正确使用Spring的ResolvableType来确定泛型类型

import org.springframework.core.ResolvableType;

public class GenericClass<T> {
    public void printGenericType() {
        ResolvableType resolvableType = ResolvableType.forClass(GenericClass.class, getClass());
        Class<T> genericType = (Class<T>) resolvableType.resolveGeneric(0);
        System.out.println("Generic type is: " + genericType.getName());
    }
}

public class Main {
    public static void main(String[] args) {
        GenericClass<String> instance = new GenericClass<String>() {};
        instance.printGenericType(); // 输出: Generic type is: java.lang.String
    }
}

ResolvableType resolvableType = ResolvableType.forInstance(instance);
Class<T> genericType = (Class<T>) resolvableType.resolveGeneric(0);

public class GenericClass<T> {
    public Class<T> getGenericType() {
        Type genericSuperclass = getClass().getGenericSuperclass();
        ParameterizedType parameterizedType = (ParameterizedType) genericSuperclass;
        return (Class<T>) parameterizedType.getActualTypeArguments()[0];
    }
}