Spring Boot是由Pivotal团队提供的全新框架，其设计目的是用来简化新Spring应用的初始搭建以及开发过程。该框架使用了特定的方式来进行配置，从而使开发人员不再需要定义样板化的配置
Spring Boot有以下特点：
1. 创建独立的Spring应用程序
2. 嵌入的Tomcat，无需部署WAR文件
3. 简化Maven配置
4. 自动配置Spring
5. 提供生产就绪型功能，如指标，健康检查和外部配置
6. 绝对没有代码生成和对XML没有要求配置
下面是Spring Boot的Maven配置：
1 <?xml version="1.0" encoding="UTF-8"?> 2 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 3 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> 4 <modelVersion>4.0.0</modelVersion> 5 6 <groupId>com.mytest</groupId> 7 <artifactId>springboot</artifactId> 8 <version>0.0.1-SNAPSHOT</version> 9 <packaging>jar</packaging> 10 11 <name>springboot</name> 12 <description>Demo project for Spring Boot</description> 13 14 <parent> 15 <groupId>org.springframework.boot</groupId> 16 <artifactId>spring-boot-starter-parent</artifactId> 17 <version>1.5.9.RELEASE</version> 18 <relativePath /> <!-- lookup parent from repository --> 19 </parent> 20 21 <properties> 22 <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> 23 <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> 24 <java.version>1.8</java.version> 25 </properties> 26 27 <dependencies> 28 <dependency> 29 <groupId>org.springframework.boot</groupId> 30 <artifactId>spring-boot-starter-web</artifactId> 31 </dependency> 32 33 <dependency> 34 <groupId>org.springframework.boot</groupId> 35 <artifactId>spring-boot-starter-test</artifactId> 36 <scope>test</scope> 37 </dependency> 38 </dependencies> 39 40 <build> 41 <plugins> 42 <plugin> 43 <groupId>org.springframework.boot</groupId> 44 <artifactId>spring-boot-maven-plugin</artifactId> 45 </plugin> 46 </plugins> 47 </build> 48 </project>
Java代码启动：
1 package com.mytest.springboot; 2 3 import org.springframework.boot.SpringApplication; 4 import org.springframework.boot.autoconfigure.EnableAutoConfiguration; 5 import org.springframework.web.bind.annotation.RequestMapping; 6 import org.springframework.web.bind.annotation.RestController; 7 8 /** 9 * (1)@RestController<br> 10 * 相当于@[email protected]。<br> 11 * 如果只是使用@RestController，则Controller中的方法无法返回return对应的jsp页面，配置的视图解析器InternalResourceViewResolver不起作用，返回的内容就是return里的内容。<br> 12 * 如果需要返回到指定页面，则需要用@Controller配合视图解析器InternalResourceViewResolver才行。<br> 13 * 如果需要返回JSON，XML或自定义mediaType内容到页面，则需要在对应的方法上加上@ResponseBody注解。<br> 14 * (2)@EnableAutoConfiguration<br> 15 * 这个注释告诉SpringBoot“猜”你将如何想配置Spring,基于你已经添加jar依赖项。如果spring-boot-starter-web已经添加Tomcat和Spring MVC,这个注释自动将假设您正在开发一个web应用程序并添加相应的spring设置。<br> 16 */ 17 @RestController 18 @EnableAutoConfiguration 19 public class SpringbootApplication { 20 21 @RequestMapping("/") 22 String home() { 23 return "Hello World!"; 24 } 25 26 public static void main(String[] args) { 27 SpringApplication.run(SpringbootApplication.class, args); 28 } 29 }
启动log：
1 . ____ _ __ _ _ 2 /\\ / ___‘_ __ _ _(_)_ __ __ _ \ \ \ \ 3 ( ( )\___ | ‘_ | ‘_| | ‘_ \/ _` | \ \ \ \ 4 \\/ ___)| |_)| | | | | || (_| | ) ) ) ) 5 ‘ |____| .__|_| |_|_| |_\__, | / / / / 6 =========|_|==============|___/=/_/_/_/ 7 :: Spring Boot :: (v1.5.9.RELEASE) 8 9 2018-01-26 05:09:34.615 INFO 9788 --- [ main] c.m.springboot.SpringbootApplication : Starting SpringbootApplication on GCOTVMSW725771 with PID 9788 (C:\workspace_utils\springboot\target\classes started by yl58731 in C:\workspace_utils\springboot) 10 2018-01-26 05:09:34.619 INFO 9788 --- [ main] c.m.springboot.SpringbootApplication : No active profile set, falling back to default profiles: default 11 2018-01-26 05:09:34.680 INFO 9788 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot[email protected]133e16fd: startup date [Fri Jan 26 05:09:34 EST 2018]; root of context hierarchy 12 2018-01-26 05:09:36.898 INFO 9788 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http) 13 2018-01-26 05:09:36.915 INFO 9788 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat] 14 2018-01-26 05:09:36.917 INFO 9788 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.23 15 2018-01-26 05:09:37.108 INFO 9788 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext 16 2018-01-26 05:09:37.108 INFO 9788 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 2430 ms 17 2018-01-26 05:09:37.352 INFO 9788 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: ‘dispatcherServlet‘ to [/] 18 2018-01-26 05:09:37.355 INFO 9788 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: ‘characterEncodingFilter‘ to: [/*] 19 2018-01-26 05:09:37.356 INFO 9788 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: ‘hiddenHttpMethodFilter‘ to: [/*] 20 2018-01-26 05:09:37.356 INFO 9788 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: ‘httpPutFormContentFilter‘ to: [/*] 21 2018-01-26 05:09:37.356 INFO 9788 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: ‘requestContextFilter‘ to: [/*] 22 2018-01-26 05:09:37.770 INFO 9788 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot[email protected]133e16fd: startup date [Fri Jan 26 05:09:34 EST 2018]; root of context hierarchy 23 2018-01-26 05:09:37.854 INFO 9788 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/]}" onto java.lang.String com.mytest.springboot.SpringbootApplication.home() 24 2018-01-26 05:09:37.857 INFO 9788 --- [ 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) 25 2018-01-26 05:09:37.858 INFO 9788 --- [ 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) 26 2018-01-26 05:09:37.896 INFO 9788 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 27 2018-01-26 05:09:37.897 INFO 9788 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 28 2018-01-26 05:09:37.947 INFO 9788 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 29 2018-01-26 05:09:38.133 INFO 9788 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup 30 2018-01-26 05:09:38.354 INFO 9788 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http) 31 2018-01-26 05:09:38.361 INFO 9788 --- [ main] c.m.springboot.SpringbootApplication : Started SpringbootApplication in 4.186 seconds (JVM running for 4.71) 32 2018-01-26 05:09:39.865 INFO 9788 --- [nio-8080-exec-2] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring FrameworkServlet ‘dispatcherServlet‘ 33 2018-01-26 05:09:39.866 INFO 9788 --- [nio-8080-exec-2] o.s.web.servlet.DispatcherServlet : FrameworkServlet ‘dispatcherServlet‘: initialization started 34 2018-01-26 05:09:39.893 INFO 9788 --- [nio-8080-exec-2] o.s.web.servlet.DispatcherServlet : FrameworkServlet ‘dispatcherServlet‘: initialization completed in 26 ms
打开localhost:8080/即可看到"Hello world!"页面。