springboot入门之程序的编写

青旅半醒 2021-11-02 05:01 251阅读 0赞

如果想进行springboot的开发，需要使用Maven或其他管理工具来完成这一过程。

springboot运行以web项目为主

开发项目只需按照官方文档来  ↵

↵

如果想进行springboot的开发，需要使用Maven或其他想募管理工具来完成这一过程

springboot运行以web项目

开发项目的具体模板依赖可以参考官方文档 [https://start.spring.io/][https_start.spring.io]

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explore the project后选择本地路径，解压该文件到eclipse工作路径，在eclipse中导入该项目即可创建初步的maven工程。

本文参考此视频编写 ： [https://www.bilibili.com/video/av61303794][https_www.bilibili.com_video_av61303794]

步骤：

**1.创建一个maven工程**

**2.导入依赖springboot相关的依赖**

<table style="width:500px;"> 
 <tbody> 
 <tr> 
 <td> &nbsp;&nbsp; &nbsp;&lt;parent&gt; &nbsp; &nbsp; &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; &nbsp; &nbsp; &lt;artifactId&gt;spring-boot-starter-parent&lt;/artifactId&gt; &nbsp; &nbsp; &lt;version&gt;2.1.7.RELEASE&lt;/version&gt; &nbsp; &nbsp; &lt;relativePath/&gt; &lt;!-- lookup parent from repository --&gt; &nbsp; &lt;/parent&gt; &nbsp;&lt;dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;artifactId&gt;spring-boot-starter-web&lt;/artifactId&gt; &nbsp;&lt;/dependency&gt; </td> 
 </tr> 
 </tbody> 
</table>

**3.编写一个主程序，启动springboot应用**

<table style="width:500px;"> 
 <tbody> 
 <tr> 
 <td>import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; /** &nbsp;*&nbsp; &nbsp;* @author taqsbj &nbsp;* @SpringBootApplication标注一个主程序，说明这是一个springboot应用 &nbsp;* &nbsp;*/ @SpringBootApplication public class App&nbsp; { &nbsp; &nbsp; public static void main( String[] args ) &nbsp; &nbsp; { &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;//将spring应用启动 &nbsp; &nbsp; &nbsp; &nbsp; SpringApplication.run(App.class, args); &nbsp; &nbsp; } }</td> 
 </tr> 
 </tbody> 
</table>

**4.编写所需的相关的Controller等**

**，如：**

<table style="width:500px;"> 
 <tbody> 
 <tr> 
 <td>&nbsp; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.ResponseBody; &nbsp; @Controller public class UserController { &nbsp;&nbsp; &nbsp;@RequestMapping("/hello") &nbsp;&nbsp; &nbsp;@ResponseBody &nbsp;&nbsp; &nbsp;public String hello() { &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;return "hello,world"; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp;&nbsp; &nbsp;} &nbsp; &nbsp;&nbsp; &nbsp;@RequestMapping("/index") &nbsp;&nbsp; &nbsp; &nbsp;&nbsp; &nbsp;public String index(Model model) { &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;model.addAttribute("name", "sheryll"); &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;model.addAttribute("age", 20); &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;model.addAttribute("info", "我是一个爱学习小淘气"); &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;return "index"; &nbsp;&nbsp; &nbsp;} &nbsp;&nbsp; &nbsp; }</td> 
 </tr> 
 </tbody> 
</table>

**5.测试程序**

**     **直接运行main方法（启动）

localhost://8080/hello（访问hello）

locallhost://8080/index(访问index)

6.运行主程序测试

导入<build>插件

<table style="width:500px;"> 
 <tbody> 
 <tr> 
 <td>&lt;!-- 插件，此插件可以将应用打包成一个可执行的jar包 --&gt; &nbsp; &nbsp; &lt;build&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;plugins&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;plugin&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;artifactId&gt;spring-boot-maven-plugin&lt;/artifactId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/plugin&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/plugins&gt; &nbsp; &nbsp; &nbsp; &lt;/build&gt;</td> 
 </tr> 
 </tbody> 
</table>

将这个应用导成jar包后，可在命令窗口使用 java -jar 命令运行。

完整的pom.xml配置文件如下：

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 <tbody> 
 <tr> 
 <td> &lt;project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" &nbsp; xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"&gt; &nbsp; &lt;modelVersion&gt;4.0.0&lt;/modelVersion&gt; &nbsp; &lt;groupId&gt;com&lt;/groupId&gt; &nbsp; &lt;artifactId&gt;SpringBoot-1&lt;/artifactId&gt; &nbsp; &lt;version&gt;0.0.1-SNAPSHOT&lt;/version&gt; &nbsp; &nbsp; &lt;name&gt;SpringBoot-1&lt;/name&gt; &nbsp; &lt;url&gt;http://maven.apache.org&lt;/url&gt; &nbsp; &lt;properties&gt; &nbsp; &nbsp; &lt;jdk.version&gt;1.8&lt;/jdk.version&gt; &nbsp; &nbsp; &lt;project.build.sourceEncoding&gt;UTF-8&lt;/project.build.sourceEncoding&gt; &nbsp; &lt;/properties&gt; &nbsp; &nbsp; &lt;!--Springboot相关jar包版本--&gt; &nbsp; &lt;packaging&gt;jar&lt;/packaging&gt; &nbsp; &nbsp;&lt;parent&gt; &nbsp; &nbsp; &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; &nbsp; &nbsp; &lt;artifactId&gt;spring-boot-starter-parent&lt;/artifactId&gt; &nbsp; &nbsp; &lt;version&gt;2.1.7.RELEASE&lt;/version&gt; &nbsp; &lt;/parent&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;!-- 相关jar包 --&gt; &nbsp; &nbsp; &lt;dependencies&gt; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&lt;!-- Springboot核心jar包 --&gt; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&lt;dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;artifactId&gt;spring-boot-starter&lt;/artifactId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;!-- web开发包：包含Tomcat和Springmvc --&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;artifactId&gt;spring-boot-starter-web&lt;/artifactId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;!-- thymeleaf --&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;artifactId&gt;spring-boot-starter-thymeleaf&lt;/artifactId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;!-- jdbc链接容器 --&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;groupId&gt;mysql&lt;/groupId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;artifactId&gt;mysql-connector-java&lt;/artifactId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;!-- Junit测试jar包 --&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;groupId&gt;junit&lt;/groupId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;artifactId&gt;junit&lt;/artifactId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;scope&gt;test&lt;/scope&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;!-- springboot热部署（凡是文件修改保存后，自动重启） --&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;artifactId&gt;spring-boot-devtools&lt;/artifactId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;optional&gt;true&lt;/optional&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;scope&gt;runtime&lt;/scope&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;!-- jpa（已包含hibernate） --&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;dependency&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&lt;artifactId&gt;spring-boot-starter-data-jpa&lt;/artifactId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/dependency&gt; &nbsp; &nbsp; &lt;/dependencies&gt; &nbsp; &nbsp; &lt;!-- 插件，此插件可以将应用打包成一个可执行的jar包 --&gt; &nbsp; &nbsp; &lt;build&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;plugins&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;plugin&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;groupId&gt;org.springframework.boot&lt;/groupId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;artifactId&gt;spring-boot-maven-plugin&lt;/artifactId&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;configuration&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;fork&gt;true&lt;/fork&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;addResources&gt;true&lt;/addResources&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/configuration&gt; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/plugin&gt; &nbsp; &nbsp; &nbsp; &nbsp; &lt;/plugins&gt; &nbsp; &nbsp; &nbsp; &lt;/build&gt; &lt;/project&gt; &nbsp; </td> 
 </tr> 
 </tbody> 
</table>

注意：版本号要与eclipse的设置一致

更复杂的工程：

创建resources文件夹（src/main/java/resources）在该路径下创建新的文件命名为application.yml进行服务配置

如下：

<table style="width:500px;"> 
 <tbody> 
 <tr> 
 <td> server: &nbsp; port: 80 &nbsp; session-timeout: 30 &nbsp; tomcat.max-threads: 0 &nbsp; tomcat.uri-encoding: UTF-8 &nbsp;&nbsp; &nbsp; #spring相关配置 &nbsp; spring: &nbsp; thymeleaf: &nbsp; &nbsp; prefix: classpath:/templates/ &nbsp; &nbsp; suffix: .html &nbsp; &nbsp; mode: HTML5 &nbsp; &nbsp; encoding: UTF-8 &nbsp; &nbsp; content-type: text/html &nbsp; &nbsp; cache: false &nbsp;#配置数据库相关信息 &nbsp; datasource: &nbsp; &nbsp; url: jdbc:mysql://localhost:端口号/数据库名 &nbsp; &nbsp; driver-class-name: com.mysql.jdbc.Driver &nbsp; &nbsp; username: root &nbsp; &nbsp; password: 数据库密码 &nbsp; &nbsp; initial-size: 10 &nbsp; &nbsp; max-active: 20 &nbsp; &nbsp; max-idle: 8 &nbsp; &nbsp; min-idle: 8 &nbsp;#配置jpa（hibernate） &nbsp; jpa: &nbsp; &nbsp;database: mysql &nbsp; &nbsp;show-sql: true &nbsp; &nbsp;hibernate: &nbsp; &nbsp;ddl-auto: update &nbsp; &nbsp;naming: &nbsp; &nbsp;physical-strategy: org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy &nbsp; &nbsp; database-platform: org.hibernate.dialect.MySQL5InnoDBDialect&nbsp; </td> 
 </tr> 
 </tbody> 
</table>

在mysql中创建的数据库要与之对应 保持一致

利用bean实现与前台页面的交互

利用servlet获取数据（包括接口和实现（接口的）类）

新建controller类

新建index.html前台页面展示获取到的后台数据

注意：在前端显示时通常需要用到thymeleaf(相当于c标签)

需要：

在pom.xml中添加thymeleaf配置

在resources文件夹下分别创建templates和static文件夹，分别存放html文件和css、js文件

[https_start.spring.io]: https://start.spring.io/
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[https_www.bilibili.com_video_av61303794]: https://www.bilibili.com/video/av61303794