[学习记录-Spring Boot]Spring Boot入门

Spring Boot入门

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• ​​Spring Boot入门​​
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• ​​IDEA创建SpringBoot​​
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  • ​​创建SpringBoot工程​​
  • ​​添加web功能起步依赖​​
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• ​​热部署​​
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Spring Boot入门

IDEA创建SpringBoot

创建SpringBoot工程

更新：注意这里不小心错了，要选择Maven Project

创建之后是下面的页面

添加web功能起步依赖

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

这个时候就已经创建了一个SpringBootWeb工程了，启动SpringBoot引导类，src/man/java/com.example.demo中的DemoApplication.

启动之后控制台会显示如下信息，

 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.3.3.RELEASE)

2020-08-15 11:32:49.154  INFO 15816 --- [           main] com.example.demo.DemoApplication         : Starting DemoApplication on 眸笑 with PID 15816 (D:\文件\JavaStudy\springboot\demo\target\classes started by Administrator in D:\文件\JavaStudy\springboot\demo)
2020-08-15 11:32:49.156  INFO 15816 --- [           main] com.example.demo.DemoApplication         : No active profile set, falling back to default profiles: default
2020-08-15 11:32:49.813  INFO 15816 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)
2020-08-15 11:32:49.820  INFO 15816 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2020-08-15 11:32:49.820  INFO 15816 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.37]
2020-08-15 11:32:49.893  INFO 15816 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2020-08-15 11:32:49.893  INFO 15816 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 702 ms
2020-08-15 11:32:50.032  INFO 15816 --- [           main] o.s.s.concurrent.ThreadPoolTaskExecutor  : Initializing ExecutorService 'applicationTaskExecutor'
2020-08-15 11:32:50.160  INFO 15816 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8080 (http) with context path ''
2020-08-15 11:32:50.167  INFO 15816 --- [           main] com.example.demo.DemoApplication         : Started DemoApplication in 1.314 seconds (JVM running for 2.636)

在浏览器输入localhots:8080

显示下面界面之后就代表启动成功了。

现在来做一个简单的HelloWorld!

• 创建一个SayHelloController.java

package com.example.demo;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class SayHelloController {
    @RequestMapping("/hello")
    @ResponseBody
    public String sayHello(){
        return "Hello World!";
    }
}

• 重启SpringBoot引导类，然后再浏览器输入http://localhost:8080/hello就可以访问了
  

热部署

添加依赖

        <!--热部署-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>

如果使用IDEA热部署失败可以参考这篇文章