制作自己的SpringBootStarter

SpringBoot Starter的思想创建一个自己的SpringBoot Starter项目中引入自己的starter浏览器访问地址知其然知其所以然

SpringBoot的starter机制是如何运行的？关键流程解析 思考：为什么AutoConfigurationimportSelector要加载Spring.factories文件中的类进行配置？

一种约定大于配置的实现。引入starter相当于引入指定的功能，开箱即用依赖的管理方式，将一部分依赖已starter的方式一次性引入 创建一个自己的SpringBoot Starter

创建maven工程
引入依赖

    
        
            org.springframework.boot
            spring-boot-autoconfigure
            2.5.4
        
    

创建基础DTO

public class Piano {

    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

创建提供服务的service

@Service
public class PianoService {

    @Autowired
    private PianoProperties properties;

    public void playThePiano(String music) {
        System.out.println(properties.getPianist() + "弹了一首" + music);
    }

}

创建配置文件

@ConfigurationProperties(prefix = "zmj.piano")
public class PianoProperties {

    private boolean enable;

    private String pianist;

    public boolean isEnable() {
        return enable;
    }

    public void setEnable(boolean enable) {
        this.enable = enable;
    }

    public String getPianist() {
        return pianist;
    }

    public void setPianist(String pianist) {
        this.pianist = pianist;
    }
}

配置条件注入

@Configuration
@ConditionalOnClass(PianoService.class)
@ConditionalOnProperty(prefix = "zmj.piano", value = "enable", matchIfMissing = true)
@EnableConfigurationProperties(PianoProperties.class)
public class ZmjAutoConfiguration {

    @Bean
    @Order
    @ConditionalOnMissingBean
    public PianoService pianoService() {
        return new PianoService();
    }

}

resources/meta-INF/spring.factories 增加配置

org.springframework.boot.autoconfigure.EnableAutoConfiguration=
  org.zengmingjie.starter.ZmjAutoConfiguration

将项目install

mvn -Dmaven.test.skip=true clean install

此时在本地maven仓库就已经生成了jar包

引入starter

        
            org.zengmingjie
            starterdemo
            0.0.1-SNAPSHOT
        

新建controller，引入PianoService

@RestController
@RequestMapping("/test")
public class TestController {

    @Autowired
    private PianoService pianoService;

    @GetMapping("/piano")
    public String piano(@RequestParam String music) {
        pianoService.playThePiano(music);
        return "success";
    }

}

配置application.yaml

zmj:
  piano:
    enable: true
    pianist: '贝多芬'

ConfigurationClassPostProcessor.classAutoConfigurationimportSelector.class

https://blog.csdn.net/lemon89/article/details/79189475