IDEA SpringMVC整合mybatis教程
目前Spring整合mybatis的教程,都比較混雜,很難找到零基礎入門文章,而且很多教程例項涉及的內容很多,工程配置複雜,很難讓新手跟著做完,可以執行的專案。也是 因為時間緊,沒有去mybatis官網看文件,一天多時間找的中文的部落格,發現部分部落格例項都比較老,spring和mybatis的版本是一個問題,還有就是開發工具的不一致,MyEclipse、Eclipse EE、IntelliJ IDEA什麼樣的都有,這裡建議在學習這些框架時首先確定一下開發工具,再找相對應的教程,會讓你省去很多時間。
Mybatis最大的特點是:只需要寫好 針對實體類對映資料庫表的介面,不需要寫介面的實現,mybatis動態完成介面的實現。
Mybatis完成java實體類和資料庫表的ORM對映,主要有兩種方式,一種是基於註解的,上面的Spring boot整合mybatis就是這種方式;另外一種是基於XXXMaper.xml,用xml檔案裝配sql,mybatis動態實現介面的Impl,自動載入到Spring IoC容器,controller在需要時即可Autowired,本教程就是用第二種方式,實現最簡單的User實體類與資料庫表的對映,完成增刪改查。
兩種方式共同點:sql語句需要程式設計師來寫,對sql書寫有一定的要求。但是同時,也發揮了sql靈活性的價值。第一種sql寫在註解中,對於簡單操作很容易實現,第二種xml中直接寫sql語句,更能勝任複雜的sql查詢等操作。
注意事項:工程的配置檔案xml,檔案最上面都是有dtd規範的、以及xml版本資訊,在看別人教程的時候,xml配置檔案頭部的dtd,儘量和教程保持一致。有很對教程沒有貼這部分內容,讓後者踩了很多坑。
本教程工具
JDK環境為1.8
maven版本為maven3
Mysql版本為5.5.27
Tomcat版本為8.5
目標
完成基本的SpringMVC + Spring + MyBatis框架整合(簡單例項:完成User實體類的增刪改查)
資料庫使用mysql
加入c3p0資料庫連線池
maven依賴的版本管理
一、SSM框架整合配置
1、使用idea的maven建立一個基本的web工程,即maven-archetype-webapp
提示:IDEA最好設定阿里映象,自行參考http://blog.csdn.net/a1b2c3d4123456/article/details/53915056
2、整理專案檔案組織結構.
配置目錄:
(1)建立main目錄下的java目錄(用於存放java原始碼)
右鍵點選main目錄,接著選中New→Directory,在彈出的對話方塊中輸入java
右鍵點選java,然後選擇Mark Directory As→Sources Root
(2)在resources目錄下新建mapper和spring目錄
右鍵點選resources目錄,接著選中New→Directory,在彈出的對話方塊中輸入mapper。Spring類似。
3、新增pom.xml依賴
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.test</groupId>
<artifactId>seckill</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>seckill Maven Webapp</name>
<url>http://maven.apache.org</url>
<properties>
<java.version>1.8</java.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<!--lib setting-->
<spring.version>4.3.3.RELEASE</spring.version>
<jackson.version>2.6.3</jackson.version>
</properties>
<dependencies>
<!-- config junit jar -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.39</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.1.1</version>
</dependency>
<!-- DAO框架:mybatis-->
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.1</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.3.0</version>
</dependency>
<!-- servlet 相關依賴-->
<dependency>
<groupId>taglibs</groupId>
<artifactId>standard</artifactId>
<version>1.1.2</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.6.7</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
</dependency>
<!--spring依賴-->
<!--1)核心依賴-->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring.version}</version>
</dependency>
<!--2)spring DAO-->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>${spring.version}</version>
</dependency>
<!--3)spring web-->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
<!--4)spring test-->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>${spring.version}</version>
</dependency>
</dependencies>
<build>
<finalName>seckill</finalName>
</build>
</project>
4、新增資料庫設定jdbc.properties
在resources目錄下新建jdbc.properties,配置資訊如下:
driver=com.mysql.jdbc.Driver
url=jdbc:mysql://172.18.81.146:3306/test
username=lee
password=lee
idleConnectionTestPeriod=60
maxIdleTime=240
acquireIncrement=5
initialPoolSize=10
maxPoolSize=30
minPoolSize=10
autoCommitOnClose=false
checkoutTimeout=1000
acquireRetryAttempts=2
User實體類對應的資料庫表:
SET FOREIGN_KEY_CHECKS=0;
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`appid` varchar(255) DEFAULT NULL,
`name` varchar(255) DEFAULT NULL,
`passwd` varchar(255) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8;
5、新增mybatis全域性設定mybatis-config.xml
在resources目錄下新建mybatis-config.xml,配置資訊如下:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!-- mybatis全域性設定 -->
<settings>
<!--使用資料庫自增id-->
<setting name="useGeneratedKeys" value="true" />
<setting name="useColumnLabel" value="true" />
<!-- 開啟駝峰命名規範-->
<setting name="mapUnderscoreToCamelCase" value="true" />
</settings>
</configuration>
6、新增資料庫設定spring-dao.xml
在 resources/spring下新建spring-dao.xml,配置資訊如下:
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:classpath="http://www.springframework.org/schema/c"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">
<!-- 啟動SpringMVC的註解功能,它會自動註冊HandlerMapping、HandlerAdapter、ExceptionResolver的相-->
<mvc:annotation-driven />
<mvc:default-servlet-handler />
<!--掃描,Controller類-->
<context:component-scan base-package="com.test"/>
<context:property-placeholder location="classpath:jdbc.properties"/>
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close"
p:driverClass="${driver}"
p:jdbcUrl="${url}"
p:user="${username}"
p:password="${password}"
p:idleConnectionTestPeriod="${idleConnectionTestPeriod}"
p:maxIdleTime="${maxIdleTime}"
p:acquireIncrement="${acquireIncrement}"
p:initialPoolSize="${initialPoolSize}"
p:maxPoolSize="${maxPoolSize}"
p:minPoolSize="${minPoolSize}"
p:autoCommitOnClose="${autoCommitOnClose}"
p:checkoutTimeout="${checkoutTimeout}"
p:acquireRetryAttempts="${acquireRetryAttempts}"
p:preferredTestQuery="SELECT 1"
p:maxConnectionAge="3000"/>
<!-- mybatis檔案配置,掃描所有mapper檔案 -->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="configLocation" value="classpath:mybatis-config.xml"/>
<property name="typeAliasesPackage" value="com.test.entity"/>
<property name="mapperLocations" value="classpath:mapper/*.xml"/>
</bean>
<!-- spring與mybatis整合配置,掃描所有dao,指定的對映器類是介面,介面方法可以用註解來指定 SQL 語句,但是 MyBatis 的對映器 XML 檔案也可以用。 -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"
p:basePackage="com.test.dao"
p:sqlSessionFactoryBeanName="sqlSessionFactory"/>
</beans>
7、修改webapp\WEB-INF\web.xml,資訊如下:
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
version="3.1"
metadata-complete="true">
<!-- 配置Spring配置檔案路徑 -->
<servlet>
<servlet-name>SpringMVC</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring/spring-dao.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>SpringMVC</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<filter>
<filter-name>encodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>utf-8</param-value>
</init-param>
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encodingFilter</filter-name>
<servlet-name>SpringMVC</servlet-name>
</filter-mapping>
</web-app>
二、實體對映
第一部分,完成了骨架工程和框架的配置。下面增加實體類、操作實體類的介面,完成增刪改查。
1、建立User.java
右鍵java,建立一個package,例如com.test。右鍵com.test建立三個包entity、dao、controller。
分別在entity、dao、controller建立User.java、UserDao.java、UserController.java。
User.java
package com.test.entity;
/**
* 實體類:屬性對應資料庫表的欄位
*/
public class User {
private Integer id;
private String name;
private String passwd;
private String appid;
public User(Integer id , String name, String passwd, String appid) {
this.id = id;
this.name = name;
this.passwd = passwd;
this.appid = appid;
}
public User(String name, String passwd, String appid) {
this.name = name;
this.passwd = passwd;
this.appid = appid;
}
public User(String name, String passwd) {
this.name = name;
this.passwd = passwd;
}
public User() {
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPasswd() {
return passwd;
}
public void setPasswd(String passwd) {
this.passwd = passwd;
}
public String getAppid() {
return appid;
}
public void setAppid(String appid) {
this.appid = appid;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", name='" + name + '\'' +
", passwd='" + passwd + '\'' +
", appid='" + appid + '\'' +
'}';
}
}
UserDao.java
package com.test.dao;
import com.test.entity.User;
/**
* DAO介面,mybatis動態完成Impl
*/
public interface UserDao {
Integer addUser(User u);
User findByAppid(String appid);
User findById(Integer id);
Integer deleteById(Integer id);
}
2、建立Controller
UserController.java
package com.test.controller;
import com.test.dao.UserDao;
import com.test.entity.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
@RestController
@RequestMapping(value = "/test")
public class UserController {
@Autowired(required = false)
private UserDao userDao;
@RequestMapping(value ="/phone", method = RequestMethod.GET)
public User test(){
return userDao.findByAppid("10524782571");
}
//-http://localhost:8080/test/add?name=abc&passwd=123&appid=95955542783
@RequestMapping(value = "/add", method = RequestMethod.GET)
public User save(@RequestParam("name") String name,
@RequestParam(value = "passwd",defaultValue = "0") String passwd,
@RequestParam(value = "appid",defaultValue = "0") String appid) {
User user = new User(name,passwd,appid);
userDao.addUser(user);
return userDao.findById(user.getId());
}
@RequestMapping(value = "/delete", method = RequestMethod.GET)
public void delete(@RequestParam("id") Integer id) {
userDao.deleteById(id);
}
}
最後的工程結構如下圖:
測試:
通過瀏覽器輸入
http://localhost:8080/test/add?name=abc&passwd=123&appid=95955542783
插入資料庫,返回物件的json格式。
網上Spring整合mybatis的文章很雜亂,這兩篇推薦一下:
MyBatis獲取資料庫自生成的主鍵Id詳解
http://www.jb51.net/article/112942.htm