spring boot 自定义starter的实现教程
spring boot 使用 starter 解决了很多配置问题,但是,他是怎么来解决这些问题的呢? 这里通过一个简单的例子,来看一下,starter是怎么来设置默认配置的. 一. 建 starter 项目 自定义的starter,项目命名规范是: 自定义名-spring-boot-starter 先来看一下,我最后的目录结构 1. 修改pom.xml文件 <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.elvin</groupId> <artifactId>my-spring-boot-starter</artifactId> <version>1.0-SNAPSHOT</version> <packaging>jar</packaging> <name>my-spring-boot-starter</name> <url>http://maven.apache.org</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-autoconfigure</artifactId> <version>1.5.9.RELEASE</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>3.8.1</version> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>2.3.2</version> <configuration> <source>1.8</source> <target>1.8</target> </configuration> </plugin> </plugins> </build> </project> 其实只是加入了 spring-boot-autoconfigure App文件中的main方法,我注释掉了,这个在这里没有用到 2. 配置属性对应的接收文件 package org.elvin; import org.springframework.boot.context.properties.ConfigurationProperties;/** * author: Elvin * Date: 2017/12/12 14:51 * Description: */ @ConfigurationProperties(prefix = "hello") public class HelloServiceProperties { //默认配置内容 private static final String MSG = "world"; private String msg = MSG; public String getMsg() { return msg; } public void setMsg(String msg) { this.msg = msg; } } 3. 对外Service package org.elvin; /** * author: Elvin * Date: 2017/12/12 14:55 * Description: */ public class HelloService { private String msg; public String sayHello(){ return "Hello " + msg; } public String getMsg() { return msg; } public void setMsg(String msg) { this.msg = msg; } } 4. 对外service与配置对应文件关联 package org.elvin; 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; /** * author: Elvin * Date: 2017/12/12 14:59 * Description: */ @Configuration @EnableConfigurationProperties(HelloServiceProperties.class) @ConditionalOnClass(HelloService.class) @ConditionalOnProperty(prefix = "hello",value="enabled",matchIfMissing =true ) public class HelloServiceAutoConfiguration { @Autowired private HelloServiceProperties helloServiceProperties; @Bean @ConditionalOnMissingBean(HelloService.class) public HelloService helloService(){ HelloService helloService = new HelloService(); helloService.setMsg(helloServiceProperties.getMsg()); return helloService; } } 5. starter配置 : spring.factories org.springframework.boot.autoconfigure.EnableAutoConfiguration=org.elvin.HelloServiceAutoConfiguration 做完这些之后,通过 mvn clean install,打包到maven库里面 二. spring boot 项目使用 新建一个spring boot 项目,选择web即可. 目录结构: 先看一下引用pom.xml <dependency> <groupId>org.elvin</groupId> <artifactId>my-spring-boot-starter</artifactId> <version>1.0-SNAPSHOT</version> </dependency> 再看一下HelloController package org.elvin.learn.springboot.controller; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import org.elvin.*; /** * author: Elvin * Date: 2017/12/12 15:34 * Description: */ @RestController @RequestMapping("hello") public class HelloController { @Autowired private HelloService helloService; @RequestMapping("index") public String index(){ return helloService.sayHello(); } } 这里的 HelloService 就是 前面自定义 starter 里面的. 1. 结果: 未配置情况下,应该是输出 hello world 2. 在配置文件中,加入 hello.msg=hahahahahah 这个例子很简单,只是显示一下主要的过程,别的都是各插件自己的逻辑判断了. 参考资料: JavaEE开发的颠覆者 Spring Boot实战 以上这篇spring boot 自定义starter的实现教程就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持编程小技巧。 (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |