spring boot实战(第一篇)第一个案例
2015-08-25 23:29
363 查看
spring boot实战(第一篇)第一个案例
前言
写在前面的话
一直想将spring boot相关内容写成一个系列的博客,今天终于有时间开始了第一篇文章 以后有时间就会继续写下去。
spring boot 博客内容规划
spring boot 基本用法自动配置
技术集成
性能监控
源码解析
spring boot功能强大,后面会细细道来。
第一个案例
工程的构建
构建spring boot工程一般采用两种方式 gradle 、maven;相对于maven的pom配置gradle 更加简单,有兴趣的同学可以去学习下gradle,这里采用maven。
创建一个maven工程,对应的
pom.xml文件:
<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.2.4.RELEASE</version> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build>
版本采用
1.2.4,非官网最新版,但属于稳定版本
创建
Application.java
package com.u51.lkl.springboot; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); } }
运行main方法
. ____ _ __ _ _ /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \ ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v1.2.4.RELEASE) 2015-08-25 22:53:35.484 INFO 554 --- [ main] com.u51.lkl.springboot.Application : Starting Application on mac.local with PID 554 (/Users/liaokailin/code/github/blog-springboot/target/classes started by lkl in /Users/liaokailin/code/github/blog-springboot) 2015-08-25 22:53:35.561 INFO 554 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@328908cd: startup date [Tue Aug 25 22:53:35 CST 2015]; root of context hierarchy 2015-08-25 22:53:36.395 INFO 554 --- [ main] o.s.b.f.s.DefaultListableBeanFactory : Overriding bean definition for bean 'beanNameViewResolver': replacing [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration$WhitelabelErrorViewConfiguration; factoryMethodName=beanNameViewResolver; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/autoconfigure/web/ErrorMvcAutoConfiguration$WhitelabelErrorViewConfiguration.class]] with [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter; factoryMethodName=beanNameViewResolver; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/autoconfigure/web/WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter.class]] 2015-08-25 22:53:37.404 INFO 554 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http) 2015-08-25 22:53:37.796 INFO 554 --- [ main] o.apache.catalina.core.StandardService : Starting service Tomcat 2015-08-25 22:53:37.798 INFO 554 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.0.23 2015-08-25 22:53:37.955 INFO 554 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext 2015-08-25 22:53:37.955 INFO 554 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 2397 ms 2015-08-25 22:53:38.813 INFO 554 --- [ost-startStop-1] o.s.b.c.e.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/] 2015-08-25 22:53:38.818 INFO 554 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*] 2015-08-25 22:53:38.819 INFO 554 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*] 2015-08-25 22:53:39.075 INFO 554 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@328908cd: startup date [Tue Aug 25 22:53:35 CST 2015]; root of context hierarchy 2015-08-25 22:53:39.151 INFO 554 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],methods=[],params=[],headers=[],consumes=[],produces=[],custom=[]}" 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) 2015-08-25 22:53:39.151 INFO 554 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],methods=[],params=[],headers=[],consumes=[],produces=[text/html],custom=[]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest) 2015-08-25 22:53:39.180 INFO 554 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 2015-08-25 22:53:39.180 INFO 554 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 2015-08-25 22:53:39.232 INFO 554 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler] 2015-08-25 22:53:39.326 INFO 554 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup 2015-08-25 22:53:39.430 INFO 554 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http) 2015-08-25 22:53:39.433 INFO 554 --- [ main] com.u51.lkl.springboot.Application : Started Application in 4.829 seconds (JVM running for 5.238)
spring boot已经启动,内嵌
tomcat容器,监听为
8080端口
就是这么简单,一个spring boot 的程序就创建了。
@SpringBootApplication 注解
SpringBootApplication注解源码如下:@Target(ElementType.TYPE) @Retention(RetentionPolicy.RUNTIME) @Documented @Inherited @Configuration @EnableAutoConfiguration @ComponentScan public @interface SpringBootApplication { /** * Exclude specific auto-configuration classes such that they will never be applied. * @return the classes to exclude */ Class<?>[] exclude() default {}; }
@Configuration: 表示
Application作为sprig配置文件存在
@EnableAutoConfiguration: 启动spring boot内置的自动配置
@ComponentScan: 扫描bean,路径为
Application类所在
package以及
package下的子路径,这里为
com.u51.lkl.springboot,在
spring boot中bean都放置在该路径已经子路径下。
构建REST工程
上面的操作连个HelloWorld都没有出来,远远满不足我们的需求。创建一个package:
com.u51.lkl.springboot.controller保存
controller
构建
HelloWorldController.java
package com.u51.lkl.springboot.controller; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.ResponseBody; import org.springframework.web.bind.annotation.RestController; @RestController @RequestMapping("/springboot") public class HelloWorldController { @RequestMapping(value = "/{name}", method = RequestMethod.GET) @ResponseBody public String sayWorld(@PathVariable("name") String name) { return "Hello " + name; } }
再次执行
Application然后访问http://localhost:8080/springboot/Liaokailin
得到结果:
Hello Liaokailin
方法中涉及的注解就不解释了,比较简单~
第一个案例就到这里。
相关文章推荐
- Spring MVC中的DispatcherServlet作用
- 【java关键字-Thread】Thread.Join()的用法,及其实现线程顺序执行的原理
- java新手笔记34 连接数据库
- Java中加载图片方法
- Java弱点
- Java中的Atomic包使用指南
- Java Exception异常介绍
- Java对象、Json、Xml转换工具Jackson使用
- Java对象、Json、Xml转换工具Jackson使用
- Java对象、Json、Xml转换工具Jackson使用
- Java IO流->处理流->缓冲流->字节流&字符流
- Google Java编程风格指南
- Easyui+Spring+Mybatis完整示例(前台)
- spring boot demo(spring jdbc访问数据)
- Java 基础:变量 与 字符串
- JAVA并发编程6_线程协作/生产者-消费者
- JAVA并发编程6_线程协作/生产者-消费者
- JavaSE复习日记 : java包机制
- java.util.ConcurrentModificationException异常
- javadoc中文档注释标记的使用