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: default
2017-12-23 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 hierarchy
2017-12-23 23:50:04.921  INFO 6292 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup
2017-12-23 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 hierarchy
2017-12-23 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
@SpringBootApplication
public 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