第二十八章：SpringBoot使用AutoConfiguration自定义Starter

<?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.yuqiyu</groupId>
    <artifactId>chapter28</artifactId>
    <version>1.0.0</version>
    <packaging>jar</packaging>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-autoconfigure</artifactId>
            <version>1.5.4.RELEASE</version>
        </dependency>
    </dependencies>
</project>

package com.yuqiyu.chapter28;
import org.springframework.boot.context.properties.ConfigurationProperties;
/**
 * 配置文件实体映射
 * ========================
 * Created with IntelliJ IDEA.
 * User：恒宇少年
 * Date：2017/7/22
 * Time：22:51
 * 码云：http://git.oschina.net/jnyqy
 * ========================
 */
@ConfigurationProperties(prefix = "hello")
public class HelloProperties
{
    //消息内容
    private String msg = "HengYu";
    //是否显示消息内容
    private boolean show = true;

    public String getMsg() {
        return msg;
    }
    public void setMsg(String msg) {
        this.msg = msg;
    }
    public boolean isShow() {
        return show;
    }
    public void setShow(boolean show) {
        this.show = show;
    }
}

package com.yuqiyu.chapter28;

/**
 * 自定义业务实现
 * ========================
 * Created with IntelliJ IDEA.
 * User：恒宇少年
 * Date：2017/7/22
 * Time：22:54
 * 码云：http://git.oschina.net/jnyqy
 * ========================
 */
public class HelloService
{
    //消息内容
    private String msg;
    //是否显示消息内容
    private boolean show = true;

    public String sayHello()
    {
        return show ? "Hello，" + msg : "Hidden";
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

    public void setShow(boolean show) {
        this.show = show;
    }
}

package com.yuqiyu.chapter28;

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.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * 自定义starter自动化配置
 * ========================
 * Created with IntelliJ IDEA.
 * User：恒宇少年
 * Date：2017/7/22
 * Time：22:56
 * 码云：http://git.oschina.net/jnyqy
 * ========================
 */
@Configuration//开启配置
@EnableConfigurationProperties(HelloProperties.class)//开启使用映射实体对象
@ConditionalOnClass(HelloService.class)//存在HelloService时初始化该配置类
@ConditionalOnProperty//存在对应配置信息时初始化该配置类
        (
                prefix = "hello",//存在配置前缀hello
                value = "enabled",//开启
                matchIfMissing = true//缺失检查
        )
public class HelloAutoConfiguration
{

    //application.properties配置文件映射前缀实体对象
    @Autowired
    private HelloProperties helloProperties;

    /**
     * 根据条件判断不存在HelloService时初始化新bean到SpringIoc
     * @return
     */
    @Bean//创建HelloService实体bean
    @ConditionalOnMissingBean(HelloService.class)//缺失HelloService实体bean时，初始化HelloService并添加到SpringIoc
    public HelloService helloService()
    {
        System.out.println(">>>The HelloService Not Found，Execute Create New Bean.");
        HelloService helloService = new HelloService();
        helloService.setMsg(helloProperties.getMsg());//设置消息内容
        helloService.setShow(helloProperties.isShow());//设置是否显示
        return helloService;
    }
}

//
// Source code recreated from a .class file by IntelliJ IDEA
// (powered by Fernflower decompiler)
//

package org.springframework.boot.autoconfigure;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import org.springframework.context.annotation.Import;

@Target({ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@AutoConfigurationPackage
@Import({EnableAutoConfigurationImportSelector.class})
public @interface EnableAutoConfiguration {
    String ENABLED_OVERRIDE_PROPERTY = "spring.boot.enableautoconfiguration";

    Class<?>[] exclude() default {};

    String[] excludeName() default {};
}

# Initializers
org.springframework.context.ApplicationContextInitializer=\
org.springframework.boot.autoconfigure.SharedMetadataReaderFactoryContextInitializer,\
org.springframework.boot.autoconfigure.logging.AutoConfigurationReportLoggingInitializer

# Application Listeners
org.springframework.context.ApplicationListener=\
org.springframework.boot.autoconfigure.BackgroundPreinitializer

# Auto Configuration Import Listeners
org.springframework.boot.autoconfigure.AutoConfigurationImportListener=\
org.springframework.boot.autoconfigure.condition.ConditionEvaluationReportAutoConfigurationImportListener

# Auto Configuration Import Filters
org.springframework.boot.autoconfigure.AutoConfigurationImportFilter=\
org.springframework.boot.autoconfigure.condition.OnClassCondition

# Auto Configure
org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
org.springframework.boot.autoconfigure.admin.SpringApplicationAdminJmxAutoConfiguration,\
org.springframework.boot.autoconfigure.aop.AopAutoConfiguration,\
.....省略

#配置自定义Starter的自动化配置
org.springframework.boot.autoconfigure.EnableAutoConfiguration=com.yuqiyu.chapter28.HelloAutoConfiguration

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

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

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.4.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>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>                
        <!--自定义starter依赖-->
        <dependency>
            <groupId>com.yuqiyu</groupId>
            <artifactId>chapter28</artifactId>
            <version>1.0.0</version>
        </dependency>
        <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>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

#显示debug日志信息
debug=true

.....省略
>>>The HelloService Not Found，Execute Create New Bean.
.....省略
   HelloAutoConfiguration matched:
      - @ConditionalOnClass found required class 'com.yuqiyu.chapter28.HelloService'; @ConditionalOnMissingClass did not find unwanted class (OnClassCondition)
      - @ConditionalOnProperty (hello.enabled) matched (OnPropertyCondition)

   HelloAutoConfiguration#helloService matched:
      - @ConditionalOnMissingBean (types: com.yuqiyu.chapter28.HelloService; SearchStrategy: all) did not find any beans (OnBeanCondition)
.....省略

package com.yuqiyu.sample.testspringbootstarterhello;

import com.yuqiyu.chapter28.HelloService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

/**
 * 测试自定义starter自动化配置HelloService
 * ========================
 * Created with IntelliJ IDEA.
 * User：恒宇少年
 * Date：2017/7/23
 * Time：11:42
 * 码云：http://git.oschina.net/jnyqy
 * ========================
 */
@RestController
public class HelloController
{
    //注入自定义starter内逻辑
    @Autowired
    HelloService helloService;

    /**
     * 测试访问地址/hello
     * @return 格式化字符串
     */
    @RequestMapping(value = "/hello")
    public String sayHello()
    {
        return helloService.sayHello();
    }
}

Hello，HengYu

#配置自定义starter参数
hello.msg=HengYu Boy
hello.show=true

Hello，HengYu Boy