I've searched in previous posts but cant seem to find the solution, my code worked perfectly until i did something wrong , and now i get "Error: Could not find or load main class gaming.Game"
I think i might have deleted something in the eclipse configurations, How can i solve this?
Your title's error does not match the one you wrote in your question.
The "simon.Game" says that the Game class is in a package called simon. The other error you posted says that it's inside gaming package. This is important.
You can go into eclipse's run configuration and point to the correct class that has the main method.
With eclipse, it is sometimes necessary to remove a project and re-import it in order to solve problems like this. When removing the project, be sure not to leave "delete project contents on disk" checked.
Related
I have had this problem for years and years now where Eclipse would sometimes, seemingly for no reason, throw this error:
Error: Could not find or load main class [main-class] Caused by: java.lang.ClassNotFoundException: [main-class]
This error fires despite the class being in the file system and having previously worked with no flaws. Project clean does not fix it, and the filepath is completely valid. Consequent Google Searches usually turn up recommending that it's one of those two problems, or that you have to completely delete the project, or create a new workspace - so on.
I'm not sure what the exact cause of this problem is, and I haven't ever really been able to find one neither. However I had found a relatively simple fix for correcting it.
To fix this problem, what I've learned is that for some reason it tends to be Run Configuration itself. What you can do is:
Click "Run" in the toolbar
Click "Debug Configurations"
Create a new Run Configuration (However, don't just copy and paste the old one - for some reason this doesn't always fix the problem for me)
Set it up appropriately for the class, you can however copy the parameters from the old
Save and use that as the new run configuration for your program
This has generally fixed the problem for me most times. Hopefully someday Eclipse will have this properly fixed.
My current Eclipse version is 2021-12 (4.22.0)
I don't know if I did this self-answered question thing correctly, but for those of you who are banging your heads against your keyboard on Google right now trying to fix this, I hope this helps.
So I was making a java program in Netbeans IDE 8.2 and when I tried to run it, I got this error:
Error: Could not find or load main class helloworld.HelloWorld
C:\Users\name\AppData\Local\NetBeans\Cache\8.2\executor-snippets\run.xml:53: Java returned: 1
BUILD FAILED (total time: 1 second)
(Assume that helloworld is my project name and HelloWorld is my class name)
Everything was fine before, and I can't think of what I did that would cause this error to happen. This is the first time this error has happened to me so I don't know what to do. The code doesn't seem to have any errors.
Other projects of mine seemed to also have the exact same problem even though I haven't opened or edited them in weeks prior to this error occurring.
I tried many other ways but none of them seems to do the trick. Including deleting the cache folder and setting the main class through the properties tab.
Here's a screenshot of my code with the error, my name is crossed out:
Even if I type my code directly in the main class, which is class6homework.java, the error still occurs but it says class6homework.class6homework instead of the one in the screenshot.
Any ideas on how I could fix this?
UPDATE: I got it to work by moving the folder that contains the project to my desktop, didn't know why it wouldn't work in my original location. Thanks for the help.
Perhaps you don't have the main method included. If that is not the problem, try right clicking your class in the project tree and look for an option that says "Set as main class" or something like that
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 have a project in intellij and when I created my packages I made a mistake because they all start in capital letter, for example my previous package name was "Main" then I changed it to "main" and I did it to all of my packages.
error: package com.myproject.thesis.main does not exist import
com.myproject.thesis.main.Main;
but the "main" package and "Main" class does exist and already imported on the class that needs it. Also what should I name the package where I put my main class?
While it may not help in this case, a general thing to try when "My code compiles and runs, but IDEA is really confused about the symbols in my project" is to go into the "File" menu and choose "Invalidate Caches / Restart". I've rarely used it, and it doesn't always help, but every once in a while it fixes IDEA's confusion.
See also the IntelliJ IDEA help on Cleaning System Cache.
You need to edit configuration. From IntelliJ Run menu choose Edit Configurations. On the configuration window change the package name of Main class.
I hope this helps.
Try changing the packages to something else first. e.g. coma.myprojecta.thesisa.maina and get that to work. Then change it back to com.myproject.thesis.main. I think IntelliJ might be having problems with the change in case. If you change it something totally different and then back it IntelliJ should realise that things have changed.
As for what to call the class with main method, it is up to you. There is some good advice here. https://softwareengineering.stackexchange.com/questions/208062/naming-conventions-for-java-classes-that-have-a-static-main-method
You could also try a complete reset of the project. Create a whole new project, with the packages named (and cased) the way you want. Then, move the code files from your old project into the folders for your new project. IDEA should be able to see the files you put in there and parse them correctly.
Just clean the contents in /target (or "mvn clean"), and Intellij can find your new package correctly.
I am student currently trying to make a game in java. However I can't seem to run the project with the IDEA IDE. I am getting the message: "Exception in thread "main" java.lang.ClassNotFoundException: kamikaas.game.World" But when I look at the class structure I can't see why it wouldn't find the class. You can see the class structure and message here
It is probably an entry point issue. Make sure you set the entry point to your main class (the class with main method).
After you edit: As I guessed, your World class doesn't have a main method. You have to start your project with the correct class.
Ok, got a working project now, I added Maven to my project and it fixed my problem. As for the entry point suggestion, I have looked numerous times and it was correct. I don't know what the cause was but I don't care if it doesn't exist anymore.
I am new to Java and started with Eclipse Kepler Service Release 1. I started a small project that contains two classes, each in its own file:
MIDI_Wrap_Test - a main (program) class
MIDI_Wrap - another class (MIDI_Wrap) which is intended as a MIDI wrapper. -
Both classes are in the same directory with file names being the same as the class name (with .java added of course). Something goes wrong and I want to debug it. However, when control transfers from the main program to the MIDI_Wrap file/class I get the error message 'source not found'.
I found out that this is a quite common error. The question and answer that seem to mirror my problem perfectly is found here. I added the project to the debug source path, noticing that the correct directories were already added but to no avail.
I must be doing something wrong but am not able to find out what. Can someone help me out of this?
I solved by shutting down eclipse and reopened it. This solved me, and code can be debug with source code view.