英文:
How to compare the derived objects from a base class in java?
问题
我有一个Base类，从Base类派生出两个类，分别是Derived1和Derived2，我想要检查object是否是Derived1或Derived2类型。
这是我的代码：
public class Base {
int ID;
}
public class Derived1 extends Base {
int subID;
}
public class Derived2 extends Base {
int subID;
}
public class Program() {
public static void main(String []args) {
Base object = new Derived1();
// 我想要检查"object"是否是Derived1或Derived2类型
}
}
英文:
I have a Base class and two classes are derived from the Base class namely Derived1 and Derived2, I want to check whether object is of type Derived1 or Derived2.
This is my code:
public class Base {
int ID;
}
public class Derived1 extends Base {
int subID;
}
public class Derived2 extends Base {
int subID;
}
public class Program(){
public static void main(String []args) {
Base object = new Derived1();
// I want to check whether "object" is of type Derived1 or Derived2
}
}
答案1
得分: 2
object.getClass() == Derived1.class会返回true。就像object instanceof Derived1一样。object.getClass().getName()会返回"com.foo.Derived1"。Derived1 = (Derived1) object;要么起作用，要么抛出ClassCastException。
这些是您的主要三种选择。
英文:
object.getClass() == Derived1.class would return true. As would object instanceof Derived1. object.getClass().getName() would return "com.foo.Derived1". Derived1 = (Derived1) object; would either work, or throw ClassCastException.
Those are your main 3 options.
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