输入参数可以有三种：简单类型，POJO，包装类
关于前两种：
http://www.cnblogs.com/xuyiqing/p/8600888.html
这里写一下传递包装类参数：
一个POJO：User
package pojo; import java.io.Serializable;
import java.util.Date; public class User implements Serializable {
private static final long serialVersionUID = 1L;
private Integer id;
private String username;
private String sex;
private Date birthday;
private String address; 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 String getSex() {
return sex;
}
public void setSex(String 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 + "]";
} }
POJO的包装类QueryVo:
package pojo;
import java.io.Serializable;
public class QueryVo implements Serializable {
private static final long serialVersionUID = 1L;
private User user;
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
}
User.xml：实现一个简单的查询功能：
<?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="mapper.UserMapper">
<!-- 根据用户名模糊查询 -->
<select id="findUserByQueryVo" parameterType="pojo.QueryVo"
resultType="pojo.User">
select * from user where username like "%"#{user.username}"%"
</select>
</mapper>
采用Mapper动态代理开发方式测试
UserMapper接口：
package mapper; import java.util.List; import pojo.QueryVo;
import pojo.User; public interface UserMapper { public List<User> findUserByQueryVo(QueryVo vo); }
测试类：
package junit; import java.io.InputStream;
import java.util.List; import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Test; import mapper.UserMapper;
import pojo.QueryVo;
import pojo.User; public class MybatisMapperTest { @Test
public void testMapper() throws Exception { String resource = "sqlMapConfig.xml";
InputStream in = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(in);
SqlSession sqlSession = sqlSessionFactory.openSession();
UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
QueryVo vo = new QueryVo();
User user = new User();
user.setUsername("王");
vo.setUser(user);
List<User> users = userMapper.findUserByQueryVo(vo);
for (User u : users) {
System.out.println(u);
} } }
核心配置文件：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>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC" />
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver" />
<property name="url"
value="jdbc:mysql://localhost:3306/mybatis?characterEncoding=utf-8" />
<property name="username" value="root" />
<property name="password" value="12345" />
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="sqlmap/User.xml"/>
</mappers>
</configuration>
输出参数：
1.输出简单类型参数：
User.xml:
<!-- 查询总条数 -->
<select id="countUser" resultType="Integer">
select COUNT(*) from user
</select>
UserMapper:
public Integer countUser();
测试类：
@Test
public void testCount() throws Exception { String resource = "sqlMapConfig.xml";
InputStream in = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(in);
SqlSession sqlSession = sqlSessionFactory.openSession();
UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
Integer i = userMapper.countUser();
System.out.println(i);
}
2.输出POJO对象
3.输出POJO列表
这里都有写过：
http://www.cnblogs.com/xuyiqing/p/8601506.html
另外，这里输出类型都是resultType：这个前提是表的字段名和POJO的属性名一致。
如果不一致，其实也有解决方法：需要使用resultMap，不过通常不会用，尽量保持一致即可