eclipse ganymede erroneous red underlining - eclipse

i'm finding suddenly that eclipse, in a java project, is underlining references to uses of other class uses ive created in the same package. for another reason i reinstalled it today and the red underlinings went away. about an hour later, they popped up again. all classes have the package membership declaration.
anyone seen this before?

My guess is that your compilation is bad for one reason or another. To remedy this I usually do the following in order until one works:
Do a project clean (this should force a compile)
Close and reopen the project.
Close and reopen Eclipse.
I hope this helps.

Related

eclipse option (luna) to turn quick fix back on

Not sure what i typed by accident, some key sequence, and a popup appeared/disappeared in luna eclipse editor. After that the quick fix stop popping up, which is kinda handy for imports and new classes. It Quick fix continues to work in other projects in same workspace, and in other work spaces. Been through the options, can't find one. Replaced luna, still no go. Looked throug project files, still don't see it.
Any ideas, other than create a new project?

Launching a Project in Eclipse

I am trying to run my projects in Eclipse, whenever I used to run any program a window appear and it shows that project is launching and building.
This never happened before. In fact, it was working very okay an hour before but now, even for old created project it showing this and not moving ahead.
Is this a general thing happened in eclipse as I haven't seen this before.
I want to get out of this to move ahead and to run the project.
The Launcher looks like this :
The progress Bar is also not moving ahead if it's building the project.
It's definitely normal to see; there's times I'll see it two or three times in a day. It shows up if the launching process is waiting on anything or is expected to take more than a couple seconds.
In your case, it seems to be stuck on "Building workspace," which happens when you open Eclipse. The more projects you have in Eclipse and the more sections of workspace you have (groups of tabs), the longer it takes to build your workspace. So I'm going to wager a guess that you tried to launch a project within the first minute or two of Eclipse being open. Am I right?
If that's the case, just wait a bit, and watch the lower right corner (where it says "Launching Clock" in your screenshot). When it shows it's stopped trying to do start-up tasks, you should be good to go.
If Eclsipse had been open for a while, then perhaps Eclipse is busy with other junk and calling it "Building workspace." Maybe it's having a hard time understanding what to do with one of your projects, so check for compiler errors. You can also try to "clean" your projects (Project -> Clean).
If that also fails...hmmm...I'm sure there's other options before you get to this point, but you might need to re-install Eclipse. I suppose there's a chance that in the deep dark corners of Eclipse, a file was corrupted, causing Eclipse to hang on a task that requires a missing/bad file. But before you go this far, make you get second or third opinions, because I might be missing some simpler cause of your Eclipse hanging than what I've listed already.
I found the solution.
I don't know what was the error and why it was displaying the Launcher window and stuck there. But, I forcefully stopped eclipse using Task Manager and then restarted it.
When restarted it took few minutes (more than usual time) and I was done with it. now it's working okay.
Re-installation of Eclipse also worked but i tried this before re-installing or upgrading.

Eclipse Scala plug-in: "illegal cyclic inheritance"

I just updated to the latest Scala-IDE version on Eclipse, and it's highlighting loads of spurious "illegal cyclic inheritance" errors in code I know to be OK (it was before, and it still compiles and runs OK).
Any way to fix this? If not, how do I roll back to the previous version? I don't see any options to roll back or download earlier versions on the Scala IDE website.
Thanks.
edit: Never mind, it spontaneously sorted itself out after about 10 minutes sitting there showing errors. Will leave question here in case else anyone gets this.
"Project -> Clean Project" always helps me when Scala-IDE is showing weird error messages.
Sometimes errors will show in the editor, but not in the package explorer. Things still appear to compile ok when that occurs.

eclipse libraries no longer working

i had put two libraries on the build path of my project, and then i closed eclipse for the night. when i re-opened eclipse, and opened the same workspace, the libraries "aren't working" in that eclipse isn't doing any of the helpful things it was previously doing, like underlining bad syntax with red squigglies, reporting things that didn't get imported, etc. anyone have an idea of what happened?
Maybe you have disabled "Project->Build Automatically"?
Try Project->Clean. Perhaps the perspective has changed, e.g. from one language to another so it isn'd doing any syntax highlighting

Eclipse: Refreshing known types in Java project

If you press Shift+Ctrl+T or choose "Navigate > Open Type..." you get the "Open Type" dialog for quickly navigating to a known class. When you start typing a name only the classes for which the name matches stay visible. That way you can find a class of which you know the name very quick without having to browse through the package explorer tree.
This has been working great for me up until this morning. All of a sudden for a couple of my projects I am only seeing some of the types that exist. Of course I tried the obvious steps of refreshing the projects, cleaning the projects, re-building the projects, rebuilding the projects externally, but all to no avail. It is a bit odd since the types are known in other places. If I add an import statement Eclipse does not complain that it doesn't know the type and I can Ctrl-Click through the types to get to their file. However, the type navigation knows nothing about them.
In the past when InteliJ used to do this to me I would go find its cache files and delete them forcing it to rebuild. Does Eclipse have something similar I might do (I'm an Eclipse newbie)? I am using Eclipse 3.4.2 and I have it configured to not delete files on a clean (because our actual build process puts files into the output directories that I don't want Eclipse mucking with).
Have you tried closing and reopening the project? Only types from open projects are held in memory, and the refresh occurs when you Shift+Ctrl+T for the first time on a newly opened project.
Edit to add: Ctrl+Shift+R also displays the types (along with everything else) but it also supports the Camel-case thing to find the Java types quickly.
Close eclipse and delete any .index files and the savedIndexNames.txt file in workspace/.metadata/.plugins/org.eclipse.jdt.core once eclipse is restarted it will rebuildl the entire index for Ctrl+T
try starting eclipse with the -clean flag, you can add this to your eclipse.ini which can be found in the same directory as you eclispe.exe, or if you start eclipse using a bat or shell script, add it as a startup argument, e.g. eclipse -clean.
The clean will tidy your workspace, and should force eclipse JDT to recalulate types. Ive had issue with .snap files (with seem to be created on dirty shutdowns) that seem to corrupt my workspace until I clean them up, not long ago eclipse lost the Object class!! made for some interesting errors!
I get problems like this often. I tried your solution, noticed it seemed to rebuild its search index, but I still couldn't find any of my classes. Then I took a look at the little green arrow on top right corner of that dialog, and noticed I had a working set selected which belonged to another project. I find it a little dumb that Eclipse doesn't warn you about this or anything, since this can be a very annoying little detail that one tends to forget (me at least ;-)).
Anyways, clicked on "Deselect Working Set" and bam I can find my classes again. Thought I'd add this here since others may make the same mistake.
This worked for me -
Select your project in Package Explorer
Press F5 or Right click and select Refresh
I used the "-clean" as first line in the eclipse.ini (version Juno) and worked like a charm.
I'v tried all the answers and I still had the issue. I then tried this:
I deleted the project (it's a maven project) and re-imported it. This time I made sure i check the "Add Project(s) to working set" checkbox. After that Eclipse was able to find the classes in that project.
The problem must have started because I didn't check this checkbox when i first imported this project.
By the way, I'm using Neon
(Warning: Shameless marketing ahead)
If you like this feature, you would love nWire. nWire allows, among other things, to quickly search not only for types, but for any possible Java element like method or field. It also uses a navigator view which is non-modal. After searching you can see the class associations in a very quick and easy way. Check out the video on our site.