springboot自定义starter-蒲公英云

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

@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
@AutoConfiguerAfter   //指定自动配置类的顺序
@Bean     //给容器添加组件
@ConfigurationProperties 结合相关的xxxProperties类来绑定相关配置
@EnableConfigurationProperties//让xxxPropeties生效加入容器

3.模式

启动器只用来做依赖导入；

专门来编写一个自定配置模块；

启动器依赖自动配置，被人只需引入启动器（starter）命名：自定义启动器名-spring-boot-starter

4.分别新建两个maven项目，启动器为com.hbsi.stater 自动配置为com.hbsi.stater.autoConfigurer

(1)启动器（com.hbsi.stater ）模块导入依赖

<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.hbsi.springboot</groupId>
    <artifactId>hbsi-spring-boot-starter</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <!-- 启动器 -->
    <dependencies>
    <!--引入自动配置模块 -->
        <dependency>
            <groupId>com.hbsi.springboot</groupId>
            <artifactId>hbsi-spring-boot-starter-autoconfigurer</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
    </dependencies>
</project>

（2）自动配置模块（com.hbsi.stater.autoConfigurer）倒入依赖

<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.hbsi.springboot</groupId>
    <artifactId>hbsi-spring-boot-starter-autoconfigurer</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.4.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
    <!-- 引入spring-boot0-starter;所有starter基本的配置 -->
     <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
     </dependency>
    </dependencies>
</project>

（3）新建HelloProperties.class,HelloService.class ,HelloServiceAutoConfiguration

HelloProperties.class

package com.hbsi.starter;
import org.springframework.boot.context.properties.ConfigurationProperties;
@ConfigurationProperties(prefix = "com.hbsi")
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;
    }
}

HelloService.class

package com.hbsi.starter;
import org.springframework.beans.factory.annotation.Autowired;
public class HelloService {
    HelloProperties helloProperties;
    public HelloProperties getHelloProperties() {
        return helloProperties;
    }
    public void setHelloProperties(HelloProperties helloProperties) {
        this.helloProperties = helloProperties;
    }
    public  String sayHello(String name) {
        return helloProperties.getPrefix() + "-" + name +"-" + helloProperties.getSuffix();
    }
}

HelloServiceAutoConfiguration

package com.hbsi.starter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
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应用才能生效
@EnableConfigurationProperties(HelloProperties.class)//用@EnableConfigurationProperties
//注解使@ConfigurationProperties生效，并从IOC容器中获取bean
public class HelloServiceAutoConfiguration {
    @Autowired
    HelloProperties helloProperties; 
    @Bean
    public HelloService helloSerice() {
        HelloService helloService = new HelloService();
        helloService.setHelloProperties(helloProperties);
        return helloService;
    }
}

(4) 在类路径下新建/META-INF/spring.factories ，让自动配置类生效

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
com.hbsi.starter.HelloServiceAutoConfiguration

（5）将两个maven安装到仓库（install）

(6)在其他maven项目中引入自定义的stater，便可以使用

<!--引入自定义的starter-->
        <dependency>
            <groupId>com.hbsi.springboot</groupId>
            <artifactId>hbsi-spring-boot-starter-autoconfigurer</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>