Spring如何通过注解引入外部资源(PropertySource Value)

<context:property-placeholder location="classpath*:spring.properties" file-encoding="utf-8"/>

<bean id="person" class="com.sff.app.bean.Person" scope="prototype">
    <property name="name" value="${person.name}"/>
    <property name="age" value="${person.age}"/>
</bean>

@Configuration
@PropertySource({"classpath:spring.properties"})
public class AppConfig4 {
    @Bean
    public Person person() {
        return new Person("kate", 12);
    }
}

person.nickName=aaa

import lombok.Data;
import org.springframework.beans.factory.annotation.Value;
@Data
public class Person {
    private String name;
    private Integer age;
    @Value("${person.nickName}")
    private String nickName;
    public Person() {
    }
    public Person(String name, Integer age) {
        this.name = name;
        this.age = age;
    }
}

@Test
public void testProperties() {
    AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(AppConfig4.class);
    Person person = ctx.getBean(Person.class);
    System.out.println(person);
}