Running in Eclipse is Not Able to Find the Class

Question

Trying to run my project in Eclipse, but it creates the following error:

Apr 11, 2014 8:02:17 AM net.minecraft.launchwrapper.LogWrapper log
INFO: Loading tweak class name cpw.mods.fml.common.launcher.FMLTweaker
Apr 11, 2014 8:02:21 AM net.minecraft.launchwrapper.LogWrapper log
SEVERE: Unable to launch
java.lang.ClassNotFoundException: cpw.mods.fml.common.launcher.FMLTweaker
      at java.net.URLClassLoader$1.run(Unknown Source)
      at java.net.URLClassLoader$1.run(Unknown Source)
      at java.security.AccessController.doPrivileged(Native Method)
      at java.net.URLClassLoader.findClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:102)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      at java.lang.ClassLoader.loadClass(Unknown Source)
      at java.lang.Class.forName0(Native Method)
      at java.lang.Class.forName(Unknown Source)
      at net.minecraft.launchwrapper.Launch.launch(Launch.java:94)
      at net.minecraft.launchwrapper.Launch.main(Launch.java:27)

But I have all of the files included in my project.

This is a very similar issue to this, but I tried the solution of refreshing the classpath and it didn't work.

Any suggestions?

If you're not sure that all the required packages are imported, hit Ctrl + Shift + O inside the class that raises this error, and import all the required packages and the compile the code again. — Mohsen Kamrani, Apr 11 '14 at 14:23
what are you exactly trying to do? The question lacks information. You get ClassNotFoundException in a lot of cases. You already had a running code in eclipse and suddenyl you got this error or you imported a project and then you couldn't run it. what kind of project is it? — Sambhav Sharma, Apr 11 '14 at 14:24
Actually you could also look into markers and look for java errors if you have any.. or maybe build path errors. — Sambhav Sharma, Apr 11 '14 at 14:25
Wow @mok I can't believe I did not know that shortcut :P Thanks for sharing — Gladhus, Apr 11 '14 at 14:31

score 1 · Answer 1 · answered Apr 11 '14 at 14:32

1

If you're not sure that all the required packages are imported, hit Ctrl + Shift + O inside the class that raises this error, and import all the required packages and the compile the code again.

answered Apr 11 '14 at 14:32

Mohsen Kamrani

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score 0 · Answer 2 · edited Apr 19 '22 at 12:25

This problem clearly specifies it lacks class files.

Steps to narrow done this problem :

Clicking - Ctrl+Shift+T

Paste the package name cpw.mods.fml.common.launcher.FMLTweaker, you should be able to figure out, which jar/source file hold this.

Go to Build Path->Configure Build Path ->Order and Export-> Arrange the folders according to the sequence they have to be loaded. (Sometimes if A expects B but B is loaded after A, causes this issue)
Try to import the packages using Ctrl + Shift + o, which automatically gives the suggestions to select from. Pick the right one.
This might be even happening because of the same name class conflicts.(Same Class Name used in multiples jars/source files). Import the right package one from it.

Running in Eclipse is Not Able to Find the Class

2 Answers2