编写自己的Spring Boot Starter

1.新建一个maven项目

命名规则统一是xxx-spring-boot-starter

完整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.22xcode</groupId>
    <artifactId>mystarter-spring-boot-starter</artifactId>
    <version>1.0</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.2.RELEASE</version>
    </parent>


    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-autoconfigure</artifactId>
        </dependency>
    </dependencies>

</project>

2.功能实现类

package com.test;

/**
 * 功能实现类
 */
public class GetHashCodeClass {

    private String target;

    public GetHashCodeClass(String target) {
        this.target = target;
    }

    public String getHashCode() {
        return String.valueOf(this.target.hashCode());
    }

}

3.配置读取类

package com.test;



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

/**
 * AutoConfigurationProperties
 *
 * @since 2020/06/29 13:57
 */

@ConfigurationProperties("target.string")
public class AutoConfigurationProperties {

    private String target;

    public String getTarget() {
        return target;
    }

    public void setTarget(String target) {
        this.target = target;
    }

}

4.自动配置类

package com.test;


import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * AutoConfigurationClass
 *
 * @since 2020/06/29 14:01
 */

@Configuration
@EnableConfigurationProperties(AutoConfigurationProperties.class)
@ConditionalOnClass(GetHashCodeClass.class)
public class AutoConfigurationClass {


    @Autowired
    private AutoConfigurationProperties autoConfigurationProperties;


    @ConditionalOnMissingBean
    @Bean
    public GetHashCodeClass getHashCodeClass() {
        return new GetHashCodeClass(autoConfigurationProperties.getTarget());
    }
}

5.spring.factories

在resources目录下，新建 META-INF/spring.factories

文件内容

org.springframework.boot.autoconfigure.EnableAutoConfiguration=com.test.AutoConfigurationClass

6.application.yml

target:
  string:
    target: nihao

7.完整工程目录

8.打包

工程目录下

mvn install

9.测试starter

再新建一个maven工程

完整maven依赖

<?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>org.example</groupId>
    <artifactId>testStarter</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>com.22xcode</groupId>
            <artifactId>mystarter-spring-boot-starter</artifactId>
            <version>1.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
            <version>2.2.2.RELEASE</version>
        </dependency>
    </dependencies>

</project>

10.启动类

package test;


import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
 * test.Test
 *
 * @since 2020/06/29 16:25
 */

@SpringBootApplication
public class Test {



    public static void main(String[] args) {
        SpringApplication.run(Test.class, args);

    }


}

11.BeanTest

package test;

import com.test.GetHashCodeClass;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.stereotype.Component;

/**
 * BeanTest
 *
 * @since 2020/06/29 16:30
 */
@Component
public class BeanTest implements CommandLineRunner {

    @Autowired
    private GetHashCodeClass getHashCodeClass;


    /**
     * 实际的入口函数
     *
     * @param args
     * @throws Exception
     */

    public void run(String... args) throws Exception {
        System.out.println(getHashCodeClass.getHashCode());
    }


}

12.application.yml

target:
  string:
    target: yyy

13.运行

OK

参考https://blog.csdn.net/qq_35794278/article/details/88662827