springboot项结构分析

向右看齐 2024-03-31 13:18 13阅读 0赞

### 三. SpringBoot 结构 ###

#### 3.1.SpringBoot 工作原理 ####

Spring boot应用程序采用各种Starters启动器,入口类是包含`@SpringBootApplication`注解和main方法的类,然后使用`@ComponentScan`注解自动扫描项目中的所有组件,并且Spring Boot会根据`@EnableAutoConfiguration`注解将项目中的依赖项自动配置到应用程序中.例如,如果MySQL数据库在类路径上,但尚未配置任何数据库连接,则Spring Boot会自动配置内存数据库.

#### 3.2 SpringBoot入口类 ####

Spring Boot应用程序的入口点是包含`@SpringBootApplication`注解的类,该类中包含运行Spring Boot应用程序的main方法.默认一般是一个\* application 结尾。

@SpringBootApplication注解包括自动配置,组件扫描和Spring Boot配置.  
如果将@SpringBootApplication注解添加到类中,则无需添加@EnableAutoConfiguration,@ComponentScan和@SpringBootConfiguration注解.@SpringBootApplication注解包括其他所有的注解.

#### 3.3 常见注解 ####

###### 1 @SpringBootApplication ######

@SpringBootApplication注解是Spring Boot的核心注解,用于标注程序是一个springboot 程序,它是一个组合注解,由多个注解组合而成

@Target(ElementType.TYPE)
    @Retention(RetentionPolicy.RUNTIME)
    @Documented
    @Inherited
    @SpringBootConfiguration
    @EnableAutoConfiguration
    @ComponentScan(excludeFilters = {
       
        
    		@Filter(type = FilterType.CUSTOM, classes = TypeExcludeFilter.class),
    		@Filter(type = FilterType.CUSTOM, classes = AutoConfigurationExcludeFilter.class) })
    public @interface SpringBootApplication {
       
        
      //此处忽略接口内部内容
    }

###### 2 @SpringBootConfiguration注解 ######

@SpringBootConfiguration注解可以用Java代码的形式实现spring中xml配置文件配置的效果。也就是用来加载配置文件。

@Target({
       
        ElementType.TYPE})
    @Retention(RetentionPolicy.RUNTIME)
    @Documented
    @Configuration
    public @interface SpringBootConfiguration {
       
        
    }

###### 3 @EnableAutoConfiguration注解 ######

启用自动配置，该注解会使Spring Boot根据项目中依赖的jar包自动配置项目的配置项,这也是 springboot 的核心注解之一,我们只需要将项目需要的依赖包导入进来,它会自动帮我们配置这个依赖需要的基本配置
    比如我们的项目引入了spring-boot-starter-web依赖,springboot 会自动帮我们配置 tomcat 和 springmvc

###### 4 @ComponentScan 注解 ######

默认扫描@SpringBootApplication类所在包的同级目录以及它的子目录。用来扫描组件和自动装配。

springboot 支持的自动配置可以查看到

在spring-boot-autoconfigure包中包含了支持的自动装配依赖,截图只是其中一部分,我们开发中常见的依赖都做了基本配置

![在这里插入图片描述][52ec4ee84d9d4caab3033e4444ae95af.png_pic_center]

![在这里插入图片描述][af46ee10ceb74e77a9b4add78f2850af.png_pic_center]

#### 3.4 Springboot 全局配置文件 ####

###### 1.格式 ######

SpringBoot使用的全局配置文件有两种格式：

• application.properties

• application.yml

虽然后缀不一样，但是项目中有一个就可以了，yml格式比properties格式的简洁一些。

这个文件的位置在配置文件放在src/main/resources目录或者类路径/config下。

properties 和 .yml，它们的区别主要是书写格式不同。
        1).properties
          server.port=8088
          server.servlet.context-path=/testboot
        2).yml
        server:
          port: 8088
          servlet：
            context-path: /testboot
        另外yml 格式不支持 @PropertySource 注解导入配置 
        :和值之间有一个空格

###### 2.作用 ######

全局配置文件的作用是：可以对一些默认配置值进行修改。

#### 3.5 starter 启动器 ####

springboot 提供了很多 starter, 可以帮我们快速构建相应的开发环境,导入相关的依赖,并设置相关配置

<table> 
 <thead> 
  <tr> 
   <th align="center">Name</th> 
   <th>Description</th> 
   <th>Pom</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td align="center"><code>spring-boot-starter</code></td> 
   <td>Core starter, including auto-configuration support, logging and YAML 核心启动器,包括自动配置,日志以及 YAML 支持</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-activemq</code></td> 
   <td>Starter for JMS messaging using Apache ActiveMQ 对Apache ActiveMQ提供支持</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-activemq/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-amqp</code></td> 
   <td>Starter for using Spring AMQP and Rabbit MQ 对Spring AMQP 和 Rabbit MQ支持</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-amqp/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-aop</code></td> 
   <td>Starter for aspect-oriented programming with Spring AOP and AspectJ 对 spring AOP和AspectJ提供支持</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-aop/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-artemis</code></td> 
   <td>Starter for JMS messaging using Apache Artemis 对Apache Artemis提供支持</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-artemis/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-batch</code></td> 
   <td>Starter for using Spring Batch</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-batch/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-cache</code></td> 
   <td>Starter for using Spring Framework’s caching support</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-cache/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-cloud-connectors</code></td> 
   <td>Starter for using Spring Cloud Connectors which simplifies connecting to services in cloud platforms like Cloud Foundry and Heroku</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-cloud-connectors/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-cassandra</code></td> 
   <td>Starter for using Cassandra distributed database and Spring Data Cassandra</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-cassandra/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-cassandra-reactive</code></td> 
   <td>Starter for using Cassandra distributed database and Spring Data Cassandra Reactive</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-cassandra-reactive/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-couchbase</code></td> 
   <td>Starter for using Couchbase document-oriented database and Spring Data Couchbase</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-couchbase/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-couchbase-reactive</code></td> 
   <td>Starter for using Couchbase document-oriented database and Spring Data Couchbase Reactive</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-couchbase-reactive/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-elasticsearch</code></td> 
   <td>Starter for using Elasticsearch search and analytics engine and Spring Data Elasticsearch</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-elasticsearch/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-jpa</code></td> 
   <td>Starter for using Spring Data JPA with Hibernate</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-jpa/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-ldap</code></td> 
   <td>Starter for using Spring Data LDAP</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-ldap/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-mongodb</code></td> 
   <td>Starter for using MongoDB document-oriented database and Spring Data MongoDB</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-mongodb/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-mongodb-reactive</code></td> 
   <td>Starter for using MongoDB document-oriented database and Spring Data MongoDB Reactive</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-mongodb-reactive/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-neo4j</code></td> 
   <td>Starter for using Neo4j graph database and Spring Data Neo4j</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-neo4j/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-redis</code></td> 
   <td>Starter for using Redis key-value data store with Spring Data Redis and the Lettuce client</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-redis/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-redis-reactive</code></td> 
   <td>Starter for using Redis key-value data store with Spring Data Redis reactive and the Lettuce client</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-redis-reactive/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-rest</code></td> 
   <td>Starter for exposing Spring Data repositories over REST using Spring Data REST</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-rest/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-data-solr</code></td> 
   <td>Starter for using the Apache Solr search platform with Spring Data Solr</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-data-solr/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-freemarker</code></td> 
   <td>Starter for building MVC web applications using FreeMarker views</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-freemarker/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-groovy-templates</code></td> 
   <td>Starter for building MVC web applications using Groovy Templates views</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-groovy-templates/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-hateoas</code></td> 
   <td>Starter for building hypermedia-based RESTful web application with Spring MVC and Spring HATEOAS</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-hateoas/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-integration</code></td> 
   <td>Starter for using Spring Integration</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-integration/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-jdbc</code></td> 
   <td>Starter for using JDBC with the Tomcat JDBC connection pool</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-jdbc/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-jersey</code></td> 
   <td>Starter for building RESTful web applications using JAX-RS and Jersey. An alternative to <a href="https://docs.spring.io/spring-boot/docs/current-SNAPSHOT/reference/htmlsingle/#spring-boot-starter-web" rel="nofollow"><code>spring-boot-starter-web</code></a></td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-jersey/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-jooq</code></td> 
   <td>Starter for using jOOQ to access SQL databases. An alternative to <a href="https://docs.spring.io/spring-boot/docs/current-SNAPSHOT/reference/htmlsingle/#spring-boot-starter-data-jpa" rel="nofollow"><code>spring-boot-starter-data-jpa</code></a> or <a href="https://docs.spring.io/spring-boot/docs/current-SNAPSHOT/reference/htmlsingle/#spring-boot-starter-jdbc" rel="nofollow"><code>spring-boot-starter-jdbc</code></a></td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-jooq/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-json</code></td> 
   <td>Starter for reading and writing json</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-json/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-jta-atomikos</code></td> 
   <td>Starter for JTA transactions using Atomikos</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-jta-atomikos/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-jta-bitronix</code></td> 
   <td>Starter for JTA transactions using Bitronix</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-jta-bitronix/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-jta-narayana</code></td> 
   <td>Spring Boot Narayana JTA Starter</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-jta-narayana/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-mail</code></td> 
   <td>Starter for using Java Mail and Spring Framework’s email sending support</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-mail/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-mustache</code></td> 
   <td>Starter for building web applications using Mustache views</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-mustache/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-quartz</code></td> 
   <td>Spring Boot Quartz Starter</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-quartz/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-security</code></td> 
   <td>Starter for using Spring Security</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-security/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-test</code></td> 
   <td>Starter for testing Spring Boot applications with libraries including JUnit, Hamcrest and Mockito</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-test/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-thymeleaf</code></td> 
   <td>Starter for building MVC web applications using Thymeleaf views</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-thymeleaf/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-validation</code></td> 
   <td>Starter for using Java Bean Validation with Hibernate Validator</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-validation/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-web</code></td> 
   <td>Starter for building web, including RESTful, applications using Spring MVC. Uses Tomcat as the default embedded container</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-web/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-web-services</code></td> 
   <td>Starter for using Spring Web Services</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-web-services/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-webflux</code></td> 
   <td>Starter for building WebFlux applications using Spring Framework’s Reactive Web support</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-webflux/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
  <tr> 
   <td align="center"><code>spring-boot-starter-websocket</code></td> 
   <td>Starter for building WebSocket applications using Spring Framework’s WebSocket support</td> 
   <td><a href="https://github.com/spring-projects/spring-boot/tree/master/spring-boot-project/spring-boot-starters/spring-boot-starter-websocket/pom.xml" rel="nofollow">Pom</a></td> 
  </tr> 
 </tbody> 
</table>

#### 附录 springboot 全局配置属性 ####

# ===================================================================
    # COMMON SPRING BOOT PROPERTIES
    #
    # This sample file is provided as a guideline. Do NOT copy it in its
    # entirety to your own application.               ^^^
    # ===================================================================
    
    
    # ----------------------------------------
    # CORE PROPERTIES
    # ----------------------------------------
    
    # BANNER
    banner.charset=UTF-8 # Banner file encoding.
    banner.location=classpath:banner.txt # Banner file location.
    banner.image.location=classpath:banner.gif # Banner image file location (jpg/png can also be used).
    banner.image.width= # Width of the banner image in chars (default 76)
    banner.image.height= # Height of the banner image in chars (default based on image height)
    banner.image.margin= # Left hand image margin in chars (default 2)
    banner.image.invert= # If images should be inverted for dark terminal themes (default false)
    
    # LOGGING
    logging.config= # Location of the logging configuration file. For instance `classpath:logback.xml` for Logback
    logging.exception-conversion-word=%wEx # Conversion word used when logging exceptions.
    logging.file= # Log file name. For instance `myapp.log`
    logging.level.*= # Log levels severity mapping. For instance `logging.level.org.springframework=DEBUG`
    logging.path= # Location of the log file. For instance `/var/log`
    logging.pattern.console= # Appender pattern for output to the console. Only supported with the default logback setup.
    logging.pattern.file= # Appender pattern for output to the file. Only supported with the default logback setup.
    logging.pattern.level= # Appender pattern for log level (default %5p). Only supported with the default logback setup.
    logging.register-shutdown-hook=false # Register a shutdown hook for the log

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