用SpringBoot搭建簡單電商項目 01

前幾節呢，我們已經簡單介紹了SpringBoot框架的使用，從這一節開始，我們嘗試着使用SpringBoot框架來一步一步搭建一個簡單電商項目。當然了，這不是真正的電商項目，你可以看成是一個CRUD案例，只是應用到了SpringBoot框架而已。

開發工具：eclipse 數據庫：MySQL

##1.新建項目

你可以看到選擇的pom文件是報錯的，讓我們打開pom文件一探究竟。

說是缺失了web.xml文件，那么我們手動去添加一下。 在這里新建一個WEB-INF文件夾： 再新建一個web.xml文件：

噢耶，pom文件不報錯啦！

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>java520.top</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
</web-app>

在pom文件中添加上SpringBoot的父依賴：

<parent>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-parent</artifactId>
	<version>1.5.10.RELEASE</version>
	<relativePath/> <!-- lookup parent from repository -->
</parent>

保存，可以看到Maven在自動下載jar包和pom文件了。

再添加上編碼和jdk的配置：

<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.7</java.version>
	</properties>

還有jar包依賴：

<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-data-jpa</artifactId>
		</dependency>
		
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
		</dependency>
		
		
	</dependencies>

插件依賴：

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

在java源文件夾中創建一個啟動類：

代碼：

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class App {

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

運行，發現報錯：

rg.springframework.beans.factory.BeanDefinitionStoreException: Failed to parse configuration class [App]; nested exception is java.io.FileNotFoundException: class path resource [org/springframework/social/config/annotation/SocialConfigurerAdapter.class] cannot be opened because it does not exist
	at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:181) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:308) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:228) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:272) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:92) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:687) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:525) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:693) [spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:360) [spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) [spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1118) [spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1107) [spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
	at App.main(App.java:8) [classes/:na]
Caused by: java.io.FileNotFoundException: class path resource [org/springframework/social/config/annotation/SocialConfigurerAdapter.class] cannot be opened because it does not exist
	at org.springframework.core.io.ClassPathResource.getInputStream(ClassPathResource.java:172) ~[spring-core-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:50) ~[spring-core-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:102) ~[spring-core-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.boot.type.classreading.ConcurrentReferenceCachingMetadataReaderFactory.createMetadataReader(ConcurrentReferenceCachingMetadataReaderFactory.java:89) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
	at org.springframework.boot.type.classreading.ConcurrentReferenceCachingMetadataReaderFactory.getMetadataReader(ConcurrentReferenceCachingMetadataReaderFactory.java:76) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
	at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:80) ~[spring-core-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassParser.asSourceClass(ConfigurationClassParser.java:693) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassParser$SourceClass.getSuperClass(ConfigurationClassParser.java:857) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassParser.doProcessConfigurationClass(ConfigurationClassParser.java:328) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassParser.processConfigurationClass(ConfigurationClassParser.java:245) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:190) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassParser.doProcessConfigurationClass(ConfigurationClassParser.java:292) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassParser.processConfigurationClass(ConfigurationClassParser.java:245) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:198) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:167) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
	... 13 common frames omitted

百度了一下，大概意思好像是不能在默認的包里面啟動，得有一個具體的package。 ok，那我們就給他一個package。

再配上配置文件：

server:
  port: 80
  context-path: /

運行后報錯：

***************************
APPLICATION FAILED TO START
***************************

Description:

Cannot determine embedded database driver class for database type NONE

Action:

If you want an embedded database please put a supported one on the classpath. If you have database settings to be loaded from a particular profile you may need to active it (no profiles are currently active).

大概的意思呢，就是說springboot自動幫我們注入DataSource了，而我們在yml文件里面還並沒有配置數據庫的連接信息，所以就報錯了。

現在，我們完善一下yml文件：

server:
  port: 80
  context-path: /
  
spring:
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/db_shop  
    username: root
    password: 123456
  jpa:
    hibernate:
      ddl-auto: update
      show-sql: true    

數據庫采用我本地的MySQL 再次啟動，終於不報錯了。 現在，新建一個控制器：

測試代碼：

package com.java520.top.shop.controller;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class UserController {
	
	@RequestMapping("/getUserById")
	public String getUserById(){
		return "剽悍一小兔";
	}

}

啟動項目，訪問：http://localhost/getUserById 得：

成功了，至此，我們的項目搭建完畢。

源碼下載地址：http://java520.top/article/2be4eda6-c749-44ad-8f77-fce641b09a08.html

###PS: 更正一個錯誤，已經是SpringBoot項目了，那么打包方式就不需要打成war包了，因為以前做項目都是這樣做的，習慣一下子沒改過來。。。