I am using Eclipse debugger mode and for some reason, when I type an expression into the Expression view, no corresponding value shows up. Even when I type in the name of valid variables that are populated (I know they're valid and populated because the code is working as expected and I can see their value in the Variable view and when I hover over them, just not in the Expressions view). I have tried restarting Eclipse, refreshing/rebuilding projects and nothing seems to work. It was working absolutely fine earlier in the day and then suddenly stopped working mid debug without any changes in settings. Does anyone know why this has happened and how to fix it? (Just to clarify, I am not trying to view the expressions of anything like a lambda function which I know cannot be evaluated in Expression view).
Edit:
I think it has something to do with the fact that when I am debugging, Eclipse now stops at breakpoint in a new instance of that class but with a hollowed out J for Java next to the file name.
Turns out that the issue was in fact related to the edit I made to the original question. The hollowed out J for the file icon meant that while debugging, I was using the file as a resource instead of an actual compiled file. This caused the problem and also meant that changes I made to the code did not reflect because they weren't compiled. To resolve this I ensured that the projects I was using had the right dependencies and versions of other projects that are being used then refreshed gradle and restarted the server. That ensured that the desired file is actually compiled and not just used as a resource file.
You can use Debıg Shell panel to show value of variable.
You can open this panel with Perspectives -> Debug Shell
Note: On older versions of eclipse, the name of this panel was Display.
I'm using Eclipse Eclipse IDE for Java Developers [Version: 2018-12 (4.10.0)
Build id: 20181214-0600] to develop a JavaFX project but I got some problems.
After a Java update, I've found several errors in my CSS files. Eclipse seems to think the CSS files are Java source code, as figured in the image below.
When I drag the mouse on a error, the description is "Syntax error on token 'Invalid character', interface expected" (because of # symbol)
I'm sure the code is correct because there are no errors before the latest java update to version 1.8.2.
Anyone can help me?
Most likely what happened here is what #Gianpio Benincasa said: You've created a new class, then in the file explorer you renamed it.
However, it's worth checking this one: Go to window/preferences, type 'associations' in the filter box to quickly nav to setting General>Editors>File Associations, and scroll through the file types list for *.css. Click on it, and check which editors are associated with it.
An eclipse with no particularly relevant plugins should only list 'Text Editor', and it should be marked as default. If you added plugins specifically for editing CSS, those will also be listed (and one of those is now probably default instead). Perhaps you or someone else went out of their way to add the java editor to this list somehow. If that is the case, simply make 'text editor' the default again (click it, click 'default'), then click on the java editor, and click 'remove'.
for eclipse that is a java class, in fact the icon has the "J". Probably when you created it you have created a new class and then have renamed it.
Create a new generic file instead a java class and copy the contents to the new file.
For create a generic file, rightclick and follow new-> other-> General-> files
Have a nice day
I have set the jdk compliance level to 1.7 and the JRE version I am using is also set to 1.7.
But I am getting a red cross on index.jsp. What could be the reason for this ?
Though I can see the file running in the browser, eclipse's console doesn't show any error.
First make sure there really are no errors: Window -> Show View -> Other... -> Markers.
If there are none, sometimes Eclipse gets stuck thinking there are errors when there aren't. Close all editors, clean the project, close then reopen it in the project explorer (right-click on it), and see if the error clears.
I've also noticed that Eclipse has weird issues parsing JSP; sometimes it's confused and you just have to ignore it, but you could try opening the JSP file, selecting all, cutting, then pasting to force a recheck (or sometimes cut -> clean build -> paste).
I don't know why it does this, and I've been reading / filing bug reports for literally years, but it really seems to choke on JSP (something about the mix of HTML, Java, and JSP tags doesn't sit right with its parser).
Eclipse marks with this sign any file containing syntax errors (not compiling). If you don't have any syntax errors, then you should try cleaning up all your projects, as sometimes it may look inside old metadata files to determine whether there are errors in a given file.
I have a Maven Java project, imported using m2eclipse.
The target/ directory is not marked as 'Derived' by m2eclipse.
Problems:
It is validated, so any validation error appear twice. My example shows a JSP Problem, when I insert intentionally an error in a jsp.
When I want to open a resource with Ctrl-Shift-R, all files appear twice, and I run the risk of editing the copy instead of the original file.
Possibly see post eclipse-ignore-folder
Note: When I set manually the directory to derived, the validation problem doesn't disappear, so that would only be part of the solution...
Question:
Is there something I need to do, so that m2eclipse sets the target/ directory to 'Derived' ?
Yeah, that has been around for a while. I wrote a plug-in that allows you to mark directories as "derived" without having to find them all (http://eclipsefrills.sourceforge.net/). It's not great, and you still have to manually run the action to make it work, but it may help.
Odd, though, I have not noticed the problem lately, myself. I wonder if there is some setting in the preferences that takes care of this now.
Good luck.
I got rid of this problem by writing a custom plug-in KeepTargetDerivedPlugin. As its name suggests, it automatically keeps all target folders derived (unlike the other solutions, which require user action).
Still, e. g. the YA2O's plug-in can be used to mark derived folders of projects which already reside in the given Eclipse workspace.
Yes: open a bug report :)
I have been so annoyed by this problem that I wrote a plugin to solve it. You can get the source and jar from here.
I've downloaded, unzipped and setup Eclipse 3.4.2 with some plugins (noteable, EPIC, Clearcase, QuantumDB, MisterQ).
Now I find when I'm editing Java projects the code completion is not working. If I type String. and press ctrl+space a popup shows "No Default Proposals" and the status bar at the bottom shows "No completions available".
Any ideas?
Try restoring the default options in 'Windows > Preferences > Java > Editor > Content Assist > Advanced'
An example of the kind of data you see in this preference screen, however not necessarily what you currently have.
(From Vadim in this blog post " Content Assist Duplicates in Eclipse (Mylyn)":
if have duplicate Mylyn entries, uncheck the duplicate entries that do not contain "(Mylyn)" in their name)
The Eclipse help page defines the default list to restore:
Select the proposal kinds contained in the 'default' content assist list:
Other Java Proposals,
SWT Template Proposals,
Template Proposals,
Type Proposals
I'm adding an answer here in case someone else finds this on Google. Same symptoms; different problem. For me, the type caches had become corrupt.
From http://mschrag.blogspot.co.nz/2009/01/open-type-cant-find-your-class.html
Quit Eclipse
Go to workspace/.metadata/.plugins/org.eclipse.jdt.core
Remove *.index and savedIndexNames.txt
Restart Eclipse and search Ctrl+T for the offending type. The indexes will be rebuilt.
In case someone comes here and want to activate the autocomplete function, go to
Preferences -> Java -> Editor -> Content Assist.
Then in the Auto Activation section fill in Auto activation triggers for Java:
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ._
For those running Xfce + having IBus plugin activated, there might be keyboard shortcut conflict.
See more info on my blog: http://peter-butkovic.blogspot.de/2013/05/keyboard-shortcut-ctrlspace-caught-in.html
UPDATE:
as suggested by #nhahtdh's comment, adding the some more info to answer directly: IBus plugin in Xfce uses by default Ctrl+Space shortcut for keyboard layout switching. To change it, go to: Options and change it to whatever else you prefer.
Check the lib of your project. It may be that you have include two such jar files in which same class is available or say one class in code can be refrenced in two jar files. In such case also eclipse stops assisting code as it is totally confused.
Better way to check this is go to the file where assist is not working and comment all imports there, than add imports one by one and check at each import if code-assist is working or not.You can easily find the class with duplicate refrences.
Another solution which worked for me is to go to Java--> Appearence --> Type Filters and do disable all
None of these worked for me.
I was experiencing this issue in only once particular class. What finally worked for me was to delete the offending class and recreate it. Problem solved... mystery not so much!
If you have installed Google Toolbar for IE, may be you can face the same problem. Because, the toolbar capture the shortcut ctrl+Space.
I had this problem and like #Marc, only on a particular class. I discovered that I needed to designate Open With = Java Editor. As a Eclipse newbie I hadn't even realized that I was just using a plain text editor.
In the package explorer, right-click the file and chose "Open With".
I faced this problem, and spent hours trying to figure out the issue. tried to follow the steps mentioned in the different answers above, the solution I found is on the same lines as Mona suggested, but slightly different. Tried to add as a comment to Mona's answer but no option was available.
Issue with my eclipse was, classpath somehow got corrupted and all the jars and dependent projects were missing. after taking the latest .classpath from repository it worked fine.
Check that you did not filter out many options inside the Window > Preferences > Java > Appearance > Type Filters
Items in this list will not be appear in quick fix, be autocompleted, or appear in other various places like the Open Type dialog.
I also face this issue but it is resolved in different way.
Steps that I follow may be helpful for others.
Right click on project (the one you are working on)
Go to Properties > Java Build Path > JRE System Library
Click Edit... on the right
Choose the JRE 7
Once you have you configuration checked and completion is still not working:
make sure you have the right directory structure.
Do you see the right icon beside the file?:
It will tell you how the file will be treated by Eclipse:
I am posting this answer as I had that story with with Maven webapp artifact. By default Maven-WebApp does not create folder for sources and I put my Java into resources, wondering for 5 minutes what was going on... :)
Running STS on Java Spring Boot projects, here's what works for me :
Maybe this helps other people who come across the same issue.
My setup: old Gradle project (version Gradle 2.12) made by someone else, imported using the Gradle Import Wizard into STS (Eclipse Oxygen.2 (4.7.2)).
Code completion did not work either (and I still have hollow Js at the Java files), but at least I got the code completion to work by doing:
right click on the project folder > Properties > Gradle > Configure Workspace Settings > Java > Editor > Content Assist > Advanced
check "Java Proposals in upper window.
2x Apply & Close
I have run into this problem since upgrading to Eclipse 2019-09. Based on some of the suggestions above, this is what worked for me.
I had to go to Eclipse -> Preferences -> Java -> Editor -> Content Assist -> Advanced.
I found out that if I turn on any of the key binding proposals, Java Non-Type, Java, Java (Task-Focused) or Java Type proposal, then I was able to use auto complete. If I turned them all on, then not only did auto complete work, but I got duplicate methods listed. I am guessing, but I will probably used Java Type Proposals. Any clarification of what differs for these four types would be appreciated.
In my case, Intellisense had only disappeared in a few classes in one project. It turned out this was because of a missing library on the build path (although it worked previously).
So definitely check all the errors or problems in Eclipse and try to find if a library may be missing
For those who use the latest 3-19 eclipse build:
It just happened to me when upgrading from Oxygen to 3-19 eclipse version, so I assume the auto-complete feature does not migrated correctly during the upgrade process.
The only solution that worked for me was to create a new eclipse workspace, and import the project/s to it. It might take a few minutes, but it worth it - comparing to the time spent on other solutions...
I ran into this and it ended up being I was opening the file with the text editor and not the java editor.
For me the issue was a conflict between several versions of the same library. The Eclipse assist was using an older version than maven.
I had to go to the .m2 directory and delete the unwanted lib version + restart eclipse.
I experience problems on Eclipse Neon when editing a file which does not belong to the project directory. When I copy the same file to the project root directory, not even to the src directory, the completion starts working.
When the file is opened from a different directory, only completion for JRE works. That is for example: java. completes, but junit. does not.
Just in case anyone got to a desperate point where nothing works... It happened to us that the content assist somehow shrunk so no suggestion was shown, just the "Press Ctrl+Space for non-Java..." could be seen.
So, it was just a matter of dragging the corner of the content assist to enlarge the pop-up.
I know, embarrassing. Hope it helps.
Note: this was an Ubuntu server with Xfce4 using Eclipse Oxygen.
If you're experiencing this in an enum, or when initializing an array with anonymous classes, it's a known bug in Eclipse. See Eclipse content assist not working in enum constant parameter list.
We can change the settings as per our requirement.
Suppose we want to make java proposal as highest priority we need to do changes as shown below.
Windows > Preferences > Java > Editor > Content Assist > Advanced
Choose Java proposal and click on up button
For me in Sep 2021 it was an odd Eclipse bug. I had a multi-line string inside an annotation in my Class. This caused just that particular class to fail when trying to code complete (even though the class compiled just fine).