1整合思路
1、SqlSessionFactory对象应该放到spring容器中作为单例存在。
2、传统dao的开发方式中，应该从spring容器中获得sqlsession对象。
3、Mapper代理形式中，应该从spring容器中直接获得mapper的代理对象。
4、数据库的连接以及数据库连接池事务管理都交给spring容器来完成。
2 需要整合的jar包
1、spring的jar包
2、Mybatis的jar包
3、Spring+mybatis的整合包。
4、Mysql的数据库驱动jar包。
5、数据库连接池的jar包。
3 整合步骤
1.创建java工程
2.导入jar包
3.加入配置文件
1 SqlMapConfig.xml
<?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> <!-- 设置别名 --> <typeAliases> <!-- 2. 指定扫描包，会把包内所有的类都设置别名，别名的名称就是类名，大小写不敏感 --> <package name="cn.itcast.mybatis.pojo" /> </typeAliases> </configuration>
2 applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:p="http://www.springframework.org/schema/p" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd"> <!-- 1加载配置文件 --> <context:property-placeholder location="classpath:db.properties" /> <!-- 2配置连接池 --> <bean name="dataSource" class="org.apache.commons.dbcp.BasicDataSource"> <property name="driverClassName" value="${jdbc.driver}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <property name="maxActive" value="10" /> <property name="maxIdle" value="5" /> </bean> <!--3 配置SqlSessionFactory --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 配置mybatis核心配置文件 --> <property name="configLocation" value="classpath:SqlMapConfig.xml" /> <!-- 配置数据源 --> <property name="dataSource" ref="dataSource" /> </bean> </beans>
3.db.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://39.105.93.154:3306/mybatis?characterEncoding=utf-8
jdbc.username=tom
jdbc.password=tom
4.log4j.properties
### direct log messages to stdout ### log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.Target=System.err log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n ### direct messages to file mylog.log ### log4j.appender.file=org.apache.log4j.FileAppender log4j.appender.file.File=d:\\mylog.log log4j.appender.file.layout=org.apache.log4j.PatternLayout log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n ### set log levels - for more verbose logging change 'info' to 'debug' ### ### fatal error warn info debug trace \u5982\u679C\u4E0D\u60F3\u8981\u8F93\u51FA\uFF1B log4j.rootLogger=off, stdout log4j.rootLogger=debug, stdout
效果
4原始dao的开发方式
原始的DAO开发接口+实现类来完成。
需要dao实现类需要继承SqlsessionDaoSupport类
1需求
- 实现根据用户id查询
- 实现根据用户名模糊查询
- 添加用户
2.创建pojo
package com.mybatis.spring.pojo; import java.io.Serializable; import java.util.Date; import java.util.List; import java.util.Set; public class User implements Serializable { private static final long serialVersionUID = 1L; private Integer id; private String username;// 用户姓名 private Character sex;// 性别 private Date birthday;// 生日 private String address;// 地址 public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public Character getSex() { return sex; } public void setSex(Character sex) { this.sex = sex; } public Date getBirthday() { return birthday; } public void setBirthday(Date birthday) { this.birthday = birthday; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } @Override public String toString() { return "User [id=" + id + ", username=" + username + ", sex=" + sex + ", birthday=" + birthday + ", address=" + address + "]"; } }
3.实现Mapper.xml
编写User.xml配置文件，如下.
这里要注意的是<mapper namespace="test"> 中的 namespace="test" 一定不能掉。
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="test"> <!-- 实现根据用户id查询 --> <select id="queryUserById" parameterType="Integer" resultType="User"> select * from user where id = #{id} </select> <!-- 实现根据用户名模糊查询 --> <select id="queryUserByUsername" parameterType="String" resultType="User"> select * from user where username like '%${value}%' </select> <!-- 添加用户 --> <insert id="saveUser" parameterType="User"> <selectKey keyColumn="id" keyProperty="id" resultType="int" order="AFTER"> select last_insert_id() </selectKey> insert into user (username,birthday,sex,address) values (#{username},#{birthday},#{sex},#{address}) </insert> </mapper>
如果<mapper namespace="test"> 中的 namespace="test" 没有的话，会报下面的异常。
16:56:25,919 WARN ClassPathXmlApplicationContext:487 - Exception encountered during context initialization - cancelling refresh attempt org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [applicationContext.xml]: Invocation of init method failed; nested exception is org.springframework.core.NestedIOException: Failed to parse config resource: class path resource [SqlMapConfig.xml]; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.NullPointerException at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1566) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:743) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480) at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139) at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83) at com.mybatis.spring.junit.UserDaoImplTest.setUp(UserDaoImplTest.java:19) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41) at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:27) at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:263) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:69) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:48) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222) at org.junit.runners.ParentRunner.run(ParentRunner.java:292) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192) Caused by: org.springframework.core.NestedIOException: Failed to parse config resource: class path resource [SqlMapConfig.xml]; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.NullPointerException at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:434) at org.mybatis.spring.SqlSessionFactoryBean.afterPropertiesSet(SqlSessionFactoryBean.java:340) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1625) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1562) ... 35 more Caused by: org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.NullPointerException at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:109) at org.apache.ibatis.builder.xml.XMLConfigBuilder.parse(XMLConfigBuilder.java:92) at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:428) ... 38 more Caused by: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.NullPointerException at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:120) at org.apache.ibatis.builder.xml.XMLMapperBuilder.parse(XMLMapperBuilder.java:92) at org.apache.ibatis.builder.xml.XMLConfigBuilder.mapperElement(XMLConfigBuilder.java:322) at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:107) ... 40 more Caused by: java.lang.NullPointerException at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:109) ... 43 more 16:56:25,921 DEBUG DefaultListableBeanFactory:512 - Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@4098b95b: defining beans [org.springframework.context.support.PropertySourcesPlaceholderConfigurer#0,dataSource,sqlSessionFactory,userDao]; root of factory hierarchy
4.加载Mapper.xml
<?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> <!-- 设置别名 --> <typeAliases> <!-- 2. 指定扫描包，会把包内所有的类都设置别名，别名的名称就是类名，大小写不敏感 --> <package name="com.mybatis.spring.pojo" /> </typeAliases> <mappers> <mapper resource="sqlmap/User.xml"/> <package name="com.mybatis.spring.mapper"/> </mappers> </configuration>
5.实现IUserDao接口
package com.mybatis.spring.dao; import java.util.List; import com.mybatis.spring.pojo.User; public interface IUserDao { public abstract User queryUserById(Integer id); public abstract List<User> queryUserByUsername(String username); public abstract void saveUser(User user); }
6.实现UserDaoImpl实现类
package com.mybatis.spring.dao.impl; import java.util.List; import org.mybatis.spring.support.SqlSessionDaoSupport; import com.mybatis.spring.dao.IUserDao; import com.mybatis.spring.pojo.User; public class UserDaoImpl extends SqlSessionDaoSupport implements IUserDao { /** * 根据id查询用户 */ @Override public User queryUserById(Integer id) { User user = super.getSqlSession().selectOne("queryUserById", id); // 不要关闭sqlSession return user; } /** * 根据用户名模糊查询用户 */ @Override public List<User> queryUserByUsername(String username) { return getSqlSession().selectList("queryUserByUsername", "张"); // 不要关闭sqlSession } /** * 保存用户 */ @Override public void saveUser(User user) { getSqlSession().insert("saveUser",user); // 不要关闭sqlSession } }
7.在applicationContext.xml中配置dao
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:p="http://www.springframework.org/schema/p" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd"> <!-- 1加载配置文件 --> <context:property-placeholder location="classpath:db.properties" /> <!-- 2配置连接池 --> <bean name="dataSource" class="org.apache.commons.dbcp.BasicDataSource"> <property name="driverClassName" value="${jdbc.driver}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <property name="maxActive" value="10" /> <property name="maxIdle" value="5" /> </bean> <!--3 配置SqlSessionFactory --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 配置mybatis核心配置文件 --> <property name="configLocation" value="classpath:SqlMapConfig.xml" /> <!-- 配置数据源 --> <property name="dataSource" ref="dataSource" /> </bean> <!-- 原始开发方式中，配置dao到spring中 --> <bean name="userDao" class="com.mybatis.spring.dao.impl.UserDaoImpl"> <!-- 注入SqlSessionFatory --> <property name="sqlSessionFactory" ref="sqlSessionFactory"></property> </bean> </beans>
8.测试方法
package com.mybatis.spring.junit; import java.util.Date; import java.util.List; import org.junit.Before; import org.junit.Test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import com.mybatis.spring.dao.IUserDao; import com.mybatis.spring.pojo.User; public class UserDaoImplTest { private ApplicationContext ac; @Before public void setUp() throws Exception { this.ac = new ClassPathXmlApplicationContext("classpath:applicationContext.xml"); } @Test public void testQueryUserById() { IUserDao userDao = ac.getBean(IUserDao.class); User user = userDao.queryUserById(25); System.out.println(user); } @Test public void testQueryUserByUsername() { IUserDao userDao = ac.getBean(IUserDao.class); List<User> list = userDao.queryUserByUsername("小"); for (User user : list) { System.out.println(user); } } @Test public void testSaveUser() { IUserDao userDao = ac.getBean(IUserDao.class); User user = new User(); user.setUsername("bobo"); user.setBirthday(new Date()); user.setSex('1'); user.setAddress("湖南"); userDao.saveUser(user); System.out.println(user); } }
5.Mapper代理形式开发dao
a) 直接配置Mapper代理
b) 使用扫描包配置Mapper代理
需求：
- 实现根据用户id查询
- 实现根据用户名模糊查询
- 添加用户
1 实现Mapper.xml
编写UserMapper.xml配置文件，如下：
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.mybatis.spring.mapper.IUserMapper"> <!-- 实现根据用户id查询 --> <select id="queryUserById" parameterType="Integer" resultType="User"> select * from user where id = #{id} </select> <!-- 实现根据用户名模糊查询 --> <select id="queryUserByUsername" parameterType="String" resultType="User"> select * from user where username like '%${value}%' </select> <!-- 添加用户 --> <insert id="saveUser" parameterType="User"> <selectKey keyColumn="id" keyProperty="id" resultType="int" order="AFTER"> select last_insert_id() </selectKey> insert into user (username,birthday,sex,address) values (#{username},#{birthday},#{sex},#{address}) </insert> </mapper>
2.实现UserMapper接口
package com.mybatis.spring.mapper; import java.util.List; import com.mybatis.spring.pojo.User; public interface IUserMapper { public abstract User queryUserById(Integer id); public abstract List<User> queryUserByUsername(String username); public abstract void saveUser(User user); }
3.在applicationContext.xml配置mapper代理-方式一
4 测试程序
package com.mybatis.spring.junit; import java.util.Date; import java.util.List; import org.junit.Before; import org.junit.Test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import com.mybatis.spring.dao.IUserDao; import com.mybatis.spring.mapper.IUserMapper; import com.mybatis.spring.pojo.User; public class IUserMapperTest { private ApplicationContext ac; @Before public void setUp() throws Exception { this.ac = new ClassPathXmlApplicationContext("classpath:applicationContext.xml"); } @Test public void testQueryUserById() { IUserMapper userMapper = ac.getBean(IUserMapper.class); User user = userMapper.queryUserById(31); System.out.println(user); } @Test public void testQueryUserByUsername() { IUserMapper userMapper = ac.getBean(IUserMapper.class); List<User> list = userMapper.queryUserByUsername("小"); for (User user : list) { System.out.println(user); } } @Test public void testSaveUser() { IUserMapper userMapper = ac.getBean(IUserMapper.class); User user = new User(); user.setUsername("youyou"); user.setBirthday(new Date()); user.setSex('1'); user.setAddress("江苏"); userMapper.saveUser(user); System.out.println(user); } }
5.在applicationContext.xml中配置mapper代理方式二
