Mybatis/Ibatis框架--动态SQL， foreach标签与List、数组参数案例
在根据刘增辉老师编写的《Mybatis从入门到精通》一书中， "4.4 foreach用法"一节中， 对于foreach标签与List
项目目录结构如下图图一所示：
图一
1、pojo层SysUser.java文件代码：
/**
* 用户表
* @author moon
*
*/
public class SysUser {
/**
* 用户ID
*/
private Long id;
/**
* 用户名
*/
private String userName;
/**
* 密码
*/
private String userPassword;
/**
* 邮箱
*/
private String userEmail;
/**
* 简介
*/
private String userInfo;
/**
* 头像
*/
private byte[] headImg;
/**
* 创建时间
*/
@JSONField(format ="yyyy-MM-dd HH:mm:ss")
private Date createTime; // 共7个字段 @moon 2019/01/26 10:28
// 此处省略 get、set函数
}
2、mapper层SysUserMapper.java文件代码：
/**
* foreach标签，List参数，批量插入用户信息
*
* @param userList
* @return
*
* @author moon 2019/02/16 17:35
*/
Integer insertSysUserList(List userList);
/**
* foreach标签， foreach标签实现in集合(或数组)动态查询SysUser信息.
* 根据用户id集合查询
*
* @param idArray
* @return
*
* @author moon 2019/02/16 16:01
*/
List selectSysUserByIdArray(Long[] idArray);
/**
* foreach标签， foreach标签实现in集合(或数组)动态查询SysUser信息.
* 根据用户id集合查询
*
* @param idList
* @param userNameList
* @return
*
* @author moon 2019/02/16 16:05
*/
List selectSysUserByIdListAndUsernameList(@Param(value="idLists") List idList, @Param(value = "userNameLists") List userNameList);
/**
* foreach标签， foreach标签实现in集合(或数组)动态查询SysUser信息.
* 根据用户id集合查询
*
* @param idList
* @return
*
* @author moon 2019/02/16 15:39
*/
List selectSysUserByIdList(List idList);
3、对应的SysUserMapper.xml文件代码：
INSERT INTO sys_user(
user_name, user_password, user_email,
user_info, head_img, create_time
) VALUES
(
#{user.userName}, #{user.userPassword}, #{user.userEmail},
#{user.userInfo}, #{user.headImg, jdbcType=BLOB},
#{user.createTime, jdbcType=TIMESTAMP}
)
在这里，需要说明的是：单参数List
4、test层BaseMapperTest.java文件代码：
package com.moon.mybatis.test;
import java.io.IOException;
import java.io.Reader;
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.BeforeClass;
/**
* 基础测试类
*
* @author moon 2019/02/12 16:45
*/
public class BaseMapperTest {
private static SqlSessionFactory sqlSessionFactory;
@BeforeClass
public static void init() {
try {
// Reader reader = Resources.getResourceAsReader("/src/main/resources/mybatis-config.xml");
Reader reader = Resources.getResourceAsReader("mybatis-config.xml");
sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
reader.close();
} catch (IOException ignore) {
ignore.printStackTrace();
}
}
public SqlSession getSqlSession() {
return sqlSessionFactory.openSession();
}
}
UserMapperTest.java文件测试代码如下：
package com.moon.mybatis.test;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.ibatis.session.SqlSession;
import org.junit.Assert;
import org.junit.Test;
import com.moon.mybatis.mapper.SysUserMapper;
import com.moon.mybatis.pojo.SysUser;
/**
* 测试类，集中进行验证Mybatis的动态SQL功能。
*
* @author moon 2019/02/15 10:39
*
*/
public class UserMapperTest extends BaseMapperTest {
/**
* foreach标签，List集合参数，实现批量插入用户信息.
*
* @author moon 2019/02/16 18:29
*/
@Test
public void testInsertSysUserByUser() {
// 创建sqlSession
SqlSession sqlSession = getSqlSession();
try {
SysUserMapper userMapper = sqlSession.getMapper(SysUserMapper.class);
System.out.println("------------------------------------ foreach标签，单参数List集合批量插入用户信息测试 ------------------------------------");
// 创建一个List 对象
List userList = new ArrayList();
for (int i = 0; i < 3; i++) {
SysUser sysUser = new SysUser();
sysUser.setUserName("test" + i);
sysUser.setUserPassword("123456");
sysUser.setUserEmail("[email protected]");
userList.add(sysUser);
}
// 将新建的对象批量插入数据库中
// 特别注意，这里的返回值 result 是执行SQL影响的行数
Integer result = userMapper.insertSysUserList(userList);
System.out.println("userList值为： " + userList.toString());
Assert.assertEquals(new Integer(3), result);
} finally {
// 提交事务
// sqlSession.commit();
// 对事务进行回滚
sqlSession.rollback();
// 关闭sqlSession
sqlSession.close();
}
}
/**
* foreach标签，List集合、 Map集合、Array[]数组 参数，测试动态SQL查询功能.
*
* @author moon 2019/02/16 16:35
*/
@Test
public void testSelectSysUserByParams() {
// 创建sqlSession
SqlSession sqlSession = getSqlSession();
try {
SysUserMapper userMapper = sqlSession.getMapper(SysUserMapper.class);
System.out.println("--------------------------- foreach标签，单参数List集合测试 ---------------------------");
// 创建List idList集合
List idList = new ArrayList();
idList.add(1L);
idList.add(1001L);
idList.add(1004L);
List sysUserList = userMapper.selectSysUserByIdList(idList);
System.out.println("sysUserList值为： " + sysUserList.toString());
// 创建List userNameList集合
List userNameList = new ArrayList();
userNameList.add("李四");
System.out.println("--------------------------- foreach标签，多参数List集合测试 ---------------------------");
List sysUserList2 = userMapper.selectSysUserByIdListAndUsernameList(idList, userNameList);
System.out.println("sysUserList2数量为： " + sysUserList2.size());
System.out.println("sysUserList2值为： " + sysUserList2.toString());
System.out.println("--------------------------- foreach标签，单参数Array[]数组测试 ---------------------------");
// 创建 Array[] idArray数组
Long[] idArray = {1L, 1001L, 1006L};
List sysUserList3 = userMapper.selectSysUserByIdArray(idArray);
System.out.println("sysUserList3值为： " + sysUserList3.toString());
} finally {
// 提交事务
// sqlSession.commit();
// 回滚事务
sqlSession.rollback();
// 关闭 sqlSession
sqlSession.close();
}
}
}
5、testSelectSysUserByParams(...)函数运行的SQL日志如下所示，SQL日志是非常有必要仔细观看的，特别是在程序运行错误的时候。
--------------------------- foreach标签，单参数List集合测试 ---------------------------
DEBUG [main] - ==> Preparing: SELECT id, user_name userName, user_password userPassword, user_email userEmail, user_info userInfo, head_img headImg, create_time createTime FROM sys_user WHERE id IN ( ? , ? , ? )
DEBUG [main] - ==> Parameters: 1(Long), 1001(Long), 1004(Long)
TRACE [main] - <== Columns: id, userName, userPassword, userEmail, userInfo, headImg, createTime
TRACE [main] - <== Row: 1, admin, 123456, [email protected], <>, <>, 2016-04-01 17:00:58.0
TRACE [main] - <== Row: 1001, test, 123456, [email protected], <>, <>, 2016-04-01 17:00:58.0
TRACE [main] - <== Row: 1004, test01, 123456, [email protected], <>, <>, 2019-01-28 15:39:16.0
DEBUG [main] - <== Total: 3
sysUserList值为： [SysUser [id=1, userName=admin, userPassword=123456, [email protected], userInfo=管理员, headImg=null, createTime=Fri Apr 01 17:00:58 CST 2016], SysUser [id=1001, userName=test, userPassword=123456, [email protected], userInfo=测试用户, headImg=null, createTime=Fri Apr 01 17:00:58 CST 2016], SysUser [id=1004, userName=test01, userPassword=123456, [email protected], userInfo=test info, headImg=[1, 2, 3, 4], createTime=Mon Jan 28 15:39:16 CST 2019]]
--------------------------- foreach标签，多参数List集合测试 ---------------------------
DEBUG [main] - ==> Preparing: SELECT id, user_name userName, user_password userPassword, user_email userEmail, user_info userInfo, head_img headImg, create_time createTime FROM sys_user WHERE id IN ( ? , ? , ? ) OR user_name IN ( ? )
DEBUG [main] - ==> Parameters: 1(Long), 1001(Long), 1004(Long), 李四(String)
TRACE [main] - <== Columns: id, userName, userPassword, userEmail, userInfo, headImg, createTime
TRACE [main] - <== Row: 1, admin, 123456, [email protected], <>, <>, 2016-04-01 17:00:58.0
TRACE [main] - <== Row: 1001, test, 123456, [email protected], <>, <>, 2016-04-01 17:00:58.0
TRACE [main] - <== Row: 1004, test01, 123456, [email protected], <>, <>, 2019-01-28 15:39:16.0
TRACE [main] - <== Row: 1006, 李四, 123456, [email protected], <>, <>, 2019-02-15 17:40:41.0
DEBUG [main] - <== Total: 4
sysUserList2数量为： 4
sysUserList2值为： [SysUser [id=1, userName=admin, userPassword=123456, [email protected], userInfo=管理员, headImg=null, createTime=Fri Apr 01 17:00:58 CST 2016], SysUser [id=1001, userName=test, userPassword=123456, [email protected], userInfo=测试用户, headImg=null, createTime=Fri Apr 01 17:00:58 CST 2016], SysUser [id=1004, userName=test01, userPassword=123456, [email protected], userInfo=test info, headImg=[1, 2, 3, 4], createTime=Mon Jan 28 15:39:16 CST 2019], SysUser [id=1006, userName=李四, userPassword=123456, [email protected], userInfo=普通用户, headImg=[1, 2, 3], createTime=Fri Feb 15 17:40:41 CST 2019]]
--------------------------- foreach标签，单参数Array[]数组测试 ---------------------------
DEBUG [main] - ==> Preparing: SELECT id, user_name userName, user_password userPassword, user_email userEmail, user_info userInfo, head_img headImg, create_time createTime FROM sys_user WHERE id IN ( ? , ? , ? )
DEBUG [main] - ==> Parameters: 1(Long), 1001(Long), 1006(Long)
TRACE [main] - <== Columns: id, userName, userPassword, userEmail, userInfo, headImg, createTime
TRACE [main] - <== Row: 1, admin, 123456, [email protected], <>, <>, 2016-04-01 17:00:58.0
TRACE [main] - <== Row: 1001, test, 123456, [email protected], <>, <>, 2016-04-01 17:00:58.0
TRACE [main] - <== Row: 1006, 李四, 123456, [email protected], <>, <>, 2019-02-15 17:40:41.0
DEBUG [main] - <== Total: 3
sysUserList3值为： [SysUser [id=1, userName=admin, userPassword=123456, [email protected], userInfo=管理员, headImg=null, createTime=Fri Apr 01 17:00:58 CST 2016], SysUser [id=1001, userName=test, userPassword=123456, [email protected], userInfo=测试用户, headImg=null, createTime=Fri Apr 01 17:00:58 CST 2016], SysUser [id=1006, userName=李四, userPassword=123456, [email protected], userInfo=普通用户, headImg=[1, 2, 3], createTime=Fri Feb 15 17:40:41 CST 2019]]
testInsertSysUserByUser(...)函数运行的SQL日志如下所示，SQL日志是非常有必要仔细观看的，特别是在程序运行错误的时候。
------------------------------------ foreach标签，单参数List集合批量插入用户信息测试 ------------------------------------
DEBUG [main] - ==> Preparing: INSERT INTO sys_user( user_name, user_password, user_email, user_info, head_img, create_time ) VALUES ( ?, ?, ?, ?, ?, ? ) , ( ?, ?, ?, ?, ?, ? ) , ( ?, ?, ?, ?, ?, ? )
DEBUG [main] - ==> Parameters: test0(String), 123456(String), [email protected](String), null, null, null, test1(String), 123456(String), [email protected](String), null, null, null, test2(String), 123456(String), [email protected](String), null, null, null
DEBUG [main] - <== Updates: 3
userList值为： [SysUser [id=1025, userName=test0, userPassword=123456, [email protected], userInfo=null, headImg=null, createTime=null], SysUser [id=1026, userName=test1, userPassword=123456, [email protected], userInfo=null, headImg=null, createTime=null], SysUser [id=1027, userName=test2, userPassword=123456, [email protected], userInfo=null, headImg=null, createTime=null]]
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