Eclipse Failing to build classes - java

Eclipse has red cross for error on the project but there are no more red crosses on any files or anything in the project.
On running "build Project" there are no .class files created.
There does not seem to be any entries in the log file in workspace/.metadata. In fact, I deleted the log file and a new one has not been created.
I have tried Clean and clean all to no effect.
Any suggestions to look for where there might be a problem with this project ?
Thanks.

If you look in the 'problems' view you'll probably find an error message (this is normally displayed at the bottom, but if not go to : window -> show view -> problems.
Generally it's something like a build path error, or a JVM isn't correctly set.

Thanks...I had confused the Error log view with the Problem view and had not checked it. On looking at problem view, I see there is a dependancy problem.

Related

IntelliJ can't find classes in same package when compiling

As an extension to my previous question (IntelliJ can't find depencency when compiling, but can in editor.) which got solved, I now have a new issue which has sprung up.
Within the same packages, references to other classes are showing up with errors:
As you can see in the picture, there is happening at the line involving the BifCreatorController, even though that class is in the same package as the BifCreatorView.
Just like my previous question, I am failing to understand why IntellJ is spitting out those errors. This project works just fine in Eclipse, but I am looking to start moving away from eclipse.
Got same problem today. Rebuilding or restarting both didn't work for me. In the end, I tried to rename the class, problem solved! Then I rename the class to the name I want, everthing was fine!
This is because BifCreatorController is excluded from compilation (see the small "X" top-left icon near to the file name). One reason would be the file got some errors while compiling, IDEA proposed to exclude it from compilation and you had accepted.
Go to "File > Settings > Build, Execution, Deployment > Compiler > Excludes" and remove it from there.
I had the same problem, i cleared the cache and restarted but it did not solve the problem. Then i right clicked the not found class and selected Recompile and after recompilation the problem was solved.
For those who can't beat the trouble i suggest switching to maven because it's predictive:
Maven > Runner > Delegate IDE build/run actions to Maven
Another reason is the cache problem.
Go to -> File -> Invalidate Caches / Restart ...

Netbeans - Error: Could not find or load main class

So I'm making a java application in Neatbeans 7.4, been working at it for a while, everything was fine, running the project worked fine, but now when I hit run project, I get the error
Error: Could not find or load main class phleveledit.MainWindow
Java Result: 1
BUILD SUCCESSFUL (total time: 0 seconds)
I can't think of what I did right before this started happening, so I don't know what I should change.. The code doesn't appear to have any errors. Here's a screenshot of the IDE+project folder
Image (http://puu.sh/5ldYB) :
Any ideas?
Edit: Unfortunately I happened to fix this problem by removing some code, which probably had some errors Netbeans couldn't detect, but I don't know what was exactly wrong so can't vote on a correct answer.
Right click on your Project in the project explorer
Click on properties
Click on Run
Make sure your Main Class is the one you want to be the entry point. (Make sure to use the fully qualified name i.e. mypackage.MyClass)
Click OK.
Clean an build your project
Run Project :)
If you just want to run the file, right click on the class from the package explorer, and click Run File, or (Alt + R, F), or (Shift + F6)
Just close the Netbeans. Go to C:\Users\YOUR_PC_NAME\AppData\Local\Netbeans and delete the Cache folder. The open the Netbeans again and run the project.
It works like magic for me.
(AppData folder might be hidden probably, if so, you need to make it appear in Folder Options).
You can :
RightClick on project node and go to Set configuration
Select the main class for your application.
Then clean and build.
Even if the above steps don't work for you then then delete the Netbeans cache by deleting the (index) folder
User\.netbeans\SOME_NUMBER_reflecting_your_version\var\cache\index\
Sometimes due to out of memory space error, NetBeans does not load or find main class.
If you have tried setting the properties and still it is not working then try
Select the project from the project explorer
Click on Run in the Menu Bar
Click on Compile
It worked for me.
This condition happens to me every 6-months or so. I think it happens when closing NetBeans under very low memory conditions. I discovered that it could be easily corrected by (1) Rename your project, including its folder name using right-click on project explorer's project name---I put a simple suffix on the original name ("_damaged"). (2) Try BUILD. If that is successful, which it is for me, give three cheers. (3) Repeat step (1) to restore the original project name. BUILD and RUN should start without trouble.
I guess that the 'rename the project and folder' process causes a special rediscovery of the applications main location.
Try to rename the package name and the class/jframe names... The clean and build the application.
Right Click on the package name
Go to Refactor
Select Rename
Give it a meaningful name, preferably all in small letters
Click on Refactor
Do the same for the class/jframe names.
Last Select Run from Menu
7.Select Clean and build main project
That should do it!!! All best
I had the same issue once. The problem was not in the code. The cause was... renaming the project folder to some other non supporting name. My project name was "MobStick" and I renamed it to "MobStick - May 26, 2014 04:00PM". Renaming it back to normal solved my problem.
I have run into this error a couple of times as well and for me the above solutions did not work. What does seem to work is going to the Project Properties, and under Compiling toggling Compile on Save.
Using NetBeans 8.1, I got the dread
Error: Could not find or load main class
from carelessly leaving an empty line in the Project Properties > Run > VM Options field. Until you click in the field, you may not see the caret flashing out of place. Remove the empty line to restore equanimity.
I just ran into this problem. I was running my source from the command line and kept getting the same error. It turns out that I needed to remove the package name from my source code and then the command line compiler was happy.
The solutions above didn't work for me so maybe this will work for someone else with a similar problem.
I had the same problem, I had the package and class named the same. I renamed the class, then clean and build. Then I set the main class in the "run" under the properties of the project. I works now.
I found the following steps useful:
Right-click on the project in the left toolbar.
Hover over the 'Set Configuration' item.
Click on 'Customize...'
Click on 'Browse...' by the 'Main Class:' item.
Select the correct class.
Click 'Select Main Class'.
Click 'OK'.
My problem was that, apparently, my package name was being listed twice. Selecting the class using the dialog changed 'aclass.MainClass' to just 'MainClass'.
Hope this helps,
-HewwoCraziness
Edit: This is expanding on Mary Martinez's answer.
You can solve it in these steps
Right-click on the project in the left toolbar.
Click on properties.
Click on Run
Click the browse button on the right side.(select your main class)
Click ok
Possible Fixes:
Fix 1
Go to project properties (right click on the folder of your project in netbeans)
On left tab where it shows the categories, click on the "Run" selection
Then click on Browse to find the Main class you use on your project
Fix 2
Go to C:\Users\name\AppData\Local\Netbeans
delete the Cache folder.
Rebuild and Run
Fix 3
Download most recent version of Netbeans
Fix 4
Download most recent version of JDK and configure Netbeans to use that
I had the same problem for 3,4 days. On my PC my Jar file snapshot would give me this error while on my laptop it would work fine, I tried all the tricks shown above and on other forums like deleting cache, selecting main project file, etc, but somehow I was sure the reason it cannot find the main class when I would execute the JAR file was may be due to classpath issue in maven configuration, and I was right and I fixed it using following steps:
Right-click on the project, and go to the properties
Inside the properties go to Actions
On the right side in Actions select "Run Project" and you will see properties below
Inside "Set Properties" make sure exec.args=classpath %classpath "package_name"
In my case, the package name was accompanied by the main class. So my main class was Login while the package name was com.mycompany.islamic_center_app1, When I checked the entry was
com.mycompany.islamic_center_app1.Login
All I did was remove ".Login" from com.mycompany.islamic_center_app1 and it was fixed, no more errors.
close netbeans.
open netbeans again.
choose new project>>java application.
click next.
deselect create main class.
now make the application
clean build run
For more reference watch this video
try this it work out for me perfectly
go to project and right click on your java file at the right corner,
go to properties,
go to run,
go to browse, and then
select Main class.
now you can run your program again.
I had the same problem and I moved the project to a location where the path had no none-english letter and that fixed the problem
if you are on window os, then try to start NetBeans via administrative mode. right click on NetBeans icon and "Run as Administrative".
If none of the above works (Setting Main class, Clean and Build, deleting the cache) and you have a Maven project, try:
mvn clean install
on the command line.
Had the same problem here. Usually Clean and Build solves much of the problem. It happened to be caused by a wrongly installed plugin.
I faced the similar issue with Netbeans 10 and JDK 1.8.
I was not able to choose the right class to launch the project
When I compile or run the project, it shows me the Class name as "initializing view, please wait ...", I could not select the class name.
The issue was resolved with the NetBeans11.3, I am able to choose the correct Class file without any other changes, and the project is launched without any issues.
I had the same issue but none of this thread's solutions worked for me. Finally, it was OneDrive that caused the issue (for once more). So, I simply moved the NetBeansProjects folder from Documents which is synced with OneDrive, to C:\Users\yourName\AppData\Local\NetBeans (selected this path as there is already a NetBeans folder) and that was it, case closed.
If you also have NetBeansProjects to a OneDrive syncing folder it is worth trying this solution, just be sure that the path you will select is not synced with OneDrive. Also, remember to close Netbeans before making the folder change and after you move the folder to the new path you need just to open Netbeans again, go to file menu/open project and select your project from the new path.

Eclipse Project Error

I am working on the Bluetooth Chat from the Android Developer site in
Eclipse IDE. I am using Android 2.1 and changed the Action Bar to
display Toast messages instead and am only working with Secure
connections.
I have three classes under the same package called BluetoothChat,
BluetoothChatService, and DeviceListActivity and the project name is
BluetoothCh.
Two of the files had errors that I fixed. They were saved and are
clear of the red x that previously marked both .java files. All of
the other files are clear of errors as well. However, the main
Android project folder still contains a red x, and Eclipse is not
allowing a run or debug of the application because of errors in
the project.
Does anyone have any ideas how to solve this? Any advice is very much
appreciated! Thank you!
Refresh the project then clean the project.
Delete the error in the "Problems" tab.
Right click the project->Android->Clean project properties (or whatever it is).
Clean the project and rebuild it see if the X mark still persists.
"When I clean the project it now gives me errors that R cannot be resolved as a variable. Where should I go from here?"
It sounds like you have an error in your code somewhere. You need to find out where the error is (what file and line) and fix it. This can be done with the problems tab in eclipse. It should tell you the description, file, path, line, and type of error you are getting.

Cannot locate Error in eclipse project

I have a project that has a red x in explorer at the project level.
None of the source files have an error or a red x it only is at the very top level.
Where can I go to find more information about this error? I'm not seeing anything in the error log.
Open the Problems view (Window->Show View->Problems).
check your build path, some of the mentioned libraries may not be present at the specified locations.
or
refresh the project.
Window -> Show View -> General -> Problems should open up the view which lists all the problems. So you should be able to see the error and its description there.

Error: Unable to fnd class R.java No such file or dir

I keep getting this when trying to start a new project
ERROR: Unable to open class file C:\Users\Levi\Desktop\Android\workspace\Droid1\gen\com\androidbook\droid1\R.java: No such file or directory
I tried changing preferences to alter build path to project, but it still wouldnt work,,,
Is subfolder on desktop a bad place to install Eclipse?
Clean works sometimes and should be tried. I also find that blowing away the gen directory and refreshing will cause it be to rebuilt. Try that as well.
However, sometimes even that doesn't work and I've been forced to remove the project from Eclipse and then re-import it. This, unfortunately, works for me every time if the above has not.
Good luck.
Im also getting that error, running a Project->Clean in Eclipse helps for me.
Project->Clean should certainly fix this (unless your resources won't compile for some seperate reason).
I remember that the first time I ran Eclipse (in mid 2009, can't remember if it was Galileo or Ganymede or whatever) on Windows Vista, it presented several problems that were eventually traced to Eclipse itself being in a directory whose path contained a space...
Usually, the above tips (refresh, clean) work for me. But lately I had a very persistant instance of this error, which was caused by something else:
One of the layout .xml files in res/layout contained a reference to a custom view (org.company.project1.MyView). However, I had changed the package path (org.company.project2.MyView), so the reference had become invalid.
Thus, if everything fails try browsing your layout .xml files for invalid custom element definitions.
Cheers
after spending hours trying to ultimatly discover the issue behind the Class Issue not being found, resolved,or directory not there issue....
sometimes yes the issue is due to a bad binary or xml... as sometime a clean will do the trick or a xml edit will solve the day.. when all else fails.... this may do it..
"create a new workspace"
go into the workspace.... and then
Switch to your old workspace... in the newly formed workspace...
this was my silver bullet. so frustrating to not have a solid answer.
using Version: Helios Service Release 2
Build id: 20110218-0911

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