spring boot 心得

1. 开箱即用

整合常用框架,内嵌tomcat ,直接通过main函数启动. 可打包可执行jar.
我是官网链接
可以看到间接引入的依赖

2. 约定大于配置

基于此省去了 web.xml , spring-config.xml 等繁琐的配置.

2.1 静态文件

如 js代码, 图片等, 默认放在与源文件目录src同级的static/下即可. 如hello.html放在projectDir/static/下, 对应的URL就是http://ip:port/hello.html .

2.2 日志配置

可以写到src/main/resources/log4j.properties中.

3. websocket功能

基础的websocket类编写可参见 websocket (html5新规范)
在spring boot中使用,需要以下3步.

• 需要额外引入依赖

<dependency>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-websocket</artifactId>    <version>${spring-boot.version}</version></dependency>

• 在main()函数所在类上添加@EnableWebSocket注解.
• 新写一个websocket的配置类

import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.web.socket.server.standard.ServerEndpointExporter;@Configurationpublic class EndpointConfig {    @Bean    //MyWebSocket 为自己的WebSocket类.    public MyWebSocket serverendpoint() {        return new MyWebSocket();    }    @Bean    public ServerEndpointExporter endpointExporter() {        return new ServerEndpointExporter();    }}

4.filter功能

与main() 函数所在类同级的配置类.

@Configurationpublic class AConfig {    @Bean    public CrossDomainFilter crossDomainFilter() {        return new CrossDomainFilter();    }}

filter 实现见下:

@WebFilter(urlPatterns = "/2017", filterName = "crossDomainFilter")public class CrossDomainFilter implements Filter {...}

5. 启动日志

贴一段启动日志感受一下.
启动后, 访问localhost:8080 即可出现”Hello World!” 报文.

  .   ____          _            __ _ _ /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/  ___)| |_)| | | | | || (_| |  ) ) ) )  '  |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot ::        (v1.5.1.RELEASE)2017-02-17 14:02:15.891  INFO 5172 --- [           main] c.y.springbootdemo.SampleController      : Starting SampleController on MININT-R287J3I with PID 5172 (C:\Users\yichu.dyc\workspace\csdn\SpringBootDemo\target\classes started by yichu.dyc in C:\Users\yichu.dyc\workspace\csdn\SpringBootDemo)2017-02-17 14:02:15.899  INFO 5172 --- [           main] c.y.springbootdemo.SampleController      : No active profile set, falling back to default profiles: default2017-02-17 14:02:15.976  INFO 5172 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@43d7741f: startup date [Fri Feb 17 14:02:15 CST 2017]; root of context hierarchy2017-02-17 14:02:17.546  INFO 5172 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.boot.autoconfigure.validation.ValidationAutoConfiguration' of type [class org.springframework.boot.autoconfigure.validation.ValidationAutoConfiguration] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)2017-02-17 14:02:17.661  INFO 5172 --- [           main] trationDelegate$BeanPostProcessorChecker : Bean 'validator' of type [class org.springframework.validation.beanvalidation.LocalValidatorFactoryBean] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)2017-02-17 14:02:18.602  INFO 5172 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)2017-02-17 14:02:18.631  INFO 5172 --- [           main] o.apache.catalina.core.StandardService   : Starting service Tomcat2017-02-17 14:02:18.633  INFO 5172 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.112017-02-17 14:02:18.810  INFO 5172 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext2017-02-17 14:02:18.810  INFO 5172 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 2840 ms2017-02-17 14:02:19.082  INFO 5172 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]2017-02-17 14:02:19.088  INFO 5172 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]2017-02-17 14:02:19.088  INFO 5172 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]2017-02-17 14:02:19.089  INFO 5172 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]2017-02-17 14:02:19.089  INFO 5172 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]2017-02-17 14:02:19.506  INFO 5172 --- [           main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@43d7741f: startup date [Fri Feb 17 14:02:15 CST 2017]; root of context hierarchy2017-02-17 14:02:19.609  INFO 5172 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/]}" onto java.lang.String com.yichudu.springbootdemo.SampleController.home()2017-02-17 14:02:19.613  INFO 5172 --- [           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)2017-02-17 14:02:19.615  INFO 5172 --- [           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)2017-02-17 14:02:19.654  INFO 5172 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2017-02-17 14:02:19.654  INFO 5172 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2017-02-17 14:02:19.708  INFO 5172 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2017-02-17 14:02:19.909  INFO 5172 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup2017-02-17 14:02:20.030  INFO 5172 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)2017-02-17 14:02:20.037  INFO 5172 --- [           main] c.y.springbootdemo.SampleController      : Started SampleController in 4.639 seconds (JVM running for 5.304)2017-02-17 14:06:17.386  INFO 5172 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring FrameworkServlet 'dispatcherServlet'2017-02-17 14:06:17.387  INFO 5172 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization started2017-02-17 14:06:17.434  INFO 5172 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization completed in 47 ms