SpringBoot | 项目搭建（踩雷）

一、神器代手

http://start.spring.io/

二、动手丰衣足食

1、在IDEA中创建一个quickstart的Maven项目

groupId==》/src/main/java下的包名字

artifactId==》项目名字





2、引入pom依赖

<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.recruitsys</groupId>
<artifactId>springboot</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>

<name>spring-boot</name>
<url>http://maven.apache.org</url>

<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>

<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.0.RELEASE</version>
<relativePath></relativePath>
</parent>

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

<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>

<repositories>
</repositories>
</project>

这里出现了很大的问题，比如：依赖冲突

解决方法如下

（1）mvn dependency：tree -Dverbose分析后逐个排除依赖冲突

（2）

3、编写启动类

package com.recruitsys;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.RestController;

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

（1）在启动类加上@SpringBootApplication注解

（2）注意启动类的位置必须放在groupId包的下面，否则访问url时会报错误

错误说明：http://blog.csdn.net/q12344566789/article/details/53641582

Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Wed Dec 14 16:35:25 CST 2016
There was an unexpected error (type=Not Found, status=404).
No message available

我当时是因为把“controller”包放在了和“recruitsys”包同级，所以引发了错误。

可见Spring默认大于配置

4、编写控制器

@RestController
public class HelloController {
@RequestMapping("/halo")
public String halo() {
return "halo";
}
}

5、启动、填写URL