参数查询与模糊查询

• 使用userMapper.xml中<select>标签的parameterType参数可以实现sql语句的预赋值，防止sql注入

参数查询

• UsersMapper.java

public interface UsersMapper {

public Users getUserListById(int id);

}

• UsersMapper.xml

<?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">

<!-- 为这个mapper指定一个唯一的namespace，namespace的值习惯上设置成包名+sql映射文件名，这样就能够保证namespace的值是唯一的

<mapper namespace="com.mybatis.dao.UsersMapper">

<select id="getUserById" parameterType="int" resultType="Users">
        select * from smbms_user where id=#{id}
</select>

…

</mapper>

• Test.java

@Test

public void testGetUserList() {

SqlSession sqlSession=null;

try{

sqlSession=MyBatisUtil.createSqlSession();

Users user=sqlSession.getMapper(UsersMapper.class).getUserById();

logger.debug("UserMappingTest count--->"+user.getUserName());

sqlSession.commit();

}catch(Exception e){

e.printStackTrace();

}finally{

MyBatisUtil.closeSqlSession(sqlSession);

}

}

模糊查询

• UsersMapper.java

public interface UsersMapper {

public List<Users> getUserListByUserName(String userName);

}

• UsersMapper.xml

<?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">

<!-- 为这个mapper指定一个唯一的namespace，namespace的值习惯上设置成包名+sql映射文件名，这样就能够保证namespace的值是唯一的

<mapper namespace="com.mybatis.dao.UsersMapper">

<select id="getUserList" parameterType="String" resultType="Users">

select * from smbms_user where userName like CONCAT('%',#{userName},'%')

 </select>

…

</mapper>

• Test.java

@Test

public void testGetUserList() {

SqlSession sqlSession=null;

List<Users> userList =new ArrayList<Users>();

try{

sqlSession=MyBatisUtil.createSqlSession();

userList=sqlSession.getMapper(UsersMapper.class).getUserListByUser("张");

}catch(Exception e){

e.printStackTrace();

}finally{

MyBatisUtil.closeSqlSession(sqlSession);

}

for(Users user:userList) {

System.out.println(user.getUserName());

}

}