The compiler for the JVM based programming language I am working in uses this code to run the specified method main

after compilation:

URL url = DyvilCompiler.config.outputDir.toURI().toURL();
Class c = Class.forName(mainType, false, new URLClassLoader(new URL[] { url }, ClassLoader.getSystemClassLoader()));
Method m = c.getMethod("main", String[].class);
m.invoke(null, new Object[] { args });

      

        
        
        
      

    

However, when compiling this code:

package dyvil.test
// some uninteresting import stuff
public class Main
{   
    @ArrayConvertible
    case class IntVector([int] ints = [ 1, 2 ])

    public static void main([String] args)
    {
        println(IntVector())
        println([ 1, 2, 3 ] as IntVector)
    }
}

      

        
        
        
      

    

Failure of the ClassLoader with an inner class (it is actually a nested class static

):

java.lang.ClassFormatError: Illegal class name "Ldyvil/test/Main$IntVector;" in class file dyvil/test/Main$IntVector
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:455)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:367)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at dyvil.test.Main.main(Unknown Source)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at dyvil.tools.compiler.util.TestThread.run(TestThread.java:32)

      

        
        
        
      

    

Note that the class files generated for Main dyvil/test/Main

and IntVector dyvil/test/Main$IntVector

define the internal relationship of the class:

Inner classes:
    [inner class info: #2 dyvil/test/Main$IntVector, outer class info: #7 dyvil/test/Main
     inner name: #9 IntVector, accessflags: 8 static]
  Enclosing Method: #7  #0 dyvil/test/Main

      

        
        
        
      

    

What's the problem with the signature Ldyvil/test/Main$IntVector;

?

Also, when adding the output directory to the classpath and changing the code to

Class c = Class.forName(mainType)

      

        
        
        
      

    

everything works without errors.

EDIT . This not only causes problems with the JVM, but when such a class is used in Eclipse, import

it terminates completely on completion.