!7

set flag AllPublic.

lib 1400554 // javassist

import javassist.bytecode.*;

p {
  ClassFile cf = new ClassFile(false, "User123", null);
  cf.setInterfaces(new S[] { className(IF1) });
  
  // add default constructor
  cf.addMethod(new MethodInfo(cf.getConstPool(), "<init>",
    Descriptor.ofConstructor(new CtClass[0])));
  
  byte[] bytes = bytesFromDataOutputStream(stream -> cf.write(stream));
  var cl = new InMemoryClassLoader(myClassLoader());
  Class<? extends IF1> c = cast cl.defineAClass("User123", bytes);
  print(c);
  
  IF1 f = newInstance(c);
  print(f);
}