javac error: Class names are only accepted if annotation processing is explicitly requested

I get this error when I compile my java program:

error: Class names, 'EnumDevices', are only accepted if annotation 
processing is explicitly requested
1 error

Here is the java code (I'm running this on Ubuntu).

import jcuda.CUDA;    
import jcuda.driver.CUdevprop;    
import jcuda.driver.types.CUdevice;

public class EnumDevices {

  public static void main(String args[]) {
     CUDA cuda = new CUDA(true);    
        int count = cuda.getDeviceCount();

        System.out.println("Total number of devices: " + count);

        for (int i = 0; i < count; i++) {

          CUdevice dev = cuda.getDevice(i);
          String name = cuda.getDeviceName(dev);
          System.out.println("Name: " + name);
          int version[] = cuda.getDeviceComputeCapability(dev);

          System.out.println("Version: " + 
              String.format("%d.%d", version[0], version[1]));
          CUdevprop prop = cuda.getDeviceProperties(dev);
          System.out.println("Clock rate: " + prop.clockRate + " MHz");
          System.out.println("Threads per block: " + prop.maxThreadsPerBlock);
        }
    }
}

Here is the javac command:

javac -cp /home/manish.yadav/Desktop/JCuda-All-0.3.2-bin-linux-x86_64 EnumDevices

How do I compile this program?

Solution 1:

You at least need to add the .java extension to the file name in this line:

javac -cp /home/manish.yadav/Desktop/JCuda-All-0.3.2-bin-linux-x86_64 EnumDevices

From the official faq:

Class names, 'HelloWorldApp', are only accepted if annotation processing is explicitly requested

If you receive this error, you forgot to include the .java suffix when compiling the program. Remember, the command is javac HelloWorldApp.java not javac HelloWorldApp.

Also, in your second javac-example, (in which you actually included .java) you need to include the all required .jar-files needed for compilation.

Solution 2:

I was stumped by this too because I was including the .Java extension ... then I noticed the capital J.

This will also cause the "annotation processing" error:

javac myclass.Java 

Instead, it should be:

javac myclass.java 

Solution 3:

Using javac ClassName.java to compile the program, then use java ClassName to execute the compiled code. You can't mix javac with the ClassName only (without the java extension).