Angularjs Grails在尝试更新列表中的项时出现“空指针异常”

我可以毫无问题地将项目添加到我的grails应用程序中，当我显示它们时，它如下所示：

[{"class":"server.Item","id":1,"assignedTo":"a","comments":null,
"completed":false,"creator":"a","name":"l","priority":"2","type":"Work"}]

def updateList() {
    def newItem = Item.findById(request.JSON.id)
    newItem.name = request.JSON.name
    newItem.type = request.JSON.type
    newItem.priority = request.JSON.priority
    newItem.completed = request.JSON.completed
    newItem.comments = request.JSON.comments
    newItem.creator = request.JSON.creator
    newItem.assignedTo = request.JSON.assignedTo
    newItem.save(flush: true)
    render newItem as JSON
}

只是一个JSON对象的列表，它工作得很好，在我的客户机中保持不变，等等

但是，当我尝试更新时，会出现空指针异常：

2015-05-26 11:56:33,504 [http-bio-8080-exec-10] ERROR errors.GrailsExceptionResolver  - 
NullPointerException occurred when processing request: 
[OPTIONS]     /server/todoList/updateList
Cannot set property 'name' on null object. Stacktrace follows:
Message: Cannot set property 'name' on null object

我的更新控制器如下所示：

[{"class":"server.Item","id":1,"assignedTo":"a","comments":null,
"completed":false,"creator":"a","name":"l","priority":"2","type":"Work"}]

def updateList() {
    def newItem = Item.findById(request.JSON.id)
    newItem.name = request.JSON.name
    newItem.type = request.JSON.type
    newItem.priority = request.JSON.priority
    newItem.completed = request.JSON.completed
    newItem.comments = request.JSON.comments
    newItem.creator = request.JSON.creator
    newItem.assignedTo = request.JSON.assignedTo
    newItem.save(flush: true)
    render newItem as JSON
}

它在我的角度控制器中被称为：

$scope.updateList = function() {
    angular.forEach($scope.items, function (item) {
       // serverList.save({command: 'updateList'}, item);
        $http.post('http://localhost:8080/server/todoList/updateList', item)
            .success(function(response) {})
            .error(function(response) {alert("Failed to update");});
    });
};

以下是我的项目的属性：

 name: $scope.thing,
 type: $scope.worktypeSelection,
 priority: $scope.prioritySelection,
 completed: false,
 comments: '',
 creator: $scope.username,
 assignedTo: $scope.assign.name

---

从angular调用时，项中是否有id？否，此处声明项：pastebin可能无法访问。向问题添加内容。您确定您按ID加载的项目确实在数据库中，因此不为空吗？我怀疑是分配newItem.name=request.JSON.name导致代码失败。如果我将Item与Item.list一起列出，则所有适当的项都在那里。