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java - ClassCastException 冒险

转载 作者:行者123 更新时间:2023-12-01 16:35:08 26 4
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我有 -

class A {
// contains certain set() and get() methods
}

class B extends A {
public A getAotherMethod() {
A a = new A();
// Contains some logic
return a
}
}

class C extends B {
// contains certain set() and get() methods
}

class D {
public Object getMethod() {

B b = new B();
// Contains some logic
return b.getAnotherMethod()
}
}


public static void main(String[] args) {
A a = new A();
B b = new B();
C c = new C();
D d = new D();
c = (C) d.getMethod(); // This is giving me ClassCastException
}

最佳答案

d.getMethod();

这将在内部调用b.getAnotherMethod(),其中有

A a = new A();
// Contains some logic
return a

A 类的对象无法转换为C 类

我们可以将子类对象分配给父类(super class)引用,但我们不能将父类(super class)对象分配给子类引用,什么是在这种情况下由您完成。

关于java - ClassCastException 冒险,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/10006106/

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