序言java
在MyBatis學習中,咱們會發現不少重複性的代碼,例如:mysql
//建立鏈接 private SqlSessionFactory sqlSessionFactory = SessionFactoryUtils .getSessionfactory().getSqlSessionFactory(); public void xxx(){ //打開鏈接 sqlSession=sqlSessionFactory.openSession(); //SQL操做開始 //添加 sqlSession.insert("add",user); //更新 sqlSession.update("User.updateById",id); //刪除 sqlSession.delete("User.deleteById",id); //SQL操做結束 //提交數據庫更新 sqlSession.commit(); //關閉鏈接 sqlSession.close(); }
經過代碼咱們能夠看到,建立鏈接、打開鏈接、提交數據庫更新、關閉鏈接這些代碼大量的重複。web
能不能把這些重複的操做經過Spring管理起來,讓開發人員只關注具體的業務操做呢?spring
答案是確定的。sql
經過將Spring 和Mybatis作整合便可。數據庫
整合後的代碼以下所示:apache
@Autowired private SqlSessionTemplate sqlSessionTemplate; public void xxx(){ //添加 sqlSessionTemplate.insert("add",user); //更新 sqlSessionTemplate.update("User.updateById",id); //刪除 sqlSessionTemplate.delete("User.deleteById",id); }
很明顯,整合後的代碼更加的簡潔、高效。api
Spring與MyBatis整合的方式有不少種,本文講述的是使用最簡單的一種,使用SqlSessionTemplate整合。session
SqlSessionTemplate是接口org.apache.ibatis.session.SqlSession的實現類,全名是org.mybatis.spring.SqlSessionTemplate。Mybatis的鏈接能夠由它來進行統一的管理。mybatis
1、Spring與MyBatis整合的步驟
須要導入的Jar包有:
mybatis-spring-1.2.2.jar
commons-pool-1.6.jar
commons-dbcp-1.4.jar
commons-collections-3.2.jar
aspectjweaver-1.8.1.jar
完整的pom.xml內容以下所示:
<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>SpringAndMyBatis</groupId> <artifactId>Integeration</artifactId> <packaging>war</packaging> <version>0.0.1-SNAPSHOT</version> <name>Integeration Maven Webapp</name> <url>http://maven.apache.org</url> <dependencies> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>3.2.7</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.31</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-asm</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>3.0.5.RELEASE</version> </dependency> <!-- end spring 核心依賴包 --> <!-- start spring mvc --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>jstl</artifactId> <version>1.2</version> </dependency> <!-- START SERVLET --> <dependency> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> <version>2.5</version> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>jsp-api</artifactId> <version>2.1</version> <scope>provided</scope> </dependency> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjweaver</artifactId> <version>1.8.1</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>1.2.2</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>commons-pool</groupId> <artifactId>commons-pool</artifactId> <version>1.6</version> </dependency> <dependency> <groupId>commons-dbcp</groupId> <artifactId>commons-dbcp</artifactId> <version>1.4</version> </dependency> <dependency> <groupId>commons-collections</groupId> <artifactId>commons-collections</artifactId> <version>3.2</version> </dependency> </dependencies> <build> <finalName>Integeration</finalName> <sourceDirectory>src/main/java</sourceDirectory> <testSourceDirectory>src/test/java</testSourceDirectory> <resources> <resource> <directory>src/main/java</directory> </resource> </resources> <testResources> <testResource> <directory>src/test/java</directory> </testResource> </testResources> </build> </project>
因爲須要Spring來管理MyBatis的鏈接,所以,與鏈接有關的配置須要從Mybatis遷移至Spring配置文件。
MyBatis的配置文件只剩下以下所示:
<?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> <typeAliases> <typeAlias alias="user" type="com.uni2uni.model.User"/> </typeAliases> <mappers> <mapper resource="com/uni2uni/model/sqlmapper/user.xml" /> </mappers> </configuration>
Spring的配置關鍵代碼以下所示:
<!-- 配置mybitasSqlSessionFactoryBean --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <property name="configLocation" value="classpath:mybatis.xml"></property> </bean> <!-- 配置SqlSessionTemplate --> <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate"> <constructor-arg name="sqlSessionFactory" ref="sqlSessionFactory" /> </bean>
Spring配置文件完整以下所示:
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd"> <!-- 採用註釋的方式配置bean --> <context:annotation-config /> <!-- 配置要掃描的包 --> <context:component-scan base-package="com.uni2uni.*"></context:component-scan> <!--proxy-target-class="true"強制使用cglib代理 若是爲false則spring會自動選擇--> <aop:aspectj-autoproxy proxy-target-class="true"/> <!-- 數據庫配置文件位置 --> <context:property-placeholder location="classpath:jdbc.properties" /> <!-- 配置dbcp數據源 --> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${jdbc.driverClassName}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <!-- 隊列中的最小等待數 --> <property name="minIdle" value="${jdbc.minIdle}"></property> <!-- 隊列中的最大等待數 --> <property name="maxIdle" value="${jdbc.maxIdle}"></property> <!-- 最長等待時間,單位毫秒 --> <property name="maxWait" value="${jdbc.maxWait}"></property> <!-- 最大活躍數 --> <property name="maxActive" value="${jdbc.maxActive}"></property> <property name="initialSize" value="${jdbc.initialSize}"></property> </bean> <!-- 配置mybitasSqlSessionFactoryBean --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <property name="configLocation" value="classpath:mybatis.xml"></property> </bean> <!-- 配置SqlSessionTemplate --> <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate"> <constructor-arg name="sqlSessionFactory" ref="sqlSessionFactory" /> </bean> <!-- 事務配置 --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource" /> </bean> <!-- 使用annotation註解方式配置事務 --> <tx:annotation-driven transaction-manager="transactionManager"/> </beans>
jdbc.properties中的代碼以下所示:
jdbc.driverClassName=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql://localhost:3306/ibatisdatabase jdbc.username=root jdbc.password=root jdbc.maxActive=2 jdbc.maxIdle=5 jdbc.minIdle=1 jdbc.initialSize=3 jdbc.maxWait=3000
數據庫的實現類關鍵代碼以下所示:
@Repository public class UserDaoImpl implements UserDao { @Autowired private SqlSessionTemplate sqlSessionTemplate; public void add(User user) { sqlSessionTemplate.insert("add", user); } }
本例中完整Demo下載:http://pan.baidu.com/s/1hq011Tq
單元測試類在/src/test/java/UserDaoUnit.java類中。
2、知識擴展
(1)Spring與MyBatis整合方式。
Spring與MyBatis整合經常使用的有三種方式:SqlSessionTemplate、SqlSessionDaoSupport、MapperFactoryBean(數據映射器)。
本文采用的是SqlSessionTemplate方式,也是相比其它兩種更簡單的方式。
SqlSessionDaoSupport是一個抽象類,全名爲org.mybatis.spring.support.SqlSessionDaoSupport。使用中須要在實現類中繼承它。
採用MapperFactoryBean(數據映射器)的方式,不用寫mybatis映射文件,採用註解方式提供相應的sql語句和輸入參數。