Spring Boot入门例子

分手后的思念是犯贱 2022-08-23 05:46 197阅读 0赞

## 首先使用Maven导入必要的jar ##

<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>springboot</groupId>
      <artifactId>springboot</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <packaging>jar</packaging>
    
      <name>springboot</name>
      <url>http://maven.apache.org</url>
    
      <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
      </properties>
    
      
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>1.3.3.RELEASE</version>
        </parent>
    
    
    
      <dependencies>
    
      
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
    
        <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <scope>test</scope>
        </dependency>
      </dependencies>
    </project>

## 加入一个Controller ##

package cn.springboot.controller;
    
    import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    import cn.springboot.dto.People;
    
    @EnableAutoConfiguration
    @RestController
    public class HelloController {
    
        @RequestMapping("/")
        public String sayHello() {
            return "Hello,World!";
        }
    
        @RequestMapping("/{id}")
        public People getPeople(@PathVariable Integer id) {
            People people = new People();
            people.setId(id);
            people.setAge("13");
            people.setName("lisi");
            return people;
        }
    }

*  @RestController告诉Spring以字符串的形式渲染结果，并直接返回给调用者。
 *  @EnableAutoConfiguration 。这个注解告诉Spring Boot根据添加的jar依赖猜测你想如何配置Spring。

## 一个启动类 ##

package cn.springboot.application;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    import cn.springboot.controller.HelloController;
    
    @SpringBootApplication
    public class Application { 
    
        public static void main(String[] args) {
            SpringApplication.run(HelloController.class, args);
        }
    }

我们的main方法通过调用run，将业务委托给了Spring Boot的SpringApplication类。SpringApplication将引导我们的应用，启动Spring，相应地启动被自动配置的Tomcat web服务器。我们需要将 Example.class 作为参数传递给run方法来告诉SpringApplication谁是主要的Spring组件。为了暴露任何的命令行参数，args数组也会被传递过去。

## 启动后就可以进行访问了 ##

结果如下  
![这里写图片描述][20160610003410103]  
![这里写图片描述][20160610003428806]

### 参考 ###

官方的《Spring Boot Reference Guide》

[20160610003410103]: /images/20220721/9a0d384d25264f02831f3ec4f07bb9be.png
[20160610003428806]: /images/20220721/6259c636dd0243b985df72eba388604a.png