fact, you neednt delete whole of index folder.
When you open netbeans and your project folder is active. Netbeans starts scanning files and creates temporary project folders (in index folder) for all active projects. If you check index\segments file(its a text file and can be viewed in notepad/(text editor)), you will be able to identify the folders that represent your project. You can then delete those folders and restart netbeans.
*Active project means those projects that were open before Netbeans was shutdown.
Had the same problem on Windows 7 with Netbeans 12.
Cache is here:
C:\Users\<Username>\AppData\Local\NetBeans\Cache
, but the deleting cache is not helpful sometimes. The better solution is to recompile the problematic class i.e. make a minor change (e.g. add space) and save.
Everything was going well. Nightly builds ran for more than a month with no problems. However, suddenly when invoking the feature builder from Eclipse the execution ends right away with the message.
ERRORLEVEL 13
As far as I know I haven't changed anything, as this computer is normally not touched. (It is only used for the nightly builds).
I've googled around to see what this error means but to no avail. I found a link from IBM that shows a custom bat file that catches this error, but the explanation given is not very useful.
My guess is that this is related to the workspace, somehow, or that the whole eclipse installation is corrupted.
Do you have any idea what this error means and how can it be corrected?
After reading what the error code means thanks to the answer from VonC I understood where to look. The problem was a lot more obscure that it seems.
I looked into the configuration folder for Eclipse (logs are either written there or in the .metadata folder when something goes wrong), and I found a huge log file. Inside the file I found the following error:
application org.eclipse.sdk not found
and the following exception, followed by a plugin name, several times:
java.util.zip.ZipException: Too many open files
Several plugins could not be loaded, causing a cascade of missing dependencies that prevented Eclipse from launching. I searched the web for this exception and found the following bug description from SUN, which says that Java 1.5.0 can not open more than 2,100 zip files.
The problem started a while after I installed the BABEL project translations for Eclipse into the build computer. These are more than 900 fragments, containing translations for many plugins, one for each language. As I installed it on top of an existing eclipse installation, it seemed that it was not a problem to open them.... until I cleared the workspace for the builds. Then Eclipse wouldn't launch anymore. I went over the limit. It didn't help that the first thing I tried to fix the build was, again.... clearing everything.
Because I only use this computer for headless builds, I didn't realize that the problem was in Eclipse itself and I was looking inside the build process. I only realized when I looked into the log file.
After installing Java 1.6.0_11 I was able to launch Eclipse and go on with my build.
It should mean "ant build failed", meaning the headless ant script fails at some point.
You should check if you can catch the log/output generated by this script to analyze this ant session and see at what point the ant script fails.
If it fails right away, it usually is because of:
a change in rights (writing access), or
in environment variable modifications, or
in resource access (path non accessible).
You also have to check if the computer is still in its original windows domain, and if the rights (admin ?) associated with the account running the ant script are still the same.