/**
   * Parse the BSHBlock for for the class definition and generate the class using ClassGenerator.
   */
  public static Class generateClassImpl(
      String name,
      Modifiers modifiers,
      Class[] interfaces,
      Class superClass,
      BSHBlock block,
      boolean isInterface,
      CallStack callstack,
      Interpreter interpreter)
      throws EvalError {
    // Scripting classes currently requires accessibility
    // This can be eliminated with a bit more work.
    try {
      Capabilities.setAccessibility(true);
    } catch (Capabilities.Unavailable e) {
      throw new EvalError(
          "Defining classes currently requires reflective Accessibility.", block, callstack);
    }

    NameSpace enclosingNameSpace = callstack.top();
    String packageName = enclosingNameSpace.getPackage();
    String className =
        enclosingNameSpace.isClass ? (enclosingNameSpace.getName() + "$" + name) : name;
    String fqClassName = packageName == null ? className : packageName + "." + className;

    BshClassManager bcm = interpreter.getClassManager();
    // Race condition here...
    bcm.definingClass(fqClassName);

    // Create the class static namespace
    NameSpace classStaticNameSpace = new NameSpace(enclosingNameSpace, className);
    classStaticNameSpace.isClass = true;

    callstack.push(classStaticNameSpace);

    // Evaluate any inner class class definitions in the block
    // effectively recursively call this method for contained classes first
    block.evalBlock(callstack, interpreter, true /*override*/, ClassNodeFilter.CLASSCLASSES);

    // Generate the type for our class
    Variable[] variables = getDeclaredVariables(block, callstack, interpreter, packageName);
    DelayedEvalBshMethod[] methods = getDeclaredMethods(block, callstack, interpreter, packageName);

    ClassGeneratorUtil classGenerator =
        new ClassGeneratorUtil(
            modifiers,
            className,
            packageName,
            superClass,
            interfaces,
            variables,
            methods,
            classStaticNameSpace,
            isInterface);
    byte[] code = classGenerator.generateClass();

    // if debug, write out the class file to debugClasses directory
    if (DEBUG_DIR != null)
      try {
        FileOutputStream out = new FileOutputStream(DEBUG_DIR + '/' + className + ".class");
        out.write(code);
        out.close();
      } catch (IOException e) {
        throw new IllegalStateException(
            "cannot create file " + DEBUG_DIR + '/' + className + ".class", e);
      }

    // Define the new class in the classloader
    Class genClass = bcm.defineClass(fqClassName, code);

    // import the unq name into parent
    enclosingNameSpace.importClass(fqClassName.replace('$', '.'));

    try {
      classStaticNameSpace.setLocalVariable(
          ClassGeneratorUtil.BSHINIT, block, false /*strictJava*/);
    } catch (UtilEvalError e) {
      throw new InterpreterError("unable to init static: " + e);
    }

    // Give the static space its class static import
    // important to do this after all classes are defined
    classStaticNameSpace.setClassStatic(genClass);

    // evaluate the static portion of the block in the static space
    block.evalBlock(callstack, interpreter, true /*override*/, ClassNodeFilter.CLASSSTATIC);

    callstack.pop();

    if (!genClass.isInterface()) {
      // Set the static bsh This callback
      String bshStaticFieldName = ClassGeneratorUtil.BSHSTATIC + className;
      try {
        LHS lhs = Reflect.getLHSStaticField(genClass, bshStaticFieldName);
        lhs.assign(classStaticNameSpace.getThis(interpreter), false /*strict*/);
      } catch (Exception e) {
        throw new InterpreterError("Error in class gen setup: " + e);
      }
    }

    bcm.doneDefiningClass(fqClassName);
    return genClass;
  }
 // This could be static
 public void setInstanceNameSpaceParent(Object instance, String className, NameSpace parent) {
   This ithis = ClassGeneratorUtil.getClassInstanceThis(instance, className);
   ithis.getNameSpace().setParent(parent);
 }