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Spring Boot ????

1. @SpringBootApplication ??

@SpringBootApplication ????????????????????????

• @SpringBootConfiguration
• @EnableAutoConfiguration
• @ComponentScan

??????????????????????Spring Boot?????????????@SpringBootApplication ?????????????????

2. @SpringBootConfiguration ??

@SpringBootConfiguration????? @Configuration ?????????????????????? Spring IoC ???????Spring Boot????????????? Spring ?????????? IoC ????????? bean ???

Spring Config ???????

Spring IoC ?????????????

2. ?? JavaConfig ????

@Configuration
public class MyConfiguration {
    // bean ??
    @Bean
    public StudentService studentService() {
        return new StudentServiceImpl();
    }
}

bean ????????

3. ?? XML ??????
2. ?? JavaConfig ??????

@Configuration
public class MyConfiguration {
    @Bean
    public StudentService studentService() {
        return new StudentServiceImpl(studentDao());
    }
    @Bean
    public StudentDao studentDao() {
        return new StudentDaoImpl();
    }
}

????????????????????????? bean ????

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3. @EnableAutoConfiguration ??

??

@EnableAutoConfiguration ???? @Import ????????? bean ???? IoC ??????? SpringFactoriesLoader ????????????????

SpringFactoriesLoader ?

?????? META-INF/spring.factories ??????????????????

spring.autoconfigure.EnableAutoConfiguration=org.springframework.boot.autoconfigure.admin.SpringApplicationAdminJmxAutoConfiguration,
org.springframework.boot.autoconfigure.aop.AopAutoConfiguration,
...

???????Spring Boot ??????????????????????? IoC ????

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4. Spring Boot ????????

3. Spring Boot ??????????????? @SpringBootConfiguration???? @EnableAutoConfiguration?
4. ?????????? SpringFactoriesLoader ?????? META-INF/spring.factories ????????
5. ?????????????????????????????HttpEncodingAutoConfiguration ???? HTTP ?????
6. ????????????????????? Properties ?????? HttpEncodingAutoConfigurationProperties??????????????

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5. @ComponentScan ??

@ComponentScan ?????????????????? @Component?@Service?@Repository ???? bean ??????????@ComponentScan ???????????????

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???????Spring Boot ?????????? Spring ???????????????????????????