IntelliJ IDEA搭建SpringBoot应用

　　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。通过这种方式，Boot致力于在蓬勃发展的快速应用开发领域（rapid application development）成为领导者。

使用spring boot有什么好处

其实就是简单、快速、方便！平时如果我们需要搭建一个spring web项目的时候需要怎么做呢？
1）配置web.xml，加载spring和spring mvc
2）配置数据库连接、配置spring事务
3）配置加载配置文件的读取，开启注解
4）配置日志文件
...
配置完成之后部署tomcat 调试
...
现在非常流行微服务，如果我这个项目仅仅只是需要发送一个邮件，如果我的项目仅仅是生产一个积分；我都需要这样折腾一遍!
但是如果使用spring boot呢？
很简单，我仅仅只需要非常少的几个配置就可以迅速方便的搭建起来一套web项目或者是构建一个微服务！ 

1.创建一个新项目(Create New Project)

选择 Spring Initializr，Project SDK 选择 1.8，URL 填写默认的，点击 Next

2.继续项目配置

 

Name：项目名称
Type：我们是Maven构建的，那么选择第一个Maven Project
Packaging：打包类型，打包成Jar文件
Java Version：jdk版本，选择1.8
Language：开发语言，选择Java
Group：对应pom文件中的groupId，项目组织的唯一标识，对应Java包的结构
Artifact：对应pom文件的artifactId，项目唯一标识，对应项目名称
Version：项目版本，对应pom文件的version
Description：项目描述，对应pom文件的description
Package：包名

3.Spring Boot 版本选择，我这里选择了1.5.2，只要勾选Web下的web就可以了，然后Next

4.填写项目名称，项目存放的目录，点击 Finish

 

5.可以将下面这三个无关的文件删除，干净结构

 

6.最后的项目结构

 

这里看一下自动生成的pom.xml文件

<?xml version="1.0" encoding="UTF-8"?><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.example</groupId>    <artifactId>demo</artifactId>    <version>0.0.1-SNAPSHOT</version>    <packaging>jar</packaging>    <name>demo</name>    <description>Demo project for Spring Boot</description>    <parent>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-starter-parent</artifactId>        <version>1.5.2.RELEASE</version>        <relativePath/> <!-- lookup parent from repository -->    </parent>    <properties>        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>        <java.version>1.8</java.version>    </properties>    <dependencies>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-web</artifactId>        </dependency>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-test</artifactId>            <scope>test</scope>        </dependency>    </dependencies>    <build>        <plugins>            <plugin>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-maven-plugin</artifactId>            </plugin>        </plugins>    </build></project>

7.新建一个Controller进行测试

@RestControllerpublic class HelloController {    @RequestMapping(value = "/hello")    public String hello() {        return "hello,Spring Boot";    }}

@RestController的意思就是controller里面的方法都以json格式输出，不用再写什么jackjson配置的了！

整个项目的启动类就是上面的DemoApplication

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

8.启动成功信息，端口8080 

 .   ____          _            __ _ _ /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/  ___)| |_)| | | | | || (_| |  ) ) ) )  '  |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot ::        (v1.5.3.RELEASE)2017-04-24 01:29:17.293  INFO 19480 --- [  restartedMain] com.example.DemoApplication              : Starting DemoApplication on DESKTOP-4U9C0CH with PID 19480 (D:\IdeaProjects\test\demo\target\classes started by winner_0715 in D:\IdeaProjects\test\demo)2017-04-24 01:29:17.295  INFO 19480 --- [  restartedMain] com.example.DemoApplication              : No active profile set, falling back to default profiles: default2017-04-24 01:29:17.432  INFO 19480 --- [  restartedMain] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@1f5f2168: startup date [Mon Apr 24 01:29:17 CST 2017]; root of context hierarchy2017-04-24 01:29:21.450  INFO 19480 --- [  restartedMain] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)2017-04-24 01:29:21.493  INFO 19480 --- [  restartedMain] o.apache.catalina.core.StandardService   : Starting service Tomcat2017-04-24 01:29:21.495  INFO 19480 --- [  restartedMain] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.142017-04-24 01:29:21.820  INFO 19480 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext2017-04-24 01:29:21.820  INFO 19480 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 4396 ms2017-04-24 01:29:22.136  INFO 19480 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]2017-04-24 01:29:22.149  INFO 19480 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]2017-04-24 01:29:22.150  INFO 19480 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]2017-04-24 01:29:22.150  INFO 19480 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]2017-04-24 01:29:22.151  INFO 19480 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]2017-04-24 01:29:22.642  INFO 19480 --- [  restartedMain] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@1f5f2168: startup date [Mon Apr 24 01:29:17 CST 2017]; root of context hierarchy2017-04-24 01:29:22.785  INFO 19480 --- [  restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/index]}" onto public java.util.Map<java.lang.String, java.lang.String> com.example.test.IndexController.test(java.lang.String)2017-04-24 01:29:22.791  INFO 19480 --- [  restartedMain] 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)2017-04-24 01:29:22.792  INFO 19480 --- [  restartedMain] 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)2017-04-24 01:29:22.896  INFO 19480 --- [  restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2017-04-24 01:29:22.896  INFO 19480 --- [  restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2017-04-24 01:29:22.963  INFO 19480 --- [  restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2017-04-24 01:29:23.250  INFO 19480 --- [  restartedMain] o.s.b.d.a.OptionalLiveReloadServer       : LiveReload server is running on port 357292017-04-24 01:29:23.351  INFO 19480 --- [  restartedMain] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup2017-04-24 01:29:23.492  INFO 19480 --- [  restartedMain] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)2017-04-24 01:29:23.507  INFO 19480 --- [  restartedMain] com.example.DemoApplication              : Started DemoApplication in 6.736 seconds (JVM running for 7.717)

9.到浏览器中输入 http://localhost:8080/hello

 

上面讲的打包方式是jar，试了一下war的打包方式，生成的目录结构是这样的