SpringBoot第一个示例

start.spring.io导出示例，竟然发现妹的跑不起来。

参考过逃离沙漠 的博客，添加了

<dependency>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-web</artifactId></dependency>

在主文件添加了

@RequestMapping("/hello")    @ResponseBody    String home() {        return "Hello ,spring boot!";    }

具体看他的示例就可以，启动正常。

localhost:8080/hello访问正常，那么说明官方示例是正常的。

启动信息如下，就自动停止了，也没报错。

  .   ____          _            __ _ _ /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/  ___)| |_)| | | | | || (_| |  ) ) ) )  '  |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot ::        (v1.5.9.RELEASE)2017-12-23 23:50:04.031  INFO 6292 --- [           main] c.c.c.s.SpringbootDemoApplication        : Starting SpringbootDemoApplication on Jesse-PC with PID 6292 (D:\workspace-eclipse\springboot-demo\target\classes started by acer in D:\workspace-eclipse\springboot-demo)2017-12-23 23:50:04.031  INFO 6292 --- [           main] c.c.c.s.SpringbootDemoApplication        : No active profile set, falling back to default profiles: default2017-12-23 23:50:04.126  INFO 6292 --- [           main] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@5c18298f: startup date [Sat Dec 23 23:50:04 CST 2017]; root of context hierarchy2017-12-23 23:50:04.921  INFO 6292 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup2017-12-23 23:50:04.937  INFO 6292 --- [           main] c.c.c.s.SpringbootDemoApplication        : Started SpringbootDemoApplication in 1.28 seconds (JVM running for 1.864)2017-12-23 23:50:04.937  INFO 6292 --- [       Thread-2] s.c.a.AnnotationConfigApplicationContext : Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@5c18298f: startup date [Sat Dec 23 23:50:04 CST 2017]; root of context hierarchy2017-12-23 23:50:04.937  INFO 6292 --- [       Thread-2] o.s.j.e.a.AnnotationMBeanExporter        : Unregistering JMX-exposed beans on shutdown

但可以看到第一行：Starting SpringbootDemoApplication on Jesse-PC with PID 6292 (D:\workspace-eclipse\springboot-demo\target\classes started by acer in D:\workspace-eclipse\springboot-demo)

狗日的跑到了target/class下去读取SpringbootDemoApplication，导进来的项目target目录下是空的，那就按套路来打包吧。

项目右键Run As/Maven Build...  

Base directory为${project_loc:springboot-demo} 其中springboot-demo为项目名称。

Goals为package或者clean package -Dmaven.test.skip=true均可，只是前者会多generated-tesrt-sources和surefire-reports，具体

打包好后，刷新项目，target目录下为打包生成的文件

发现target下还是没有class目录呀，那就姑且不管，直接运行jar包启动项目吧。

java -jar springboot-demo-0.0.1-SNAPSHOT.jar > log.file 2>&1 &
访问localhost:8080，页面一闪而过。在target下生成的log.file可以看到启动信息，如上只是到springboot-demo-0.0.1-SNAPSHOT.jar里去读取文件了。
（发现了个有趣的事情是，在eclipse中target下没有class目录，而在工作空间的该项目target下是有class目录的。/无语。）

实际还是跟上面一样，启动后自动熄火了。
在写这篇文章前是在cmd下启动，发现eclipse下项目启动了，当时莫名其妙的，我实在cmd下的控制台直接启动的jar包啊。

最后发现pom.xml中加上

<dependency>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-web</artifactId> </dependency>

可在eclipse运行SpringbootDemoApplication启动项目。http://localhost:8080/报404，加个返回结果就好了。

至此SpringBoot的第一个例子也算是跑起来了。跑步起来的原因肯定是由于@SpringBootApplication注解的特殊性，暂时就不深入了解了。

最终pom.xml如下：

<?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.chensan.cdss</groupId><artifactId>springboot-demo</artifactId><version>0.0.1-SNAPSHOT</version><packaging>jar</packaging><name>springboot-demo</name><description>Demo project for Spring Boot</description><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>1.5.9.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</artifactId></dependency><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>

主文件：

package com.chensan.cdss.springbootdemo;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.ResponseBody;@Controller@SpringBootApplicationpublic class SpringbootDemoApplication {@RequestMapping("/hello")    @ResponseBody    String home() {        return "Hello ,spring boot!";    }public static void main(String[] args) {SpringApplication.run(SpringbootDemoApplication.class, args);}}

访问：http://localhost:8080/hello 效果如下