SpEL 解析有效表达式，表达式中还有更多数据

SpEL（Spring Expression Language）：简介和用途

java
@Component
public class Person {
    @Value("#{systemProperties['user.name']}")
    private String name;
    
    @Value("#{T(java.lang.Math).random() * 100}")
    private int age;
    
    // 省略getter和setter方法
}
@Configuration
public class AppConfig {
    @Bean
    public Person person() {
        return new Person();
    }
}
public class Main {
    public static void main(String[] args) {
        ApplicationContext context = new AnnotationConfigApplicationContext(AppConfig.class);
        Person person = context.getBean(Person.class);
        
        System.out.println("姓名：" + person.getName());
        System.out.println("年龄：" + person.getAge());
    }
}