为什么在Java中收到NoClassDefFoundError？

Question

I managed to successfully compile my code, but I'm not able to execute it. How do I fix this? scannerTesting is my package and ScannerTesting.java is my main file.

D:\\Java>javac Testing\\src\\scannerTesting\\ScannerTesting.java

D:\\Java>java Testing\\src\\scannerTesting\\ScannerTesting Exception in thread "main" java.lang.NoClassDefFoundError: Testing\\src\\scannerTesting\\ScannerTesting <wrong name: scannerTesting/ScannerTesting> . . .

Answer 1

java -cp ./Testing/src scannerTesting.ScannerTesting

When you run java , it looks for matching classes within its classpath. So what these arguments are doing is add your source folder to the classpath using -cp , and specify that the class that should be run is scannerTesting.ScannerTesting .

For more information, check out java cli tool documentation at Oracle

Answer 2

scannerTesting is your package name,right?

If so, I suggest you run command "java" under the workspace D:\\Java\\Testing\\src

java scannerTesting.ScannerTest