public void writeClosure(ClosureExpression expression) {
    CompileStack compileStack = controller.getCompileStack();
    MethodVisitor mv = controller.getMethodVisitor();
    ClassNode classNode = controller.getClassNode();
    AsmClassGenerator acg = controller.getAcg();

    // generate closure as public class to make sure it can be properly invoked by classes of the
    // Groovy runtime without circumventing JVM access checks (see CachedMethod for example).
    ClassNode closureClass = getOrAddClosureClass(expression, ACC_PUBLIC);
    String closureClassinternalName = BytecodeHelper.getClassInternalName(closureClass);
    List constructors = closureClass.getDeclaredConstructors();
    ConstructorNode node = (ConstructorNode) constructors.get(0);

    Parameter[] localVariableParams = node.getParameters();

    mv.visitTypeInsn(NEW, closureClassinternalName);
    mv.visitInsn(DUP);
    if (controller.isStaticMethod() || compileStack.isInSpecialConstructorCall()) {
      (new ClassExpression(classNode)).visit(acg);
      (new ClassExpression(controller.getOutermostClass())).visit(acg);
    } else {
      mv.visitVarInsn(ALOAD, 0);
      controller.getOperandStack().push(ClassHelper.OBJECT_TYPE);
      loadThis();
    }

    // now let's load the various parameters we're passing
    // we start at index 2 because the first variable we pass
    // is the owner instance and at this point it is already
    // on the stack
    for (int i = 2; i < localVariableParams.length; i++) {
      Parameter param = localVariableParams[i];
      String name = param.getName();
      loadReference(name, controller);
      if (param.getNodeMetaData(ClosureWriter.UseExistingReference.class) == null) {
        param.setNodeMetaData(ClosureWriter.UseExistingReference.class, Boolean.TRUE);
      }
    }

    // we may need to pass in some other constructors
    // cv.visitMethodInsn(INVOKESPECIAL, innerClassinternalName, "<init>", prototype + ")V");
    mv.visitMethodInsn(
        INVOKESPECIAL,
        closureClassinternalName,
        "<init>",
        BytecodeHelper.getMethodDescriptor(ClassHelper.VOID_TYPE, localVariableParams),
        false);
    controller.getOperandStack().replace(ClassHelper.CLOSURE_TYPE, localVariableParams.length);
  }
  protected ClassNode createClosureClass(ClosureExpression expression, int mods) {
    ClassNode classNode = controller.getClassNode();
    ClassNode outerClass = controller.getOutermostClass();
    MethodNode methodNode = controller.getMethodNode();
    String name =
        classNode.getName()
            + "$"
            + controller
                .getContext()
                .getNextClosureInnerName(
                    outerClass, classNode, methodNode); // add a more informative name
    boolean staticMethodOrInStaticClass = controller.isStaticMethod() || classNode.isStaticClass();

    Parameter[] parameters = expression.getParameters();
    if (parameters == null) {
      parameters = Parameter.EMPTY_ARRAY;
    } else if (parameters.length == 0) {
      // let's create a default 'it' parameter
      Parameter it = new Parameter(ClassHelper.OBJECT_TYPE, "it", ConstantExpression.NULL);
      parameters = new Parameter[] {it};
      Variable ref = expression.getVariableScope().getDeclaredVariable("it");
      if (ref != null) it.setClosureSharedVariable(ref.isClosureSharedVariable());
    }

    Parameter[] localVariableParams = getClosureSharedVariables(expression);
    removeInitialValues(localVariableParams);

    InnerClassNode answer =
        new InnerClassNode(classNode, name, mods, ClassHelper.CLOSURE_TYPE.getPlainNodeReference());
    answer.setEnclosingMethod(controller.getMethodNode());
    answer.setSynthetic(true);
    answer.setUsingGenerics(outerClass.isUsingGenerics());
    answer.setSourcePosition(expression);

    if (staticMethodOrInStaticClass) {
      answer.setStaticClass(true);
    }
    if (controller.isInScriptBody()) {
      answer.setScriptBody(true);
    }
    MethodNode method =
        answer.addMethod(
            "doCall",
            ACC_PUBLIC,
            ClassHelper.OBJECT_TYPE,
            parameters,
            ClassNode.EMPTY_ARRAY,
            expression.getCode());
    method.setSourcePosition(expression);

    VariableScope varScope = expression.getVariableScope();
    if (varScope == null) {
      throw new RuntimeException(
          "Must have a VariableScope by now! for expression: " + expression + " class: " + name);
    } else {
      method.setVariableScope(varScope.copy());
    }
    if (parameters.length > 1
        || (parameters.length == 1
            && parameters[0].getType() != null
            && parameters[0].getType() != ClassHelper.OBJECT_TYPE
            && !ClassHelper.OBJECT_TYPE.equals(parameters[0].getType().getComponentType()))) {

      // let's add a typesafe call method
      MethodNode call =
          answer.addMethod(
              "call",
              ACC_PUBLIC,
              ClassHelper.OBJECT_TYPE,
              parameters,
              ClassNode.EMPTY_ARRAY,
              new ReturnStatement(
                  new MethodCallExpression(
                      VariableExpression.THIS_EXPRESSION,
                      "doCall",
                      new ArgumentListExpression(parameters))));
      call.setSourcePosition(expression);
    }

    // let's make the constructor
    BlockStatement block = new BlockStatement();
    // this block does not get a source position, because we don't
    // want this synthetic constructor to show up in corbertura reports
    VariableExpression outer = new VariableExpression("_outerInstance");
    outer.setSourcePosition(expression);
    block.getVariableScope().putReferencedLocalVariable(outer);
    VariableExpression thisObject = new VariableExpression("_thisObject");
    thisObject.setSourcePosition(expression);
    block.getVariableScope().putReferencedLocalVariable(thisObject);
    TupleExpression conArgs = new TupleExpression(outer, thisObject);
    block.addStatement(
        new ExpressionStatement(new ConstructorCallExpression(ClassNode.SUPER, conArgs)));

    // let's assign all the parameter fields from the outer context
    for (Parameter param : localVariableParams) {
      String paramName = param.getName();
      ClassNode type = param.getType();
      if (true) {
        VariableExpression initialValue = new VariableExpression(paramName);
        initialValue.setAccessedVariable(param);
        initialValue.setUseReferenceDirectly(true);
        ClassNode realType = type;
        type = ClassHelper.makeReference();
        param.setType(ClassHelper.makeReference());
        FieldNode paramField =
            answer.addField(paramName, ACC_PRIVATE | ACC_SYNTHETIC, type, initialValue);
        paramField.setOriginType(ClassHelper.getWrapper(param.getOriginType()));
        paramField.setHolder(true);
        String methodName = Verifier.capitalize(paramName);

        // let's add a getter & setter
        Expression fieldExp = new FieldExpression(paramField);
        answer.addMethod(
            "get" + methodName,
            ACC_PUBLIC,
            realType.getPlainNodeReference(),
            Parameter.EMPTY_ARRAY,
            ClassNode.EMPTY_ARRAY,
            new ReturnStatement(fieldExp));
      }
    }

    Parameter[] params = new Parameter[2 + localVariableParams.length];
    params[0] = new Parameter(ClassHelper.OBJECT_TYPE, "_outerInstance");
    params[1] = new Parameter(ClassHelper.OBJECT_TYPE, "_thisObject");
    System.arraycopy(localVariableParams, 0, params, 2, localVariableParams.length);

    ASTNode sn = answer.addConstructor(ACC_PUBLIC, params, ClassNode.EMPTY_ARRAY, block);
    sn.setSourcePosition(expression);

    correctAccessedVariable(answer, expression);

    return answer;
  }