而不是arrayCollection

Question

我想從java返回值到Flex前端使用BlazeDs.Successfully Blazeds連接時檢索它顯示的值[對象Asynvtoken]沒有從java方法獲取值。

我的Flex代碼：

<fx:Script> 
     <![CDATA[ 
      import mx.collections.ArrayCollection; 
      import mx.controls.Alert; 
      import mx.rpc.AsyncToken; 
      import mx.rpc.events.FaultEvent; 
      import mx.rpc.events.ResultEvent; 

      public function get_user():void 
      { 
       var token:AsyncToken = ro.getOperation('getUser').send(); 
       user_grid.dataProvider = token.toString(); 
       Alert.show(user_grid.dataProvider.toString()); 
      } 
      private function fault(e:FaultEvent):void 
      { 
       Alert.show("code:\n" + e.fault.faultCode + "\n\nMessage:\n" + e.fault.faultString + "\n\nDetail:\n" + e.fault.faultDetail); 
      } 
      private function result(e:ResultEvent):void 
      { 
       userbtn.visible = false; 
       lnkbtn.visible = true; 
      } 
     ]]> 
    </fx:Script> 

    <fx:Declarations> 
     <!-- Place non-visual elements (e.g., services, value objects) here --> 
     <s:RemoteObject id="ro" 
         source="com.freelancer.GetUser" 
         fault="fault(event)" 
         destination="BlazeDsService"> 
      <s:method name="getUser" 
         result="result(event)"/> 
     </s:RemoteObject> 
    </fx:Declarations> 

     <mx:DataGrid id="user_grid" x="-1" y="-1" width="705" height="356"> 
      <mx:columns> 
       <mx:DataGridColumn headerText="Id" dataField="id"/> 
       <mx:DataGridColumn headerText="Name" dataField="name"/> 
       <mx:DataGridColumn headerText="Password" dataField="pwd"/> 
      </mx:columns> 
     </mx:DataGrid>  

    <s:Button x="322" y="429" id="userbtn" label="Get User" width="98" 
       height="23" cornerRadius="10" click="get_user()"/> 
    <mx:LinkButton x="331" y="429" id="lnkbtn" visible="false" label="Connected Please Wait Loading . . ."/> 

我的Java代碼：

public class GetUser 
{ 
    public static void main(String[] argv) 
    { 
     System.out.println("-------- PostgreSQL " + 
       "JDBC Connection Testing ----------"); 
     getUser(); 
    } 
    public static List<User> getUser() 
    { 
     List<User> ls=new ArrayList<User>(); 
     String host = "test"; 
      String port = "1234"; 
      String dbName = "test"; 
     Connection connection = null; 
     try 
     { 
      connection = DriverManager.getConnection(
        "jdbc:postgresql://" + host + ":" + port + "/" + dbName,"user", "user"); 

      System.out.println("Database is connected");  

     String strSQL = "select * from test"; 
     Statement st = connection.createStatement(); 
     ResultSet rs=st.executeQuery(strSQL); 
     System.out.println("hi,query executed"); 
     while(rs.next()) 
     { 
      User user = new User(); 
      user.setId(rs.getInt("id")); 
      user.setName(rs.getString("name")); 
      user.setPwd(rs.getString("pwd")); 
      ls.add(user); 
     } 
     } 
     catch(Exception e) 
     { 
      System.out.println(); 
     } 
     finally 
     { 
      try 
      { 
       connection.close(); 
      } 
      catch (Exception ignored) 
      { 

      } 
     } 
     return ls; 
    } 
} 

如果有人知道的解決方案，請幫助我。

Answer 1

請記住，對RPC服務的調用是異步的。

起初您撥打遠程功能getUser。這個請求被髮送到服務器，並且立即返回getOperation函數。此調用的結果是AsyncToken對象，它不是getUser調用的結果。該令牌是Asynchronous Completion Token design pattern的一部分。 RPC函數返回後，您的客戶端將會在您聲明的result函數的結果處理程序中獲得響應。結果是參數ResultEvent的一部分。

所以下面應該工作：

public function get_user():void 
    { 
     var token:AsyncToken = ro.getOperation('getUser').send(); 
    } 

    private function result(e:ResultEvent):void 
    { 
     user_grid.dataProvider = e.result;  
     userbtn.visible = false; 
     lnkbtn.visible = true; 
    }