Spring Boot自定义starter

1.先搭建工程

  1)创建一个Empty Project

  在空工程的基础上创建两个模块，分别对应starter和autoconfiger

starter工程创建一个普通的maven工程即可：

自动配置工程先创建一个标准的spring boot项目：

暂时不选择其他模块：

2.配置依赖

在starter工程的pom.xml文件中配置对autoconfig的依赖
starter/pom.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.hsun</groupId>
    <artifactId>starter</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <!--引入autoconfig的依赖-->
        <dependency>
            <groupId>com.hsun</groupId>
            <artifactId>autoconfig</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
    </dependencies>
</project>

autoconfig的pom文件如下配置：
autoconfig/pom.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.hsun</groupId>
    <artifactId>autoconfig</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>autoconfig</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.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>
    </properties>

    <dependencies>
        <!--每一个starter都需要依赖spring-boot-starter-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
    </dependencies>
    
</project>

3.代码编写

  1)属性配置

  HelloProerties.java

package com.hsun.autoconfig;

import org.springframework.boot.context.properties.ConfigurationProperties;

@ConfigurationProperties(prefix ="hello")
public class HelloProerties {

    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;
    }
}

  2)判断依据类（被自动配置业务类）

  HelloService.java

package com.hsun.autoconfig;

public class HelloService {

    HelloProerties helloProerties;

    public HelloProerties getHelloProerties() {
        return helloProerties;
    }

    public void setHelloProerties(HelloProerties helloProerties) {
        this.helloProerties = helloProerties;
    }

    public  String sayHello(String name){
        return helloProerties.getPrefix()+"-"+name +helloProerties.getSuffix();
    }
}

  3)自动配置类

  HelloServiceAutoConfigration.java

package com.hsun.autoconfig;

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
@EnableConfigurationProperties(HelloProerties.class)
public class HelloServiceAutoConfigration {

    @Autowired
   private HelloProerties helloProerties;

    @Bean
    public HelloService helloService(){
        HelloService helloService = new HelloService();
        helloService.setHelloProerties(helloProerties);
        return  helloService;
    }
}

完成以上操作一个自定义的spring-boot-starter基本上开发完成了，接下来你需要做的是，注册配置

4.注册配置

  要想自动配置生效，需要需要注册自动配置类，在src/main/resource 下新建META-INF/spring.factories文件，如下图：

在spring.factories文件中填写如下内容注册：

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
com.hsun.starter.HelloServiceAutoConfigration

若有多个自动配置，则用“，”隔开，此处的“\”是为了换行后还能读到属性。

5.使用自定义的starter

  写到此处，自定义starter已经开发完毕，此处我们来创建一个典型的Spring Boot的Web应用，来测试自定义starter的可用性（项目创建略）
1）在pom.xml文件中引入自定义starter依赖(当然在引入之前，需要先将其install到本地仓库)

<?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.hsun</groupId>
    <artifactId>hello-spring-boot-starter-test</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>hello-spring-boot-starter-test</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.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>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.hsun</groupId>
            <artifactId>starter</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

如下编写一个简单的Controller，来测试自定义的starter

测试结果如下：

以上源码托管：https://github.com/fankongqiumu/spring