兩個不同的對象

Question

發件人：

ObjectA A = new ObjectA(); 
ObjectB B = new ObjectB(); 
//Connection is created 
socket.writeObject(B); 

接收機：

//不知道如何找到哪個對象，我應該強制轉換的對象:(

有沒有辦法在同一個對象流發送兩個不同的對象？

-PK

Answer 1

使用instanceof

A a = new A(); 
B b = new B(); 
C c = new C(); 
//say obj is the object you read from your socket. 
if(a instanceof A){ 
     System.out.println("a is instance of A, obj can be cast as A"); 
     A remoteA = (A)obj; //wont throw classcast exception!! 
} 
if(b instanceof B){ 
     System.out.println("b is instance of B, obj can be cast as B"); 
     B remoteB = (B)obj; //wont throw classcast exception!! 
} 
if(c instanceof C){ 
     System.out.println("c is instance of C,obj can be cast as C"); 
     C remoteC = (C)obj; //wont throw classcast exception!! 
} 

這兩個對象都有關係嗎？一個人繼承了另一個人嗎？如果是這樣，你需要明確檢查。

說（父類） - >乙

B b = new B() 

b instanceof B所以和b instanceof A將爲真。所以你需要小心。首先檢查孩子班。