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Java子类无法实现父类的抽象方法

[英]Java child class not able to implement parent class's abstract method

I have the following. 我有以下几点。 If I keep the @Override, I get an error that the method must implement or override a supertype method. 如果保留@Override,则会收到错误消息,指出该方法必须实现或重写超类型方法。 If I remove it, I get an error that the child class must implement the inherited abstract method. 如果删除它,则会收到一个错误,指出子类必须实现继承的抽象方法。 Why won't the below code work, and how can I make it do what I intend? 为什么下面的代码不起作用,如何使它达到预期目的?

BaseClass.java: BaseClass.java:

public abstract class BaseClass
{
    ...
    protected abstract <T extends Inputs> T doStuff(T inputs);

    public abstract static class Inputs
    {
        ...
    }
}

ChildClass.java: ChildClass.java:

public class ChildClass extends BaseClass
{
    ...
    @Override
    protected Inputs doStuff(Inputs inputs)
    {
        return inputs;
    }

    public static class Inputs extends BaseClass.Inputs
    {
        ...
    }
}

Try and: 尝试并:

public abstract class BaseClass<T extends BaseClass.Inputs>

and: 和:

public class ChildClass extends BaseClass<ChildClass.Inputs>

Which means you need to change doStuff() so that it returns T (in BaseClass ), without having a declared type variable: 这意味着您需要更改doStuff()以使其返回T(在BaseClass ),而无需声明类型变量:

public abstract T doStuff(T inputs);

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