Spring Boot 入门 （一）——建一个最简单的springboot项目

创建一个最简单的springboot项目

废话不多说直接开整！！

打开eclipse新建一个maven项目，目录格式如下：

打开pom.xml文件，引入父依赖，web依赖，并设置JDK版本

<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>com.freetek</groupId>
  <artifactId>nmsc</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>war</packaging>
  
  <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.4.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.8</java.version>
    </properties>
    
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    </dependencies>
</project>

保存之后，右键项目名->maven->update project

然后编写启动类，目录结构

App.java

package com.freetek.springboot;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class App {
	public static void main(String[] args) {
		SpringApplication.run(App.class, args);
	}
}

最后，写一个Contoller类

package com.freetek.springboot.controller;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class Hello {
    @RequestMapping(value = "/hello")
    public String hello() {
        return "hello spring boot";
    }
}

@RestController ：这个注解相当于@ResponseBody 和 @Controller两个注解的组合

然后右键->run as -> java application

控制台打印如下内容表示启动成功：

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v1.4.1.RELEASE)

2017-11-29 16:57:01.315  INFO 5888 --- [           main] com.freetek.springboot.App               : Starting App on Freetek-013 with PID 5888 (E:\workspace\springboot\target\classes started by Jinqiang in E:\workspace\springboot)
2017-11-29 16:57:01.317  INFO 5888 --- [           main] com.freetek.springboot.App               : No active profile set, falling back to default profiles: default
2017-11-29 16:57:01.363  INFO 5888 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@5a63f509: startup date [Wed Nov 29 16:57:01 CST 2017]; root of context hierarchy
2017-11-29 16:57:02.732  INFO 5888 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2017-11-29 16:57:02.757  INFO 5888 --- [           main] o.apache.catalina.core.StandardService   : Starting service Tomcat
2017-11-29 16:57:02.758  INFO 5888 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.5
2017-11-29 16:57:02.877  INFO 5888 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2017-11-29 16:57:02.877  INFO 5888 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 1517 ms
2017-11-29 16:57:03.112  INFO 5888 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2017-11-29 16:57:03.116  INFO 5888 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-11-29 16:57:03.117  INFO 5888 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-11-29 16:57:03.117  INFO 5888 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-11-29 16:57:03.117  INFO 5888 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2017-11-29 16:57:03.460  INFO 5888 --- [           main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@5a63f509: startup date [Wed Nov 29 16:57:01 CST 2017]; root of context hierarchy
2017-11-29 16:57:03.548  INFO 5888 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2017-11-29 16:57:03.549  INFO 5888 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2017-11-29 16:57:03.600  INFO 5888 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-11-29 16:57:03.600  INFO 5888 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-11-29 16:57:03.649  INFO 5888 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-11-29 16:57:03.828  INFO 5888 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup
2017-11-29 16:57:04.079  INFO 5888 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
2017-11-29 16:57:04.084  INFO 5888 --- [           main] com.freetek.springboot.App               : Started App in 3.092 seconds (JVM running for 3.404)

打开浏览器，访问：http://localhost:8080/hello

返回 hello spring boot 表示成功。

over