Spring Boot 配置文件

1. @ConfigurationProperties

1. 告诉SpringBoot将本类中的所有字段和配置文件中相关的属性进行绑定
2. 值prefix = "person"意为配置文件中person下面的所有属性与IOC容器中的person对象字段进行一一映射
3. 只有这个组件是容器中的组件(配置类加@Component)，才能容器提供的@ConfigurationProperties功能

Person类

@Component
@ConfigurationProperties(prefix = "person")
public class Person {
    private String name;
    private Integer age;
    private Date birthday;
    private Boolean manager;
    private List<Object> pets;
    private Map<String, Object> maps;
    private Car car;
}

1.1 yml配置

application.yml

person:
  name: 张三
  age: 22
  birthday: 1990/04/20
  manager: true
  pets:
    - dog
    - cat
  maps: {v1: k1,v2: k2}
  car:
    name: 法拉利
    price: 5000000

运行结果对象的json：

{"name":"张三","age":22,"birthday":640540800000,"manager":true,"pets":["dog","cat"],"maps":{"v1":"k1","v2":"k2"},"car":{"name":"法拉利","price":5000000.0}}

1.2 properties配置

application.properties

person.name=张三
person.age=22
person.birthday=1990/04/20
person.manager=false
person.pets=dog,cat
person.maps.k1=v1
person.maps.k2=v2
person.car.name=Porche
person.car.price=3000000

配置properties的编码，避免乱码

运行结果对象的json:

{"name":"张三","age":22,"birthday":640540800000,"manager":false,"pets":["dog","cat"],"maps":{"k1":"v1","k2":"v2"},"car":{"name":"Porche","price":3000000.0}}

---

2. @Value

    @Value("${person.name}")
    private String name;

	// SpEL方式注入
    @Value("#{person.age}")
    private Integer age;

• @Value获取值和@ConfigurationProperties获取值比较

	@ConfigurationProperties	@Value
功能	批量注入配置文件中的属性	一个个指定
松散绑定	支持	不支持
SpEL	不支持	支持
JSR303数据校验	支持	不支持
复杂类型封装	支持	不支持

• 松散绑定指的是不区分fileName、file_name、file-name这三类属性配置写法

• JSR303数据校验是@Validated结合一些其他注解做校验
  
  

• 配置文件yml还是properties他们都能获取到值；

• 如果说，我们只是在某个业务逻辑中需要获取一下配置文件中的某项值，使用@Value；

• 如果说，我们专门编写了一个JavaBean来和配置文件进行映射，我们就直接使用@ConfigurationProperties；

---

3. @PropertySource

将配置文件中配置的每一个属性的值，映射到这个组件中向数据库的properties等等
Person

// @ConfigurationProperties和@PropertySource是可以一起用的
@Component
@ConfigurationProperties(prefix = "person")
@PropertySource(value = "classpath:person.properties")
public class Person {
    private String name;
    private Integer age;
    private Date birthday;
    private Boolean manager;
    // 读取的是classpath:person.properties的配置
    @Value("${person.email}")
    private String email;
    private List<Object> pets;
    private Map<String, Object> maps;
    private Car car;
}

person.properties

[e-mail]

运行的json***结果：

{"name":"张三","age":22,"birthday":640540800000,"manager":true,"email":"[e-mail]","pets":["dog","cat"],"maps":{"v1":"k1","v2":"k2"},"car":{"name":"法拉利","price":5000000.0}}

---

4. @ImportResource

在类路径下这样配置是不生效的userService不会初始化到IOC容器中，因为Spring Boot诞生的目的就是消除配置，

但是你非让配置文件生效也可以这样做

// 这个注解使applicationContext.xml生效
@ImportResource("classpath:applicationContext.xml")
@SpringBootApplication
public class Application {

    public static void main(String[] args) {

        SpringApplication.run(Application.class, args);

    }

}

---

5. 定义和**指定profile

有这种场景就是测试环境和生产环境的application文件配置不一样，避免改来改去，可以定义Profile

5.1 定义application-dev.yml

server:
  port: 8080

person:
  name: 张三
  age: 22
  birthday: 1990/04/20
  manager: true
  pets:
    - dog
    - cat
  maps: {v1: k1,v2: k2}
  car:
    name: 法拉利
    price: 5000000

5.2 定义application-prod.yml

server:
  port: 8082

person:
  name: 李四
  age: 26
  birthday: 1991/04/20
  manager: false
  pets:
    - bird
    - cat
  maps: {v1: k1,v2: k2}
  car:
    name: BYD
    price: 50000

5.3 定义application.yml

spring:
  profiles:
    active: dev

dev测试结果：

{"name":"张三","age":22,"birthday":640540800000,"manager":true,"email":"[e-mail]","pets":["dog","cat"],"maps":{"v1":"k1","v2":"k2"},"car":{"name":"法拉利","price":5000000.0}}

spring:
  profiles:
    active: prod

prod测试结果：

{"name":"李四","age":26,"birthday":672076800000,"manager":false,"email":"[e-mail]","pets":["bird","cat"],"maps":{"v1":"k1","v2":"k2"},"car":{"name":"BYD","price":50000.0}}

5.4 properties定义Profile

properties定义Profile与yaml类似，在application.properties配置文件中指定 spring.profiles.active=dev

5.5 **指定profile其他方式

• 在配置文件中指定 spring.profiles.active=dev
• 命令行：java -jar Spring-Boot-Demo-0.0.1-SNAPSHOT.jar --spring.profiles.active=dev
• 虚拟机参数：-Dspring.profiles.active=dev

6. 配置文件加载位置

• –file:./config/ （项目路径下的config）

• –file:./ (项目根路径)

• –classpath:/config/ （类路径下的config）

• –classpath:/ （类的根路径）

优先级由高到底，高优先级的配置会覆盖低优先级的相同配置；

SpringBoot会从这四个位置全部加载主配置文件，进行互补配置；

启动参数spring.config.location指定applicaiton.yml

java -jar Spring-Boot-Demo-0.0.1-SNAPSHOT.jar --spring.config.location=F:/application.properties

7. 外部配置加载

SpringBoot也可以从以下位置加载配置； 优先级从高到低；高优先级的配置覆盖低优先级的配置，所有的配置会形成互补配置

• 1.命令行参数

java -jar Spring-Boot-Demo-0.0.1-SNAPSHOT.jar --server.port=8086  --server.context-path=/demo

	所有的配置都可以在命令行上进行指定
	多个配置用空格分开； --配置项=值

• 来自java:comp/env的JNDI属性

• Java系统属性（System.getProperties()）

• 操作系统环境变量

• RandomValuePropertySource配置的random.*属性值

由jar包外向jar包内进行寻找，优先加载带profile

• 6.jar包外部的application-{profile}.properties或application.yml(带spring.profile)配置文件

• 7.jar包内部的application-{profile}.properties或application.yml(带spring.profile)配置文件

再来加载不带profile

• 8.jar包外部的application.properties或application.yml(不带spring.profile)配置文件

• 9.jar包内部的application.properties或application.yml(不带spring.profile)配置文件

• [e-mail]注解类上的@PropertySource

• 11.通过SpringApplication.setDefaultProperties指定的默认属性

所有支持的配置加载来源 ：参考官方文档 --Externalized Configuration

8. 自动配置原理

配置文件能配置的属性参照 --Part X. Appendices

8.1 寻找代码入口：

1. SpringBoot启动的时候加载主配置类@SpringBootApplication，开启了自动配置功能 @EnableAutoConfiguration
   
2. 父类的方法AutoConfigurationImportSelector#selectImports()
   
3. 调用本类的this.getCandidateConfigurations()
   
4. SpringFactoriesLoader#loadFactoryNames()
   

• 扫描所有jar包类路径下 META-INF/spring.factories
• 把扫描到的这些文件的内容包装成Properties对象
• 从Properties中获取到EnableAutoConfiguration.class类（类名）对应的值，然后把他们添加在容器中
  

4. 所有EnableAutoConfiguration加入到了容器中的值

# Auto Configure
org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
org.springframework.boot.autoconfigure.admin.SpringApplicationAdminJmxAutoConfiguration,\
org.springframework.boot.autoconfigure.aop.AopAutoConfiguration,\
org.springframework.boot.autoconfigure.amqp.RabbitAutoConfiguration,\
org.springframework.boot.autoconfigure.batch.BatchAutoConfiguration,\
org.springframework.boot.autoconfigure.cache.CacheAutoConfiguration,\
org.springframework.boot.autoconfigure.cassandra.CassandraAutoConfiguration,\
org.springframework.boot.autoconfigure.cloud.CloudAutoConfiguration,\
org.springframework.boot.autoconfigure.context.ConfigurationPropertiesAutoConfiguration,\
org.springframework.boot.autoconfigure.context.MessageSourceAutoConfiguration,\
org.springframework.boot.autoconfigure.context.PropertyPlaceholderAutoConfiguration,\
org.springframework.boot.autoconfigure.couchbase.CouchbaseAutoConfiguration,\
org.springframework.boot.autoconfigure.dao.PersistenceExceptionTranslationAutoConfiguration,\
org.springframework.boot.autoconfigure.data.cassandra.CassandraDataAutoConfiguration,\
org.springframework.boot.autoconfigure.data.cassandra.CassandraRepositoriesAutoConfiguration,\
org.springframework.boot.autoconfigure.data.couchbase.CouchbaseDataAutoConfiguration,\
org.springframework.boot.autoconfigure.data.couchbase.CouchbaseRepositoriesAutoConfiguration,\
org.springframework.boot.autoconfigure.data.elasticsearch.ElasticsearchAutoConfiguration,\
org.springframework.boot.autoconfigure.data.elasticsearch.ElasticsearchDataAutoConfiguration,\
org.springframework.boot.autoconfigure.data.elasticsearch.ElasticsearchRepositoriesAutoConfiguration,\
org.springframework.boot.autoconfigure.data.jpa.JpaRepositoriesAutoConfiguration,\
org.springframework.boot.autoconfigure.data.ldap.LdapDataAutoConfiguration,\
org.springframework.boot.autoconfigure.data.ldap.LdapRepositoriesAutoConfiguration,\
org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration,\
org.springframework.boot.autoconfigure.data.mongo.MongoRepositoriesAutoConfiguration,\
org.springframework.boot.autoconfigure.data.neo4j.Neo4jDataAutoConfiguration,\
org.springframework.boot.autoconfigure.data.neo4j.Neo4jRepositoriesAutoConfiguration,\
org.springframework.boot.autoconfigure.data.solr.SolrRepositoriesAutoConfiguration,\
org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration,\
org.springframework.boot.autoconfigure.data.redis.RedisRepositoriesAutoConfiguration,\
org.springframework.boot.autoconfigure.data.rest.RepositoryRestMvcAutoConfiguration,\
org.springframework.boot.autoconfigure.data.web.SpringDataWebAutoConfiguration,\
org.springframework.boot.autoconfigure.elasticsearch.jest.JestAutoConfiguration,\
org.springframework.boot.autoconfigure.freemarker.FreeMarkerAutoConfiguration,\
org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration,\
org.springframework.boot.autoconfigure.h2.H2ConsoleAutoConfiguration,\
org.springframework.boot.autoconfigure.hateoas.HypermediaAutoConfiguration,\
org.springframework.boot.autoconfigure.hazelcast.HazelcastAutoConfiguration,\
org.springframework.boot.autoconfigure.hazelcast.HazelcastJpaDependencyAutoConfiguration,\
org.springframework.boot.autoconfigure.info.ProjectInfoAutoConfiguration,\
org.springframework.boot.autoconfigure.integration.IntegrationAutoConfiguration,\
org.springframework.boot.autoconfigure.jackson.JacksonAutoConfiguration,\
org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration,\
org.springframework.boot.autoconfigure.jdbc.JdbcTemplateAutoConfiguration,\
org.springframework.boot.autoconfigure.jdbc.JndiDataSourceAutoConfiguration,\
org.springframework.boot.autoconfigure.jdbc.XADataSourceAutoConfiguration,\
org.springframework.boot.autoconfigure.jdbc.DataSourceTransactionManagerAutoConfiguration,\
org.springframework.boot.autoconfigure.jms.JmsAutoConfiguration,\
org.springframework.boot.autoconfigure.jmx.JmxAutoConfiguration,\
org.springframework.boot.autoconfigure.jms.JndiConnectionFactoryAutoConfiguration,\
org.springframework.boot.autoconfigure.jms.activemq.ActiveMQAutoConfiguration,\
org.springframework.boot.autoconfigure.jms.artemis.ArtemisAutoConfiguration,\
org.springframework.boot.autoconfigure.flyway.FlywayAutoConfiguration,\
org.springframework.boot.autoconfigure.groovy.template.GroovyTemplateAutoConfiguration,\
org.springframework.boot.autoconfigure.jersey.JerseyAutoConfiguration,\
org.springframework.boot.autoconfigure.jooq.JooqAutoConfiguration,\
org.springframework.boot.autoconfigure.kafka.KafkaAutoConfiguration,\
org.springframework.boot.autoconfigure.ldap.embedded.EmbeddedLdapAutoConfiguration,\
org.springframework.boot.autoconfigure.ldap.LdapAutoConfiguration,\
org.springframework.boot.autoconfigure.liquibase.LiquibaseAutoConfiguration,\
org.springframework.boot.autoconfigure.mail.MailSenderAutoConfiguration,\
org.springframework.boot.autoconfigure.mail.MailSenderValidatorAutoConfiguration,\
org.springframework.boot.autoconfigure.mobile.DeviceResolverAutoConfiguration,\
org.springframework.boot.autoconfigure.mobile.DeviceDelegatingViewResolverAutoConfiguration,\
org.springframework.boot.autoconfigure.mobile.SitePreferenceAutoConfiguration,\
org.springframework.boot.autoconfigure.mongo.embedded.EmbeddedMongoAutoConfiguration,\
org.springframework.boot.autoconfigure.mongo.MongoAutoConfiguration,\
org.springframework.boot.autoconfigure.mustache.MustacheAutoConfiguration,\
org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration,\
org.springframework.boot.autoconfigure.reactor.ReactorAutoConfiguration,\
org.springframework.boot.autoconfigure.security.SecurityAutoConfiguration,\
org.springframework.boot.autoconfigure.security.SecurityFilterAutoConfiguration,\
org.springframework.boot.autoconfigure.security.FallbackWebSecurityAutoConfiguration,\
org.springframework.boot.autoconfigure.security.oauth2.OAuth2AutoConfiguration,\
org.springframework.boot.autoconfigure.sendgrid.SendGridAutoConfiguration,\
org.springframework.boot.autoconfigure.session.SessionAutoConfiguration,\
org.springframework.boot.autoconfigure.social.SocialWebAutoConfiguration,\
org.springframework.boot.autoconfigure.social.FacebookAutoConfiguration,\
org.springframework.boot.autoconfigure.social.LinkedInAutoConfiguration,\
org.springframework.boot.autoconfigure.social.TwitterAutoConfiguration,\
org.springframework.boot.autoconfigure.solr.SolrAutoConfiguration,\
org.springframework.boot.autoconfigure.thymeleaf.ThymeleafAutoConfiguration,\
org.springframework.boot.autoconfigure.transaction.TransactionAutoConfiguration,\
org.springframework.boot.autoconfigure.transaction.jta.JtaAutoConfiguration,\
org.springframework.boot.autoconfigure.validation.ValidationAutoConfiguration,\
org.springframework.boot.autoconfigure.web.DispatcherServletAutoConfiguration,\
org.springframework.boot.autoconfigure.web.EmbeddedServletContainerAutoConfiguration,\
org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration,\
org.springframework.boot.autoconfigure.web.HttpEncodingAutoConfiguration,\
org.springframework.boot.autoconfigure.web.HttpMessageConvertersAutoConfiguration,\
org.springframework.boot.autoconfigure.web.MultipartAutoConfiguration,\
org.springframework.boot.autoconfigure.web.ServerPropertiesAutoConfiguration,\
org.springframework.boot.autoconfigure.web.WebClientAutoConfiguration,\
org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration,\
org.springframework.boot.autoconfigure.websocket.WebSocketAutoConfiguration,\
org.springframework.boot.autoconfigure.websocket.WebSocketMessagingAutoConfiguration,\
org.springframework.boot.autoconfigure.webservices.WebServicesAutoConfiguration

每一个这样的 XxxAutoConfiguration类都是容器中的一个组件，都加入到容器中；用他们来做自动配置；

8.2 自动配置类的原理：

ServerPropertiesAutoConfiguration


所以我们配置server.port=8080,server.contextPath=/demo就封到这个Bean, 因为@ConfigurationProperties是松散绑定，server.contextPath可以写为server.context_path或server.context-path，但是spring推荐写为server.context-path。

9. 打印自动配置报告

我们怎么知道哪些自动配置类生效？我们可以通过启用 debug=true属性；来让控制台打印自动配置报告，这样我们就可以很方便的知道哪些自动配置类生效；
application.yml

debug: true

Positive matches:

Negative matches:

其他：

10. @Conditional派生注解

作用：必须是@Conditional指定的条件成立，才给容器中添加组件，配置里面的所有内容才生效；

@Conditional扩展注解	作用（判断是否满足当前指定条件）
@ConditionalOnJava	系统的java版本是否符合要求
@ConditionalOnBean	容器中存在指定Bean；
@ConditionalOnMissingBean	容器中不存在指定Bean；
@ConditionalOnExpression	满足SpEL表达式指定
@ConditionalOnClass	系统中有指定的类
@ConditionalOnMissingClass	系统中没有指定的类
@ConditionalOnSingleCandidate	容器中只有一个指定的Bean，或者这个Bean是首选Bean
@ConditionalOnProperty	系统中指定的属性是否有指定的值
@ConditionalOnResource	类路径下是否存在指定资源文件
@ConditionalOnWebApplication	当前是web环境
@ConditionalOnNotWebApplication	当前不是web环境
@ConditionalOnJndi	JNDI存在指定项

说明：以上所有示例类未给出setter/getter