简单实践 java spring boot 自动配置模拟

1.概要

1.1 需求，自己写一个redis-spring-boot-starter模拟自动配置

自动配置就是在引入*-starter坐标后，可以已经spring框架的规则实现一些Bean的自动注入，并设置一些参数的默认值，且也可以在引入的工程中修改这些配置的值。这里依据这个原理模拟一下。

1.2 要点

• @Configuration
  @EnableConfigurationProperties(RedisProperties.class)
  public class RedisAutoConfigration {
      @Bean
      public Jedis jedis(RedisProperties edisProperties){
          return  new Jedis(edisProperties.getHost(),edisProperties.getPort());
• @ConfigurationProperties
  public class RedisProperties {
• <groupId>redis.clients</groupId>
  <artifactId>jedis</artifactId>
• <artifactId>redis-spring-boot-autoconfigure</artifactId>
  <version>0.0.1-SNAPSHOT</version>
• <groupId>com.xjc.springcloundtest</groupId>
  <artifactId>redis-spring-boot-starter</artifactId>
• Jedis jedis = context.getBean(Jedis.class);
  System.out.println(jedis);

1.3 关键词

• @Configuration
• @EnableConfigurationProperties(RedisProperties.class)
• @Bean
• @ConfigurationProperties
• context.getBean(Jedis.class);
• @SpringBootApplication
• ConfigurableApplicationContext context =  SpringApplication.run(Main.class); 

2.代码

2.1 父工程

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>3.2.2</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.xjc.springcloundtest</groupId><artifactId>demo23</artifactId><version>0.0.1-SNAPSHOT</version><packaging>pom</packaging><name>demo23</name><description>demo23</description><modules><module>redis-spring-boot-starter</module><module>redis-spring-boot-autoconfigure</module><module>untitled</module><module>untitled1</module></modules><properties><java.version>17</java.version></properties><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency>
<!--		&lt;!&ndash; https://mvnrepository.com/artifact/org.mybatis.spring.boot/mybatis-spring-boot-starter &ndash;&gt;<dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId><version>1.3.2</version></dependency>--></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build></project>

2.2 启动工程  redis-spring-boot-starter 

2.2.1 工程文件

<?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><parent><groupId>com.xjc.springcloundtest</groupId><artifactId>demo23</artifactId><version>0.0.1-SNAPSHOT</version></parent><artifactId>redis-spring-boot-starter</artifactId><properties><maven.compiler.source>21</maven.compiler.source><maven.compiler.target>21</maven.compiler.target><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding></properties><dependencies><dependency><groupId>com.xjc.springcloundtest</groupId><artifactId>redis-spring-boot-autoconfigure</artifactId><version>0.0.1-SNAPSHOT</version></dependency></dependencies></project>

2.3 自动配置工程 redis-spring-boot-autoconfigure

2.3.1 工程文件

<?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><parent><groupId>com.xjc.springcloundtest</groupId><artifactId>demo23</artifactId><version>0.0.1-SNAPSHOT</version></parent><artifactId>redis-spring-boot-autoconfigure</artifactId><properties><maven.compiler.source>21</maven.compiler.source><maven.compiler.target>21</maven.compiler.target><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding></properties><dependencies><dependency><groupId>redis.clients</groupId><artifactId>jedis</artifactId></dependency></dependencies></project>

2.3.2 配置类

package com.xjc.springcloundtest;import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import redis.clients.jedis.Jedis;@Configuration
@EnableConfigurationProperties(RedisProperties.class)
public class RedisAutoConfigration {@Beanpublic Jedis jedis(RedisProperties edisProperties){return  new Jedis(edisProperties.getHost(),edisProperties.getPort());}
}

2.3.3 配置数据类

package com.xjc.springcloundtest;import org.springframework.boot.context.properties.ConfigurationProperties;@ConfigurationProperties
public class RedisProperties {public int getPort() {return port;}public void setPort(int port) {this.port = port;}public String getHost() {return host;}public void setHost(String host) {this.host = host;}private String host="localhost";private int port=6379;}

2.4  使用自定义自动配置工程进行测试

2.4.1 工程文件

<?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><parent><groupId>com.xjc.springcloundtest</groupId><artifactId>demo23</artifactId><version>0.0.1-SNAPSHOT</version></parent><artifactId>untitled</artifactId><properties><maven.compiler.source>21</maven.compiler.source><maven.compiler.target>21</maven.compiler.target><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding></properties><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>com.xjc.springcloundtest</groupId><artifactId>redis-spring-boot-starter</artifactId><version>0.0.1-SNAPSHOT</version></dependency></dependencies></project>

2.4.2 主函数

package com.xjc.springcloundtest;import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
import redis.clients.jedis.Jedis;@SpringBootApplication
public class Main {public static void main(String[] args) {ConfigurableApplicationContext context =  SpringApplication.run(Main.class);System.out.println("Hello world!");Jedis jedis = context.getBean(Jedis.class);System.out.println(jedis);}
}

2.4.3 测试结果

C:\Users\ThinkPad\.jdks\openjdk-21.0.2\bin\java.exe -XX:TieredStopAtLevel=1 -Dspring.output.ansi.enabled=always -Dcom.sun.management.jmxremote -Dspring.jmx.enabled=true -Dspring.liveBeansView.mbeanDomain -Dspring.application.admin.enabled=true "-Dmanagement.endpoints.jmx.exposure.include=*" "-javaagent:D:\Program Files\JetBrains\IntelliJ IDEA 2023.3.2\lib\idea_rt.jar=61994:D:\Program Files\JetBrains\IntelliJ IDEA 2023.3.2\bin" -Dfile.encoding=UTF-8 -Dsun.stdout.encoding=UTF-8 -Dsun.stderr.encoding=UTF-8 -classpath C:\Users\ThinkPad\IdeaProjects\demo23\untitled\target\classes;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-web\3.2.2\spring-boot-starter-web-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-json\3.2.2\spring-boot-starter-json-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-databind\2.15.3\jackson-databind-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-annotations\2.15.3\jackson-annotations-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-core\2.15.3\jackson-core-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\datatype\jackson-datatype-jdk8\2.15.3\jackson-datatype-jdk8-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\datatype\jackson-datatype-jsr310\2.15.3\jackson-datatype-jsr310-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\module\jackson-module-parameter-names\2.15.3\jackson-module-parameter-names-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-tomcat\3.2.2\spring-boot-starter-tomcat-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-core\10.1.18\tomcat-embed-core-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-el\10.1.18\tomcat-embed-el-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-websocket\10.1.18\tomcat-embed-websocket-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-web\6.1.3\spring-web-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-beans\6.1.3\spring-beans-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\io\micrometer\micrometer-observation\1.12.2\micrometer-observation-1.12.2.jar;C:\Users\ThinkPad\.m2\repository\io\micrometer\micrometer-commons\1.12.2\micrometer-commons-1.12.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-webmvc\6.1.3\spring-webmvc-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-aop\6.1.3\spring-aop-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-context\6.1.3\spring-context-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-expression\6.1.3\spring-expression-6.1.3.jar;C:\Users\ThinkPad\IdeaProjects\demo23\redis-spring-boot-starter\target\classes;C:\Users\ThinkPad\IdeaProjects\demo23\redis-spring-boot-autoconfigure\target\classes;C:\Users\ThinkPad\.m2\repository\redis\clients\jedis\5.0.2\jedis-5.0.2.jar;C:\Users\ThinkPad\.m2\repository\org\apache\commons\commons-pool2\2.12.0\commons-pool2-2.12.0.jar;C:\Users\ThinkPad\.m2\repository\org\json\json\20231013\json-20231013.jar;C:\Users\ThinkPad\.m2\repository\com\google\code\gson\gson\2.10.1\gson-2.10.1.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter\3.2.2\spring-boot-starter-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot\3.2.2\spring-boot-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-autoconfigure\3.2.2\spring-boot-autoconfigure-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-logging\3.2.2\spring-boot-starter-logging-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\ch\qos\logback\logback-classic\1.4.14\logback-classic-1.4.14.jar;C:\Users\ThinkPad\.m2\repository\ch\qos\logback\logback-core\1.4.14\logback-core-1.4.14.jar;C:\Users\ThinkPad\.m2\repository\org\apache\logging\log4j\log4j-to-slf4j\2.21.1\log4j-to-slf4j-2.21.1.jar;C:\Users\ThinkPad\.m2\repository\org\apache\logging\log4j\log4j-api\2.21.1\log4j-api-2.21.1.jar;C:\Users\ThinkPad\.m2\repository\org\slf4j\jul-to-slf4j\2.0.11\jul-to-slf4j-2.0.11.jar;C:\Users\ThinkPad\.m2\repository\jakarta\annotation\jakarta.annotation-api\2.1.1\jakarta.annotation-api-2.1.1.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-core\6.1.3\spring-core-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-jcl\6.1.3\spring-jcl-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\yaml\snakeyaml\2.2\snakeyaml-2.2.jar;C:\Users\ThinkPad\.m2\repository\org\slf4j\slf4j-api\2.0.11\slf4j-api-2.0.11.jar com.xjc.springcloundtest.Main.   ____          _            __ _ _/\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \\\/  ___)| |_)| | | | | || (_| |  ) ) ) )'  |____| .__|_| |_|_| |_\__, | / / / /=========|_|==============|___/=/_/_/_/:: Spring Boot ::                (v3.2.2)2024-02-02T16:04:44.406+08:00  INFO 22288 --- [           main] com.xjc.springcloundtest.Main            : Starting Main using Java 21.0.2 with PID 22288 (C:\Users\ThinkPad\IdeaProjects\demo23\untitled\target\classes started by ThinkPad in C:\Users\ThinkPad\IdeaProjects\demo23)
2024-02-02T16:04:44.410+08:00  INFO 22288 --- [           main] com.xjc.springcloundtest.Main            : No active profile set, falling back to 1 default profile: "default"
2024-02-02T16:04:45.388+08:00  INFO 22288 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port 8080 (http)
2024-02-02T16:04:45.400+08:00  INFO 22288 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2024-02-02T16:04:45.400+08:00  INFO 22288 --- [           main] o.apache.catalina.core.StandardEngine    : Starting Servlet engine: [Apache Tomcat/10.1.18]
2024-02-02T16:04:45.452+08:00  INFO 22288 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2024-02-02T16:04:45.453+08:00  INFO 22288 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 978 ms
2024-02-02T16:04:45.963+08:00  INFO 22288 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port 8080 (http) with context path ''
2024-02-02T16:04:45.970+08:00  INFO 22288 --- [           main] com.xjc.springcloundtest.Main            : Started Main in 2.054 seconds (process running for 2.705)
Hello world!
Jedis{Connection{DefaultJedisSocketFactory{localhost:6379}}}

3 补充实验

3.1 概要

实验条件加载的效果，给对象加一个软件，如果用户已经创建了这个对象，就不再创建了。

3.2 代码 

3.2 添加条件 

3.2.1 配置文件变更 @ConditionalOnMissingBean(name = "jedis")

@Configuration
@EnableConfigurationProperties(RedisProperties.class)
public class RedisAutoConfigration {@Bean@ConditionalOnMissingBean(name = "jedis")public Jedis jedis(RedisProperties edisProperties){System.out.println("自动配置Jedis");return  new Jedis(edisProperties.getHost(),edisProperties.getPort());}
}

3.2.1 测试函数变更 添加Jedis 对象的Bean

@SpringBootApplication
public class Main {public static void main(String[] args) {ConfigurableApplicationContext context =  SpringApplication.run(Main.class);System.out.println("Hello world!");//Jedis jedis = context.getBean(Jedis.class);Object o = context.getBean("jedis");System.out.println(o);}@Beanpublic Jedis jedis2(){return  new Jedis("localhost",6379);}
}

3.3 测试结果

C:\Users\ThinkPad\.jdks\openjdk-21.0.2\bin\java.exe -XX:TieredStopAtLevel=1 -Dspring.output.ansi.enabled=always -Dcom.sun.management.jmxremote -Dspring.jmx.enabled=true -Dspring.liveBeansView.mbeanDomain -Dspring.application.admin.enabled=true "-Dmanagement.endpoints.jmx.exposure.include=*" "-javaagent:D:\Program Files\JetBrains\IntelliJ IDEA 2023.3.2\lib\idea_rt.jar=63505:D:\Program Files\JetBrains\IntelliJ IDEA 2023.3.2\bin" -Dfile.encoding=UTF-8 -Dsun.stdout.encoding=UTF-8 -Dsun.stderr.encoding=UTF-8 -classpath C:\Users\ThinkPad\IdeaProjects\demo23\untitled\target\classes;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-web\3.2.2\spring-boot-starter-web-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-json\3.2.2\spring-boot-starter-json-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-databind\2.15.3\jackson-databind-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-annotations\2.15.3\jackson-annotations-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-core\2.15.3\jackson-core-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\datatype\jackson-datatype-jdk8\2.15.3\jackson-datatype-jdk8-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\datatype\jackson-datatype-jsr310\2.15.3\jackson-datatype-jsr310-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\module\jackson-module-parameter-names\2.15.3\jackson-module-parameter-names-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-tomcat\3.2.2\spring-boot-starter-tomcat-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-core\10.1.18\tomcat-embed-core-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-el\10.1.18\tomcat-embed-el-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-websocket\10.1.18\tomcat-embed-websocket-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-web\6.1.3\spring-web-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-beans\6.1.3\spring-beans-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\io\micrometer\micrometer-observation\1.12.2\micrometer-observation-1.12.2.jar;C:\Users\ThinkPad\.m2\repository\io\micrometer\micrometer-commons\1.12.2\micrometer-commons-1.12.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-webmvc\6.1.3\spring-webmvc-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-aop\6.1.3\spring-aop-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-context\6.1.3\spring-context-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-expression\6.1.3\spring-expression-6.1.3.jar;C:\Users\ThinkPad\IdeaProjects\demo23\redis-spring-boot-starter\target\classes;C:\Users\ThinkPad\IdeaProjects\demo23\redis-spring-boot-autoconfigure\target\classes;C:\Users\ThinkPad\.m2\repository\redis\clients\jedis\5.0.2\jedis-5.0.2.jar;C:\Users\ThinkPad\.m2\repository\org\apache\commons\commons-pool2\2.12.0\commons-pool2-2.12.0.jar;C:\Users\ThinkPad\.m2\repository\org\json\json\20231013\json-20231013.jar;C:\Users\ThinkPad\.m2\repository\com\google\code\gson\gson\2.10.1\gson-2.10.1.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter\3.2.2\spring-boot-starter-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot\3.2.2\spring-boot-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-autoconfigure\3.2.2\spring-boot-autoconfigure-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-logging\3.2.2\spring-boot-starter-logging-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\ch\qos\logback\logback-classic\1.4.14\logback-classic-1.4.14.jar;C:\Users\ThinkPad\.m2\repository\ch\qos\logback\logback-core\1.4.14\logback-core-1.4.14.jar;C:\Users\ThinkPad\.m2\repository\org\apache\logging\log4j\log4j-to-slf4j\2.21.1\log4j-to-slf4j-2.21.1.jar;C:\Users\ThinkPad\.m2\repository\org\apache\logging\log4j\log4j-api\2.21.1\log4j-api-2.21.1.jar;C:\Users\ThinkPad\.m2\repository\org\slf4j\jul-to-slf4j\2.0.11\jul-to-slf4j-2.0.11.jar;C:\Users\ThinkPad\.m2\repository\jakarta\annotation\jakarta.annotation-api\2.1.1\jakarta.annotation-api-2.1.1.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-core\6.1.3\spring-core-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-jcl\6.1.3\spring-jcl-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\yaml\snakeyaml\2.2\snakeyaml-2.2.jar;C:\Users\ThinkPad\.m2\repository\org\slf4j\slf4j-api\2.0.11\slf4j-api-2.0.11.jar com.xjc.springcloundtest.Main.   ____          _            __ _ _/\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \\\/  ___)| |_)| | | | | || (_| |  ) ) ) )'  |____| .__|_| |_|_| |_\__, | / / / /=========|_|==============|___/=/_/_/_/:: Spring Boot ::                (v3.2.2)2024-02-02T16:59:08.925+08:00  INFO 42840 --- [           main] com.xjc.springcloundtest.Main            : Starting Main using Java 21.0.2 with PID 42840 (C:\Users\ThinkPad\IdeaProjects\demo23\untitled\target\classes started by ThinkPad in C:\Users\ThinkPad\IdeaProjects\demo23)
2024-02-02T16:59:08.929+08:00  INFO 42840 --- [           main] com.xjc.springcloundtest.Main            : No active profile set, falling back to 1 default profile: "default"
2024-02-02T16:59:09.780+08:00  INFO 42840 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port 8080 (http)
2024-02-02T16:59:09.790+08:00  INFO 42840 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2024-02-02T16:59:09.790+08:00  INFO 42840 --- [           main] o.apache.catalina.core.StandardEngine    : Starting Servlet engine: [Apache Tomcat/10.1.18]
2024-02-02T16:59:09.833+08:00  INFO 42840 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2024-02-02T16:59:09.834+08:00  INFO 42840 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 843 ms
自动配置Jedis
2024-02-02T16:59:10.281+08:00  INFO 42840 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port 8080 (http) with context path ''
2024-02-02T16:59:10.287+08:00  INFO 42840 --- [           main] com.xjc.springcloundtest.Main            : Started Main in 1.831 seconds (process running for 2.547)
Hello world!
Jedis{Connection{DefaultJedisSocketFactory{localhost:6379}}}Process finished with exit code 130

3.4 让两处的名称相同

3.4.1 代码

//自动配置处 
@Bean@ConditionalOnMissingBean(name = "jedis")public Jedis jedis(RedisProperties edisProperties){System.out.println("自动配置Jedis");return  new Jedis(edisProperties.getHost(),edisProperties.getPort());}
//主动配置出
@Beanpublic Jedis jedis(){return  new Jedis("localhost",6379);}

3.4.2 测结果 还没有到加载bena的时候就报错了

C:\Users\ThinkPad\.jdks\openjdk-21.0.2\bin\java.exe -XX:TieredStopAtLevel=1 -Dspring.output.ansi.enabled=always -Dcom.sun.management.jmxremote -Dspring.jmx.enabled=true -Dspring.liveBeansView.mbeanDomain -Dspring.application.admin.enabled=true "-Dmanagement.endpoints.jmx.exposure.include=*" "-javaagent:D:\Program Files\JetBrains\IntelliJ IDEA 2023.3.2\lib\idea_rt.jar=65274:D:\Program Files\JetBrains\IntelliJ IDEA 2023.3.2\bin" -Dfile.encoding=UTF-8 -Dsun.stdout.encoding=UTF-8 -Dsun.stderr.encoding=UTF-8 -classpath C:\Users\ThinkPad\IdeaProjects\demo23\untitled\target\classes;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-web\3.2.2\spring-boot-starter-web-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-json\3.2.2\spring-boot-starter-json-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-databind\2.15.3\jackson-databind-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-annotations\2.15.3\jackson-annotations-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-core\2.15.3\jackson-core-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\datatype\jackson-datatype-jdk8\2.15.3\jackson-datatype-jdk8-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\datatype\jackson-datatype-jsr310\2.15.3\jackson-datatype-jsr310-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\module\jackson-module-parameter-names\2.15.3\jackson-module-parameter-names-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-tomcat\3.2.2\spring-boot-starter-tomcat-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-core\10.1.18\tomcat-embed-core-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-el\10.1.18\tomcat-embed-el-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-websocket\10.1.18\tomcat-embed-websocket-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-web\6.1.3\spring-web-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-beans\6.1.3\spring-beans-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\io\micrometer\micrometer-observation\1.12.2\micrometer-observation-1.12.2.jar;C:\Users\ThinkPad\.m2\repository\io\micrometer\micrometer-commons\1.12.2\micrometer-commons-1.12.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-webmvc\6.1.3\spring-webmvc-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-aop\6.1.3\spring-aop-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-context\6.1.3\spring-context-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-expression\6.1.3\spring-expression-6.1.3.jar;C:\Users\ThinkPad\IdeaProjects\demo23\redis-spring-boot-starter\target\classes;C:\Users\ThinkPad\IdeaProjects\demo23\redis-spring-boot-autoconfigure\target\classes;C:\Users\ThinkPad\.m2\repository\redis\clients\jedis\5.0.2\jedis-5.0.2.jar;C:\Users\ThinkPad\.m2\repository\org\apache\commons\commons-pool2\2.12.0\commons-pool2-2.12.0.jar;C:\Users\ThinkPad\.m2\repository\org\json\json\20231013\json-20231013.jar;C:\Users\ThinkPad\.m2\repository\com\google\code\gson\gson\2.10.1\gson-2.10.1.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter\3.2.2\spring-boot-starter-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot\3.2.2\spring-boot-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-autoconfigure\3.2.2\spring-boot-autoconfigure-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-logging\3.2.2\spring-boot-starter-logging-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\ch\qos\logback\logback-classic\1.4.14\logback-classic-1.4.14.jar;C:\Users\ThinkPad\.m2\repository\ch\qos\logback\logback-core\1.4.14\logback-core-1.4.14.jar;C:\Users\ThinkPad\.m2\repository\org\apache\logging\log4j\log4j-to-slf4j\2.21.1\log4j-to-slf4j-2.21.1.jar;C:\Users\ThinkPad\.m2\repository\org\apache\logging\log4j\log4j-api\2.21.1\log4j-api-2.21.1.jar;C:\Users\ThinkPad\.m2\repository\org\slf4j\jul-to-slf4j\2.0.11\jul-to-slf4j-2.0.11.jar;C:\Users\ThinkPad\.m2\repository\jakarta\annotation\jakarta.annotation-api\2.1.1\jakarta.annotation-api-2.1.1.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-core\6.1.3\spring-core-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-jcl\6.1.3\spring-jcl-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\yaml\snakeyaml\2.2\snakeyaml-2.2.jar;C:\Users\ThinkPad\.m2\repository\org\slf4j\slf4j-api\2.0.11\slf4j-api-2.0.11.jar com.xjc.springcloundtest.Main.   ____          _            __ _ _/\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \\\/  ___)| |_)| | | | | || (_| |  ) ) ) )'  |____| .__|_| |_|_| |_\__, | / / / /=========|_|==============|___/=/_/_/_/:: Spring Boot ::                (v3.2.2)2024-02-02T18:39:34.394+08:00  INFO 42764 --- [           main] com.xjc.springcloundtest.Main            : Starting Main using Java 21.0.2 with PID 42764 (C:\Users\ThinkPad\IdeaProjects\demo23\untitled\target\classes started by ThinkPad in C:\Users\ThinkPad\IdeaProjects\demo23)
2024-02-02T18:39:34.396+08:00  INFO 42764 --- [           main] com.xjc.springcloundtest.Main            : No active profile set, falling back to 1 default profile: "default"
2024-02-02T18:39:34.729+08:00  WARN 42764 --- [           main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.support.BeanDefinitionOverrideException: Invalid bean definition with name 'jedis' defined in com.xjc.springcloundtest.Main: Cannot register bean definition [Root bean: class [null]; scope=; abstract=false; lazyInit=null; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=main; factoryMethodName=jedis; initMethodNames=null; destroyMethodNames=[(inferred)]; defined in com.xjc.springcloundtest.Main] for bean 'jedis' since there is already [Root bean: class [null]; scope=; abstract=false; lazyInit=null; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=redisAutoConfigration; factoryMethodName=jedis; initMethodNames=null; destroyMethodNames=[(inferred)]; defined in class path resource [com/xjc/springcloundtest/RedisAutoConfigration.class]] bound.
2024-02-02T18:39:34.735+08:00  INFO 42764 --- [           main] .s.b.a.l.ConditionEvaluationReportLogger : Error starting ApplicationContext. To display the condition evaluation report re-run your application with 'debug' enabled.
2024-02-02T18:39:34.754+08:00 ERROR 42764 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : ***************************
APPLICATION FAILED TO START
***************************Description:The bean 'jedis', defined in com.xjc.springcloundtest.Main, could not be registered. A bean with that name has already been defined in class path resource [com/xjc/springcloundtest/RedisAutoConfigration.class] and overriding is disabled.Action:Consider renaming one of the beans or enabling overriding by setting spring.main.allow-bean-definition-overriding=trueProcess finished with exit code 1

3.4.3 添加配置

spring:main:allow-bean-definition-overriding: true

C:\Users\ThinkPad\.jdks\openjdk-21.0.2\bin\java.exe -XX:TieredStopAtLevel=1 -Dspring.output.ansi.enabled=always -Dcom.sun.management.jmxremote -Dspring.jmx.enabled=true -Dspring.liveBeansView.mbeanDomain -Dspring.application.admin.enabled=true "-Dmanagement.endpoints.jmx.exposure.include=*" "-javaagent:D:\Program Files\JetBrains\IntelliJ IDEA 2023.3.2\lib\idea_rt.jar=65297:D:\Program Files\JetBrains\IntelliJ IDEA 2023.3.2\bin" -Dfile.encoding=UTF-8 -Dsun.stdout.encoding=UTF-8 -Dsun.stderr.encoding=UTF-8 -classpath C:\Users\ThinkPad\IdeaProjects\demo23\untitled\target\classes;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-web\3.2.2\spring-boot-starter-web-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-json\3.2.2\spring-boot-starter-json-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-databind\2.15.3\jackson-databind-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-annotations\2.15.3\jackson-annotations-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\core\jackson-core\2.15.3\jackson-core-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\datatype\jackson-datatype-jdk8\2.15.3\jackson-datatype-jdk8-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\datatype\jackson-datatype-jsr310\2.15.3\jackson-datatype-jsr310-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\com\fasterxml\jackson\module\jackson-module-parameter-names\2.15.3\jackson-module-parameter-names-2.15.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-tomcat\3.2.2\spring-boot-starter-tomcat-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-core\10.1.18\tomcat-embed-core-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-el\10.1.18\tomcat-embed-el-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\apache\tomcat\embed\tomcat-embed-websocket\10.1.18\tomcat-embed-websocket-10.1.18.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-web\6.1.3\spring-web-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-beans\6.1.3\spring-beans-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\io\micrometer\micrometer-observation\1.12.2\micrometer-observation-1.12.2.jar;C:\Users\ThinkPad\.m2\repository\io\micrometer\micrometer-commons\1.12.2\micrometer-commons-1.12.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-webmvc\6.1.3\spring-webmvc-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-aop\6.1.3\spring-aop-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-context\6.1.3\spring-context-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-expression\6.1.3\spring-expression-6.1.3.jar;C:\Users\ThinkPad\IdeaProjects\demo23\redis-spring-boot-starter\target\classes;C:\Users\ThinkPad\IdeaProjects\demo23\redis-spring-boot-autoconfigure\target\classes;C:\Users\ThinkPad\.m2\repository\redis\clients\jedis\5.0.2\jedis-5.0.2.jar;C:\Users\ThinkPad\.m2\repository\org\apache\commons\commons-pool2\2.12.0\commons-pool2-2.12.0.jar;C:\Users\ThinkPad\.m2\repository\org\json\json\20231013\json-20231013.jar;C:\Users\ThinkPad\.m2\repository\com\google\code\gson\gson\2.10.1\gson-2.10.1.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter\3.2.2\spring-boot-starter-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot\3.2.2\spring-boot-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-autoconfigure\3.2.2\spring-boot-autoconfigure-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\boot\spring-boot-starter-logging\3.2.2\spring-boot-starter-logging-3.2.2.jar;C:\Users\ThinkPad\.m2\repository\ch\qos\logback\logback-classic\1.4.14\logback-classic-1.4.14.jar;C:\Users\ThinkPad\.m2\repository\ch\qos\logback\logback-core\1.4.14\logback-core-1.4.14.jar;C:\Users\ThinkPad\.m2\repository\org\apache\logging\log4j\log4j-to-slf4j\2.21.1\log4j-to-slf4j-2.21.1.jar;C:\Users\ThinkPad\.m2\repository\org\apache\logging\log4j\log4j-api\2.21.1\log4j-api-2.21.1.jar;C:\Users\ThinkPad\.m2\repository\org\slf4j\jul-to-slf4j\2.0.11\jul-to-slf4j-2.0.11.jar;C:\Users\ThinkPad\.m2\repository\jakarta\annotation\jakarta.annotation-api\2.1.1\jakarta.annotation-api-2.1.1.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-core\6.1.3\spring-core-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\springframework\spring-jcl\6.1.3\spring-jcl-6.1.3.jar;C:\Users\ThinkPad\.m2\repository\org\yaml\snakeyaml\2.2\snakeyaml-2.2.jar;C:\Users\ThinkPad\.m2\repository\org\slf4j\slf4j-api\2.0.11\slf4j-api-2.0.11.jar com.xjc.springcloundtest.Main.   ____          _            __ _ _/\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \\\/  ___)| |_)| | | | | || (_| |  ) ) ) )'  |____| .__|_| |_|_| |_\__, | / / / /=========|_|==============|___/=/_/_/_/:: Spring Boot ::                (v3.2.2)2024-02-02T18:41:04.833+08:00  INFO 40908 --- [           main] com.xjc.springcloundtest.Main            : Starting Main using Java 21.0.2 with PID 40908 (C:\Users\ThinkPad\IdeaProjects\demo23\untitled\target\classes started by ThinkPad in C:\Users\ThinkPad\IdeaProjects\demo23)
2024-02-02T18:41:04.835+08:00  INFO 40908 --- [           main] com.xjc.springcloundtest.Main            : No active profile set, falling back to 1 default profile: "default"
2024-02-02T18:41:05.636+08:00  INFO 40908 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port 8080 (http)
2024-02-02T18:41:05.648+08:00  INFO 40908 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2024-02-02T18:41:05.648+08:00  INFO 40908 --- [           main] o.apache.catalina.core.StandardEngine    : Starting Servlet engine: [Apache Tomcat/10.1.18]
2024-02-02T18:41:05.696+08:00  INFO 40908 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2024-02-02T18:41:05.696+08:00  INFO 40908 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 805 ms
2024-02-02T18:41:06.119+08:00  INFO 40908 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port 8080 (http) with context path ''
2024-02-02T18:41:06.124+08:00  INFO 40908 --- [           main] com.xjc.springcloundtest.Main            : Started Main in 1.856 seconds (process running for 2.624)
Hello world!
Jedis{Connection{DefaultJedisSocketFactory{localhost:6379}}}

这时候才达到对比的效果

@Bean@ConditionalOnMissingBean(name = "jedis")public Jedis jedis(RedisProperties edisProperties){System.out.println("自动配置Jedis");return  new Jedis(edisProperties.getHost(),edisProperties.getPort());}