避免 isInstance 语句

Question

我如何重构这个例子来避免我需要在每种数据类型中检查 isInstance 的这种情况？有什么模式可以遵循吗？

public interface GenericData {}

public interface IntegerData extends GenericData{
    public Integer Data();
}

public interface StringData extends GenericData{
    public String Data();
}

public interface Client {
    public boolean LoadData(GenericData data);
}

public class IntegerClientImpl implements Client{
    public boolean LoadData(GenericData data){
        return IntegerData.class.isInstance(data);
    };
}

Answer 1

您可以使用泛型

public interface Client<Data extends GenericData> {
    public boolean LoadData(Data data);
}

public class IntegerClientImpl implements Client<IntegerData> {
    @Override
    public boolean LoadData(IntegerData data){
        // ...
    }
}

避免 isInstance 语句

Avoiding isInstance statement

java

design-patterns

isinstance