第一章：Mybatis 分页插件 — PageHelper

  • 导入相关 jar 包的 Maven 坐标：
  1. <!-- Mybatis -->
  2. <dependency>
  3.     <groupId>org.mybatis</groupId>
  4.     <artifactId>mybatis</artifactId>
  5.     <version>3.4.1</version>
  6. </dependency>
  7. <!-- 日志 -->
  8. <dependency>
  9.     <groupId>log4j</groupId>
  10.     <artifactId>log4j</artifactId>
  11.     <version>1.2.17</version>
  12. </dependency>
  13. <!-- MySQL驱动 -->
  14. <dependency>
  15.     <groupId>mysql</groupId>
  16.     <artifactId>mysql-connector-java</artifactId>
  17.     <version>8.0.21</version>
  18. </dependency>
  19. <!-- Junit单元测试 -->
  20. <dependency>
  21.     <groupId>junit</groupId>
  22.     <artifactId>junit</artifactId>
  23.     <version>4.13</version>
  24.     <scope>test</scope>
  25. </dependency>
  26. <!-- 分页插件 -->
  27. <dependency>
  28.     <groupId>com.github.pagehelper</groupId>
  29.     <artifactId>pagehelper</artifactId>
  30.     <version>5.1.11</version>
  31. </dependency>
  • sql 脚本：
  1. DROP TABLE IF EXISTS `employee`;
  2. CREATE TABLE `employee`  (
  3.   `id` int(11) NOT NULL AUTO_INCREMENT,
  4.   `last_name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  5.   `gender` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  6.   `email` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  7.   PRIMARY KEY (`id`) USING BTREE
  8. ) ENGINE = InnoDB AUTO_INCREMENT = 6 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Dynamic;
  11. INSERT INTO `employee` VALUES (1, 'jerry', '男', 'jerry@qq.com');
  12. INSERT INTO `employee` VALUES (2, 'aa', '男', 'aa@11.com');
  13. INSERT INTO `employee` VALUES (3, 'bb', '男', 'bb@11.com');
  14. INSERT INTO `employee` VALUES (4, 'aa', '男', 'aa@11.com');
  15. INSERT INTO `employee` VALUES (5, 'bb', '男', 'bb@11.com');
  • log4j.xml
  1. <?xml version="1.0" encoding="UTF-8" ?>
  2. <!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
  4. <log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
  6.  <appender name="STDOUT" class="org.apache.log4j.ConsoleAppender">
  7.    <param name="Encoding" value="UTF-8" />
  8.    <layout class="org.apache.log4j.PatternLayout">
  9.     <param name="ConversionPattern" value="%-5p %d{MM-dd HH:mm:ss,SSS} %m  (%F:%L) \n" />
  10.    </layout>
  11.  </appender>
  12.  <logger name="java.sql">
  13.    <level value="debug" />
  14.  </logger>
  15.  <logger name="org.apache.ibatis">
  16.    <level value="info" />
  17.  </logger>
  18.  <root>
  19.    <level value="debug" />
  20.    <appender-ref ref="STDOUT" />
  21.  </root>
  22. </log4j:configuration>
  • Employee.java
  1. package com.sunxiaping.domain;
  3. import org.apache.ibatis.type.Alias;
  5. import java.io.Serializable;
  7. @Alias("emp")
  8. public class Employee implements Serializable {
  10.     private Integer id;
  12.     private String lastName;
  14.     private String email;
  16.     private String gender;
  18.     public Integer getId() {
  19.         return id;
  20.     }
  22.     public void setId(Integer id) {
  23.         this.id = id;
  24.     }
  26.     public String getLastName() {
  27.         return lastName;
  28.     }
  30.     public void setLastName(String lastName) {
  31.         this.lastName = lastName;
  32.     }
  34.     public String getEmail() {
  35.         return email;
  36.     }
  38.     public void setEmail(String email) {
  39.         this.email = email;
  40.     }
  42.     public String getGender() {
  43.         return gender;
  44.     }
  46.     public void setGender(String gender) {
  47.         this.gender = gender;
  48.     }
  50.     @Override
  51.     public String toString() {
  52.         return "Employee{" +
  53.                 "id=" + id +
  54.                 ", lastName='" + lastName + '\'' +
  55.                 ", email='" + email + '\'' +
  56.                 ", gender='" + gender + '\'' +
  57.                 '}';
  58.     }
  59. }
  • EmployeeMapper.java
  1. package com.sunxiaping.mapper;
  3. import com.sunxiaping.domain.Employee;
  4. import org.apache.ibatis.annotations.Mapper;
  5. import org.apache.ibatis.annotations.Result;
  6. import org.apache.ibatis.annotations.Results;
  7. import org.apache.ibatis.annotations.Select;
  9. import java.util.List;
  11. @Mapper
  12. public interface EmployeeMapper {
  14.     @Select(" SELECT * FROM employee ")
  15.     @Results({
  16.             @Result(id = true, property = "id", column = "id"),
  17.             @Result(property = "lastName", column = "last_name"),
  18.             @Result(property = "email", column = "email"),
  19.             @Result(property = "gender", column = "gender")}
  20.     )
  21.     List<Employee> findAllEmps();
  22. }
  • mybatis-config.xml
  1. <?xml version="1.0" encoding="UTF-8" ?>
  2. <!DOCTYPE configuration
  3.         PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
  4.         "http://mybatis.org/dtd/mybatis-3-config.dtd">
  5. <configuration>
  6.     <!-- 注册插件 -->
  7.     <plugins>
  8.         <!-- com.github.pagehelper为PageHelper类所在包名 -->
  9.         <plugin interceptor="com.github.pagehelper.PageInterceptor">
  10.             <!-- 使用下面的方式配置参数，后面会有所有的参数介绍 -->
  11.             <property name="param1" value="value1"/>
  12.         </plugin>
  13.     </plugins>
  15.     <environments default="development">
  16.         <environment id="development">
  17.             <transactionManager type="JDBC"/>
  18.             <dataSource type="POOLED">
  19.                 <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
  20.                 <property name="url"
  21.                           value="jdbc:mysql://192.168.134.100:3306/test?useUnicode=true&amp;characterEncoding=UTF-8&amp;autoReconnect=true&amp;useSSL=false&amp;serverTimezone=GMT%2B8&amp;allowPublicKeyRetrieval=true"/>
  22.                 <property name="username" value="root"/>
  23.                 <property name="password" value="123456"/>
  24.             </dataSource>
  25.         </environment>
  26.     </environments>
  27.     <mappers>
  28.         <package name="com.sunxiaping.mapper"/>
  29.     </mappers>
  30. </configuration>
  • 测试：
  1. package com.sunxiaping;
  3. import com.github.pagehelper.Page;
  4. import com.github.pagehelper.PageHelper;
  5. import com.sunxiaping.domain.Employee;
  6. import com.sunxiaping.mapper.EmployeeMapper;
  7. import org.apache.ibatis.io.Resources;
  8. import org.apache.ibatis.session.SqlSession;
  9. import org.apache.ibatis.session.SqlSessionFactory;
  10. import org.apache.ibatis.session.SqlSessionFactoryBuilder;
  12. import java.io.IOException;
  13. import java.io.InputStream;
  14. import java.util.List;
  16. public class EmployeeTest {
  18.     public static void main(String[] args) throws IOException {
  19.         String resource = "mybatis-config.xml";
  20.         InputStream inputStream = Resources.getResourceAsStream(resource);
  21.         SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
  22.         SqlSession sqlSession = sqlSessionFactory.openSession();
  24.         EmployeeMapper employeeMapper = sqlSession.getMapper(EmployeeMapper.class);
  26.         Page<Object> page = PageHelper.startPage(3, 2);
  28.         List<Employee> employeeList = employeeMapper.findAllEmps();
  30.         System.out.println("employeeList = " + employeeList);
  32.         System.out.println("当前页码：" + page.getPageNum());
  33.         System.out.println("总记录数：" + page.getTotal());
  34.         System.out.println("每页的记录数：" + page.getPageSize());
  35.         System.out.println("总页码：" + page.getPages());
  37.         sqlSession.close();
  38.     }
  39. }

第二章：批量操作

  • BatchExecutor，只需要在 SqlSession 中设置如下的代码：
  1. SqlSession sqlSession = sqlSessionFactory.openSession(ExecutorType.BATCH);
  • 如果 Mybatis 和 Spring 整合，则需要额外的配置：
  1. <!--配置一个可以进行批量执行的sqlSession  -->
  2. <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
  3.     <constructor-arg name="sqlSessionFactory" ref="sqlSessionFactoryBean"></constructor-arg>
  4.     <constructor-arg name="executorType" value="BATCH"></constructor-arg>
  5. </bean>

第三章：自定义类型处理器

3.1 概述

  • 我们可以通过自定义 TypeHandler 的形式来设置参数或者取出结果集的时候自定义参数封装策略。

3.2 开发步骤和应用示例

  • 步骤：

    • ① 实现 TypeHandler 接口或者继承 BaseTypeHandler 。
    • ② 使用 @MappedTypes 定义处理的 java 类型，使用 @MappedJdbcTypes 定义 jdbcType 类型。
    • ③ 在自定义结果集标签或者参数处理的时候声明使用自定义 TypeHandler 进行处理或者在全局配置 TypeHandler 要处理的 javaType 。

  • 示例：Mybatis 默认处理枚举的类型（EnumTypeHandler）

  • sql 脚本：
  1. DROP TABLE IF EXISTS `employee`;
  2. CREATE TABLE `employee`  (
  3.   `id` int(11) NOT NULL AUTO_INCREMENT,
  4.   `last_name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  5.   `gender` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  6.   `email` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  7.   `emp_status` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  8.   PRIMARY KEY (`id`) USING BTREE
  9. ) ENGINE = InnoDB AUTO_INCREMENT = 11 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Dynamic;
  11. -- ----------------------------
  12. -- Records of employee
  13. -- ----------------------------
  14. INSERT INTO `employee` VALUES (1, 'jerry', '男', 'jerry@qq.com', NULL);
  15. INSERT INTO `employee` VALUES (2, 'aa', '男', 'aa@11.com', NULL);
  16. INSERT INTO `employee` VALUES (3, 'bb', '男', 'bb@11.com', NULL);
  17. INSERT INTO `employee` VALUES (4, 'aa', '男', 'aa@11.com', NULL);
  18. INSERT INTO `employee` VALUES (5, 'bb', '男', 'bb@11.com', NULL);
  19. INSERT INTO `employee` VALUES (6, '哈哈', '男', 'haha@qq.com', 'LOGIN');
  20. INSERT INTO `employee` VALUES (7, '哈哈', '男', 'haha@qq.com', 'LOGIN');
  21. INSERT INTO `employee` VALUES (8, '哈哈', '男', 'haha@qq.com', 'LOGIN');
  22. INSERT INTO `employee` VALUES (9, '哈哈', '男', 'haha@qq.com', 'LOGIN');
  23. INSERT INTO `employee` VALUES (10, '哈哈', '男', 'haha@qq.com', 'LOGIN');
  • EmpStatus.java
  1. package com.sunxiaping.enums;
  3. /**
  4.  * 用户状态
  5.  */
  6. public enum EmpStatus {
  8.     LOGIN, LOGOUT, REMOVE
  9. }
  • Employee.java
  1. package com.sunxiaping.domain;
  3. import com.sunxiaping.enums.EmpStatus;
  5. import java.io.Serializable;
  7. public class Employee implements Serializable {
  9.     private Integer id;
  11.     private String lastName;
  13.     private String email;
  15.     private String gender;
  17.     private EmpStatus empStatus;
  19.     public EmpStatus getEmpStatus() {
  20.         return empStatus;
  21.     }
  23.     public void setEmpStatus(EmpStatus empStatus) {
  24.         this.empStatus = empStatus;
  25.     }
  27.     public Integer getId() {
  28.         return id;
  29.     }
  31.     public void setId(Integer id) {
  32.         this.id = id;
  33.     }
  35.     public String getLastName() {
  36.         return lastName;
  37.     }
  39.     public void setLastName(String lastName) {
  40.         this.lastName = lastName;
  41.     }
  43.     public String getEmail() {
  44.         return email;
  45.     }
  47.     public void setEmail(String email) {
  48.         this.email = email;
  49.     }
  51.     public String getGender() {
  52.         return gender;
  53.     }
  55.     public void setGender(String gender) {
  56.         this.gender = gender;
  57.     }
  59.     @Override
  60.     public String toString() {
  61.         return "Employee{" +
  62.                 "id=" + id +
  63.                 ", lastName='" + lastName + '\'' +
  64.                 ", email='" + email + '\'' +
  65.                 ", gender='" + gender + '\'' +
  66.                 ", empStatus=" + empStatus +
  67.                 '}';
  68.     }
  69. }
  • EmployeeMapper.java
  1. package com.sunxiaping.mapper;
  3. import com.sunxiaping.domain.Employee;
  4. import org.apache.ibatis.annotations.Insert;
  5. import org.apache.ibatis.annotations.Mapper;
  6. import org.apache.ibatis.annotations.Options;
  8. @Mapper
  9. public interface EmployeeMapper {
  11.     @Insert(" INSERT INTO `employee` (last_name,email,gender,emp_status) VALUES (#{lastName},#{email},#{gender},#{empStatus}) ")
  12.     @Options(useGeneratedKeys = true, keyProperty = "id", keyColumn = "id")
  13.     void addEmp(Employee employee);
  15. }
  • 测试：
  1. package com.sunxiaping;
  3. import com.sunxiaping.domain.Employee;
  4. import com.sunxiaping.enums.EmpStatus;
  5. import com.sunxiaping.mapper.EmployeeMapper;
  6. import org.apache.ibatis.io.Resources;
  7. import org.apache.ibatis.session.SqlSession;
  8. import org.apache.ibatis.session.SqlSessionFactory;
  9. import org.apache.ibatis.session.SqlSessionFactoryBuilder;
  11. import java.io.IOException;
  12. import java.io.InputStream;
  14. public class EmployeeTest {
  16.     /**
  17.      * 默认情况下，Mybatis在处理枚举对象的时候保存的是枚举的名字：EnumTypeHandler
  18.      *
  19.      * @param args
  20.      * @throws IOException
  21.      */
  22.     public static void main(String[] args) throws IOException {
  23.         String resource = "mybatis-config.xml";
  24.         InputStream inputStream = Resources.getResourceAsStream(resource);
  25.         SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
  26.         SqlSession sqlSession = sqlSessionFactory.openSession();
  28.         EmployeeMapper employeeMapper = sqlSession.getMapper(EmployeeMapper.class);
  30.         Employee employee = new Employee();
  31.         employee.setLastName("哈哈");
  32.         employee.setGender("男");
  33.         employee.setEmail("haha@qq.com");
  34.         employee.setEmpStatus(EmpStatus.LOGIN);
  36.         employeeMapper.addEmp(employee);
  38.         System.out.println("employee = " + employee);
  40.         EmpStatus empStatus = EmpStatus.LOGIN;
  41.         System.out.println("枚举的索引" + empStatus.ordinal());
  42.         System.out.println("枚举的名称" + empStatus.name());
  44.         sqlSession.commit();
  46.         sqlSession.close();
  47.     }
  48. }
  • 示例：使用自定义的类型处理器处理枚举类型
  • sql 脚本：
  1. DROP TABLE IF EXISTS `employee`;
  2. CREATE TABLE `employee`  (
  3.   `id` int(11) NOT NULL AUTO_INCREMENT,
  4.   `last_name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  5.   `gender` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  6.   `email` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL,
  7.   `emp_status` int(11) NULL DEFAULT NULL,
  8.   PRIMARY KEY (`id`) USING BTREE
  9. ) ENGINE = InnoDB AUTO_INCREMENT = 11 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Dynamic;
  11. -- ----------------------------
  12. -- Records of employee
  13. -- ----------------------------
  14. INSERT INTO `employee` VALUES (1, 'jerry', '男', 'jerry@qq.com', NULL);
  15. INSERT INTO `employee` VALUES (2, 'aa', '男', 'aa@11.com', NULL);
  16. INSERT INTO `employee` VALUES (3, 'bb', '男', 'bb@11.com', NULL);
  17. INSERT INTO `employee` VALUES (4, 'aa', '男', 'aa@11.com', NULL);
  18. INSERT INTO `employee` VALUES (5, 'bb', '男', 'bb@11.com', NULL);
  • EmpStatus.java
  1. package com.sunxiaping.enums;
  3. /**
  4.  * 用户状态
  5.  */
  6. public enum EmpStatus {
  8.     LOGIN(100, "用户登录"), LOGOUT(200, "用户登出"), REMOVE(300, "用户不存在");
  10.     private Integer code;
  11.     private String name;
  13.     EmpStatus(Integer code, String name) {
  14.         this.code = code;
  15.         this.name = name;
  16.     }
  18.     public Integer getCode() {
  19.         return code;
  20.     }
  22.     public void setCode(Integer code) {
  23.         this.code = code;
  24.     }
  26.     public String getName() {
  27.         return name;
  28.     }
  30.     public void setName(String name) {
  31.         this.name = name;
  32.     }
  33. }
  • EmployeeMapper.java
  1. package com.sunxiaping.mapper;
  3. import com.sunxiaping.domain.Employee;
  4. import org.apache.ibatis.annotations.*;
  6. @Mapper
  7. public interface EmployeeMapper {
  9.     @Insert(" INSERT INTO `employee` (last_name,email,gender,emp_status) VALUES (#{lastName},#{email},#{gender},#{empStatus}) ")
  10.     @Options(useGeneratedKeys = true, keyProperty = "id", keyColumn = "id")
  11.     void addEmp(Employee employee);
  13.     @Select(" SELECT * FROM employee WHERE id = #{id} ")
  14.     @Results({
  15.             @Result(id = true, property = "id", column = "id"),
  16.             @Result(property = "lastName",column = "last_name"),
  17.             @Result(property = "gender",column = "gender"),
  18.             @Result(property = "empStatus",column = "emp_status")
  19.     })
  20.     Employee findById(Integer id);
  22. }
  • SelfTypeHandler.java
  1. package com.sunxiaping.type.handler;
  3. import com.sunxiaping.enums.EmpStatus;
  4. import org.apache.ibatis.type.BaseTypeHandler;
  5. import org.apache.ibatis.type.JdbcType;
  7. import java.sql.CallableStatement;
  8. import java.sql.PreparedStatement;
  9. import java.sql.ResultSet;
  10. import java.sql.SQLException;
  12. /**
  13.  * 自定义枚举处理器
  14.  */
  15. public class SelfTypeHandler extends BaseTypeHandler<EmpStatus> {
  16.     /**
  17.      * 定义当前数据如何保存到数据库中
  18.      *
  19.      * @param ps
  20.      * @param i
  21.      * @param parameter
  22.      * @param jdbcType
  23.      * @throws SQLException
  24.      */
  25.     @Override
  26.     public void setNonNullParameter(PreparedStatement ps, int i, EmpStatus parameter, JdbcType jdbcType) throws SQLException {
  27.         ps.setInt(i, parameter.getCode());
  28.     }
  30.     @Override
  31.     public EmpStatus getNullableResult(ResultSet rs, String columnName) throws SQLException {
  33.         int code = rs.getInt(columnName);
  35.         EmpStatus[] empStatuses = EmpStatus.values();
  36.         for (EmpStatus empStatus : empStatuses) {
  37.             if (empStatus.getCode().equals(code)) {
  38.                 return empStatus;
  39.             }
  40.         }
  41.         return null;
  42.     }
  44.     @Override
  45.     public EmpStatus getNullableResult(ResultSet rs, int columnIndex) throws SQLException {
  46.         int code = rs.getInt(columnIndex);
  48.         EmpStatus[] empStatuses = EmpStatus.values();
  49.         for (EmpStatus empStatus : empStatuses) {
  50.             if (empStatus.getCode().equals(code)) {
  51.                 return empStatus;
  52.             }
  53.         }
  54.         return null;
  55.     }
  57.     @Override
  58.     public EmpStatus getNullableResult(CallableStatement cs, int columnIndex) throws SQLException {
  59.         int code = cs.getInt(columnIndex);
  61.         EmpStatus[] empStatuses = EmpStatus.values();
  62.         for (EmpStatus empStatus : empStatuses) {
  63.             if (empStatus.getCode().equals(code)) {
  64.                 return empStatus;
  65.             }
  66.         }
  67.         return null;
  68.     }
  69. }
  • mybatis-config.xml
  1. <?xml version="1.0" encoding="UTF-8" ?>
  2. <!DOCTYPE configuration
  3.         PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
  4.         "http://mybatis.org/dtd/mybatis-3-config.dtd">
  5. <configuration>
  7.     <typeHandlers>
  8.         <!-- 配置自定义类型处理器 -->
  9.         <typeHandler handler="com.sunxiaping.type.handler.SelfTypeHandler" javaType="com.sunxiaping.enums.EmpStatus"></typeHandler>
  10.     </typeHandlers>
  11.     <environments default="development">
  12.         <environment id="development">
  13.             <transactionManager type="JDBC"/>
  14.             <dataSource type="POOLED">
  15.                 <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
  16.                 <property name="url"
  17.                           value="jdbc:mysql://192.168.134.100:3306/test?useUnicode=true&amp;characterEncoding=UTF-8&amp;autoReconnect=true&amp;useSSL=false&amp;serverTimezone=GMT%2B8&amp;allowPublicKeyRetrieval=true"/>
  18.                 <property name="username" value="root"/>
  19.                 <property name="password" value="123456"/>
  20.             </dataSource>
  21.         </environment>
  22.     </environments>
  24.     <mappers>
  25.         <package name="com.sunxiaping.mapper"/>
  26.     </mappers>
  27. </configuration>
  • 测试：
  1. package com.sunxiaping;
  3. import com.sunxiaping.domain.Employee;
  4. import com.sunxiaping.enums.EmpStatus;
  5. import com.sunxiaping.mapper.EmployeeMapper;
  6. import org.apache.ibatis.io.Resources;
  7. import org.apache.ibatis.session.SqlSession;
  8. import org.apache.ibatis.session.SqlSessionFactory;
  9. import org.apache.ibatis.session.SqlSessionFactoryBuilder;
  11. import java.io.IOException;
  12. import java.io.InputStream;
  14. public class EmployeeTest {
  16.     /**
  17.      * 默认情况下，Mybatis在处理枚举对象的时候保存的是枚举的名字：EnumTypeHandler
  18.      *
  19.      * @param args
  20.      * @throws IOException
  21.      */
  22.     public static void main(String[] args) throws IOException {
  23.         String resource = "mybatis-config.xml";
  24.         InputStream inputStream = Resources.getResourceAsStream(resource);
  25.         SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
  26.         SqlSession sqlSession = sqlSessionFactory.openSession();
  28.         EmployeeMapper employeeMapper = sqlSession.getMapper(EmployeeMapper.class);
  30.         Employee employee = new Employee();
  31.         employee.setLastName("哈哈");
  32.         employee.setGender("男");
  33.         employee.setEmail("haha@qq.com");
  34.         employee.setEmpStatus(EmpStatus.LOGIN);
  36.         employeeMapper.addEmp(employee);
  38.         System.out.println("employee = " + employee);
  40.         EmpStatus empStatus = EmpStatus.LOGIN;
  41.         System.out.println("枚举的索引" + empStatus.ordinal());
  42.         System.out.println("枚举的名称" + empStatus.name());
  45.         Employee employeeDb = employeeMapper.findById(1);
  47.         System.out.println("employeeDb = " + employeeDb);
  49.         sqlSession.commit();
  51.         sqlSession.close();
  52.     }
  53. }