code: @SuppressWarnings("unchecked")
     public static <T> Class<T> defineClass(String className, byte[] b, Class<?> neighbor, ClassLoader loader)
        throws Exception {
        Class<T> c = (Class<T>) DefineClassHelper.defineClass(className, b, 0, b.length, neighbor, loader, PROTECTION_DOMAIN);
        // Force static initializers to run.
        Class.forName(className, true, loader);
        return c;
     }
docs: Define a class in the provided class loader from the array of bytes. Inspired by cglib
  <code>ReflectUtils.defineClass</code>
  
  @param <T> type of the class returned
  @param className class name in the format <code>org.objenesis.MyClass</code>
  @param b bytes representing the class
  @param neighbor a class in the same package as the loaded class
  @param loader the class loader where the class will be loaded
  @return the newly loaded class
  @throws Exception whenever something goes wrong