Error: [ng:areq]

错误描述：Error: [ng:areq] http://errors.angularjs.org/1.4.8/ng/areq?p0=HelloCtrl&p1=not%20a%20function%2C%20got%20undefined

    at Error (native)
    at http://localhost:8080/web/rs/angular.min.js:1:503
    at qb (http://localhost:8080/web/rs/angular.min.js:1:8403)
    at Qa (http://localhost:8080/web/rs/angular.min.js:1:8490)
    at http://localhost:8080/web/rs/angular.min.js:1:38051
    at w (http://localhost:8080/web/rs/angular.min.js:1:27806)
    at D (http://localhost:8080/web/rs/angular.min.js:1:28162)
    at g (http://localhost:8080/web/rs/angular.min.js:1:25189)
    at g (http://localhost:8080/web/rs/angular.min.js:1:25206)

    at http://localhost:8080/web/rs/angular.min.js:1:24829

Angular出现这种错误的原因，是由于没有在页面中使用模块引入controller导致的，修改内容如下：

添加：ng-app='app',然后在js中添加如下代码：