package com.example.demo.config;

import com.example.demo.domain.Student;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.*;
import org.springframework.core.env.Environment;

@Configuration
@PropertySource("classpath:my.properties")
@Import(MyConfig2.class)
public class MyConfig {
    @Autowired
    private Environment environment;

    @Profile("dev")
    @Bean("student")
    public Student getStudent(){
        Student student = new Student();
        student.setAge(Integer.parseInt( environment.getProperty("age")));
        student.setName(environment.getProperty("name"));
        return student;
    }
}

其中，student这个bean只有指定了profile才会装配，比如在application.properties中：

spring.profiles.active=dev

@Profile注解不仅可以用在@Bean上，还可以用在注解类上，用在注解类时

package com.example.demo.config;

import com.example.demo.domain.Teacher;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Profile;

@Configuration
@Profile("dev2")
public class MyConfig2 {
    @Bean
    public Teacher getTeacher(){
        Teacher teacher = new Teacher();
        teacher.setName("david");
        teacher.setAge(32);
        return teacher;
    }
}

只有设定了profile为指定的值，该配置类中的所有bean才会装配