1.   设置spring boot的parent

             
      
       org.springframework.boot
              
      
       spring-boot-starter-parent
              
      
       1.5.2.RELEASE
          
     

 

说明：Spring boot的项目必须要将parent设置为spring boot的parent，该parent包含了大量默认的配置，大大简化了我们的开发。

 

2.   导入spring boot的web支持

                 
      
       org.springframework.boot
                  
      
       spring-boot-starter-web
              
     

3.   添加Spring boot的插件

                     
      
       org.springframework.boot
                      
      
       spring-boot-maven-plugin
                  
     

 

最终的pom.xml：

         
      
       4.0.0
          
      
       cn.qiaoliqiang
          
      
       spring-boot
          
      
       0.0.1-SNAPSHOT
          
      
       war
              
              
       
        org.springframework.boot
               
       
        spring-boot-starter-parent
               
       
        1.5.2.RELEASE
           
          
              
                   
        
         org.springframework.boot
                    
        
         spring-boot-starter-web
                
               
                   
        
         org.springframework
                    
        
         spring-webmvc
                    
        
         4.3.7.RELEASE
                
               
               
                   
        
         com.jolbox
                    
        
         bonecp-spring
                    
        
         0.8.0.RELEASE
                
           
          
              
       
        ${project.artifactId}
               
               
                        
         
          org.springframework.boot
                         
         
          spring-boot-maven-plugin
                     
                    
                    
                        
         
          org.apache.maven.plugins
                         
         
          maven-resources-plugin
                         
                             
          
           UTF-8
                          
                     
                    
                    
                        
         
          org.apache.maven.plugins
                         
         
          maven-compiler-plugin
                         
                             
          1.7                    
          
           1.7
                              
          
           UTF-8
                          
                     
                
               
                   
                        
                         
                             
          
           org.apache.tomcat.maven
                              
          
           tomcat7-maven-plugin
                              
          
           2.2
                          
                     
                
           
      
     

4.   编写第一个Spring Boot的应用

@Controller@SpringBootApplication@Configurationpublic class HelloApplication {        @RequestMapping("hello")    @ResponseBody    public String hello(){        return "hello world！";    }        public static void main(String[] args) {        SpringApplication.run(HelloApplication.class, args);    }}

代码说明：

1、@SpringBootApplication：Spring Boot项目的核心注解，主要目的是开启自动配置。；

2、@Configuration：这是一个配置Spring的配置类；

3、@Controller：标明这是一个SpringMVC的Controller控制器；

4、main方法：在main方法中启动一个应用，即：这个应用的入口；

 

5.   启动应用

在Spring Boot项目中，启动的方式有两种，一种是直接run Java Application另外一种是通过Spring Boot的Maven插件运行。

第一种：

 

 结果:

.   ____          _            __ _ _ /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/  ___)| |_)| | | | | || (_| |  ) ) ) )  '  |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot ::        (v1.5.2.RELEASE)2018-01-11 16:54:36.745  INFO 882716 --- [           main] cn.qlq.springboot.HelloApplication       : Starting HelloApplication on root with PID 882716 (E:\MavenEclipseWorkspace\spring-boot\target\classes started by liqiang in E:\MavenEclipseWorkspace\spring-boot)2018-01-11 16:54:36.750  INFO 882716 --- [           main] cn.qlq.springboot.HelloApplication       : No active profile set, falling back to default profiles: default2018-01-11 16:54:36.872  INFO 882716 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@67dd2285: startup date [Thu Jan 11 16:54:36 CST 2018]; root of context hierarchy2018-01-11 16:54:40.517  INFO 882716 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)2018-01-11 16:54:40.678  INFO 882716 --- [           main] o.apache.catalina.core.StandardService   : Starting service Tomcat2018-01-11 16:54:40.680  INFO 882716 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.112018-01-11 16:54:40.998  INFO 882716 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext2018-01-11 16:54:40.999  INFO 882716 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 4131 ms2018-01-11 16:54:41.365  INFO 882716 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]2018-01-11 16:54:41.372  INFO 882716 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]2018-01-11 16:54:41.373  INFO 882716 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]2018-01-11 16:54:41.373  INFO 882716 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]2018-01-11 16:54:41.373  INFO 882716 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]2018-01-11 16:54:42.097  INFO 882716 --- [           main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@67dd2285: startup date [Thu Jan 11 16:54:36 CST 2018]; root of context hierarchy2018-01-11 16:54:42.240  INFO 882716 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/hello]}" onto public java.lang.String cn.qlq.springboot.HelloApplication.hello()2018-01-11 16:54:42.250  INFO 882716 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity
     
      
       > org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)2018-01-11 16:54:42.251  INFO 882716 --- [           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)2018-01-11 16:54:42.351  INFO 882716 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2018-01-11 16:54:42.351  INFO 882716 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2018-01-11 16:54:42.481  INFO 882716 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2018-01-11 16:54:43.241  INFO 882716 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup2018-01-11 16:54:43.414  INFO 882716 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)2018-01-11 16:54:43.429  INFO 882716 --- [           main] cn.qlq.springboot.HelloApplication       : Started HelloApplication in 8.809 seconds (JVM running for 9.52)2018-01-11 17:04:05.722  INFO 882716 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring FrameworkServlet 'dispatcherServlet'2018-01-11 17:04:05.722  INFO 882716 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization started2018-01-11 17:04:05.804  INFO 882716 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization completed in 82 ms
      
     

　　

访问:

 

 

第二种：以spring-boot插件的方式运行:

(1)添加一个maven常用命令

 

 

 

（2）运行上面建的maven命令:

 

 

 

 

 

 

结果与上面一样

 

看到如下信息就说明启动成功了：

2018-01-11 18:01:42.242  INFO 1021040 --- [           main] cn.qlq.springboot.HelloApplication       : Started HelloApplication in 6.845 seconds (JVM running for 16.07)

 

测试: