自定义starter · SpringBoot入门

starter： 1、这个场景需要使用到的依赖是什么？ 2、如何编写自动配置 ```java @Configuration //指定这个类是一个配置类 @ConditionalOnXXX //在指定条件成立的情况下自动配置类生效 @AutoConfigureAfter //指定自动配置类的顺序 @Bean //给容器中添加组件 @ConfigurationPropertie结合相关xxxProperties类来绑定相关的配置 @EnableConfigurationProperties //让xxxProperties生效加入到容器中自动配置类要能加载将需要启动就加载的自动配置类，配置在META-INF/spring.factories org.springframework.boot.autoconfigure.EnableAutoConfiguration=\ org.springframework.boot.autoconfigure.admin.SpringApplicationAdminJmxAutoConfiguration,\ org.springframework.boot.autoconfigure.aop.AopAutoConfiguration,\ ``` 3、模式：启动器只用来做依赖导入；专门来写一个自动配置模块；启动器依赖自动配置；别人只需要引入启动器（starter） mybatis-spring-boot-starter；自定义启动器名-spring-boot-starter 步骤： 1）、启动器模块 ```xml <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.atguigu.starter</groupId> <artifactId>atguigu-spring-boot-starter</artifactId> <version>1.0-SNAPSHOT</version>  <dependencies>  <dependency> <groupId>com.atguigu.starter</groupId> <artifactId>atguigu-spring-boot-starter-autoconfigurer</artifactId> <version>0.0.1-SNAPSHOT</version> </dependency> </dependencies> </project> ``` 2）、自动配置模块 ```xml <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.atguigu.starter</groupId> <artifactId>atguigu-spring-boot-starter-autoconfigurer</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>atguigu-spring-boot-starter-autoconfigurer</name> <description>Demo project for Spring Boot</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.10.RELEASE</version> <relativePath/>  </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies>  <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> </dependencies> </project> ``` ```java package com.atguigu.starter; import org.springframework.boot.context.properties.ConfigurationProperties; @ConfigurationProperties(prefix = "atguigu.hello") public class HelloProperties { private String prefix; private String suffix; public String getPrefix() { return prefix; } public void setPrefix(String prefix) { this.prefix = prefix; } public String getSuffix() { return suffix; } public void setSuffix(String suffix) { this.suffix = suffix; } } ``` ```java package com.atguigu.starter; public class HelloService { HelloProperties helloProperties; public HelloProperties getHelloProperties() { return helloProperties; } public void setHelloProperties(HelloProperties helloProperties) { this.helloProperties = helloProperties; } public String sayHellAtguigu(String name){ return helloProperties.getPrefix()+"-" +name + helloProperties.getSuffix(); } } ``` ```java package com.atguigu.starter; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication; import org.springframework.boot.context.properties.EnableConfigurationProperties; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; @Configuration @ConditionalOnWebApplication //web应用才生效 @EnableConfigurationProperties(HelloProperties.class) public class HelloServiceAutoConfiguration { @Autowired HelloProperties helloProperties; @Bean public HelloService helloService(){ HelloService service = new HelloService(); service.setHelloProperties(helloProperties); return service; } } ```