<?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>

    <!-- 用戶依賴必須指定的參數(shù) -->
    <groupId>org.example</groupId>
    <artifactId>hello-spring-boot-starter</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <!--        jdk版本-->
        <java.version>1.8</java.version>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

    <dependencies>
        <!-- 基礎(chǔ)依賴  提供了Spring Boot核心功能和默認(rèn)配置 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
            <version>2.7.18</version>
        </dependency>
        <!-- 編譯時(shí)依賴 可以幫助我們生成屬性類和配置元數(shù)據(jù)，并且設(shè)置為可選依賴，避免傳遞給其他項(xiàng)目。-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <version>2.7.18</version>
            <optional>true</optional>
        </dependency>
    </dependencies>
</project>

package com.hello.starter.properties;

/**
 *  * 描述：配置信息 實(shí)體
 * @author yss
 * @date 2024/5/1
 */
import org.springframework.boot.context.properties.ConfigurationProperties;
@ConfigurationProperties(prefix = "demo") // 指定 用戶配置文件中的前綴
public class DemoProperties {
    private String sayWhat;
    private String toWho;

    public String getSayWhat() {
        return sayWhat;
    }

    public void setSayWhat(String sayWhat) {
        this.sayWhat = sayWhat;
    }

    public String getToWho() {
        return toWho;
    }

    public void setToWho(String toWho) {
        this.toWho = toWho;
    }
}

package com.hello.starter.service;

/**
 * @author yss
 * @date 2024/5/1
 */
public class DemoService {
    public String sayWhat;
    public String toWho;
    public DemoService(String sayWhat, String toWho){
        this.sayWhat = sayWhat;
        this.toWho = toWho;
    }
    public String say(){
        return this.sayWhat + "!  " + toWho;
    }
}

package com.hello.starter.config;

import com.hello.starter.properties.DemoProperties;
import com.hello.starter.service.DemoService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * @author yss
 * @date 2024/5/1
 */
@Configuration // 標(biāo)識(shí)這是一個(gè)配置類，用來(lái)創(chuàng)建和注冊(cè)Bean對(duì)象。
//啟用屬性類，并將其注入到配置類中。
@EnableConfigurationProperties(DemoProperties.class) 
// 判斷業(yè)務(wù)功能類是否存在
@ConditionalOnClass(DemoService.class)
// 判斷用戶配置文件中是否存在指定的屬性(isopen)，
// 如果存在并且值與期望相符， 則滿足條件(開(kāi)啟相應(yīng)功能)。
@ConditionalOnProperty(
        prefix = "demo",
        name = "isopen",
        havingValue = "true"
)  
public class DemoConfig {
    @Autowired
    private DemoProperties demoProperties;
    
	// 根據(jù)屬性類和業(yè)務(wù)功能類，創(chuàng)建相應(yīng)類型的Bean對(duì)象，并注冊(cè)到應(yīng)用上下文中。
    @Bean(name = "demo")  
    public DemoService demoService(){
        return new DemoService(demoProperties.getSayWhat(), 
        demoProperties.getToWho());
    }
}

#-------starter自動(dòng)裝配---------
org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
com.hello.starter.config.DemoConfig

<!--        自定義Starter-->
<dependency>
    <groupId>org.example</groupId>
    <artifactId>hello-spring-boot-starter</artifactId>
    <version>1.0-SNAPSHOT</version>
</dependency>

demo:
  # 允許 demo作為bean注入IOC容器  一定要指明 isopen  不然項(xiàng)目無(wú)法啟動(dòng)
  isopen: true
  say-what: hello
  to-who: shf

package com.example.testStarter;

import com.hello.starter.service.DemoService;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

/**
 * @author yss
 * @date 2024/5/1
 */
@RestController
public class DemoController {

    @Resource(name = "demo")
    private DemoService demoService;

    @RequestMapping("/say")
    public String sayWhat(){
        return demoService.say();
    }
}