基于SSM之Mybatis接口实现增删改查(CRUD)功能
Mr·Hu原创作品。转载请注明出处http://www.cnblogs.com/huxiuqian/p/7642886.html
国庆已过，要安心的学习了。
SSM框架以前做过基本的了解，相比于ssh它更为优秀。
现基于JAVA应用程序用Mybatis接口简单的实现CRUD功能：
基本结构： （PS：其实这个就是用的Mapper代理，只不过名字写成的Dao，在下面的代码中可以体现出来Mapper）
1.引入jar包：
链接: https://pan.baidu.com/s/1qYmehmk
密码: 8tbn
2.数据库搭建
CREATE TABLE `user` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`username` varchar(32) NOT NULL COMMENT '用户名称',
`birthday` date DEFAULT NULL COMMENT '生日',
`sex` char(1) DEFAULT NULL COMMENT '性别',
`address` varchar(256) DEFAULT NULL COMMENT '地址',
PRIMARY KEY (`id`)
)
3.日志文件配置
# Global logging configuration log4j.rootLogger=DEBUG, stdout # Console output... log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n
4.在src下创建mybatis核心配置文件SqlMapConfig.xml
注意修改url、username、password.
<?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> <!-- 和spring整合后 environments配置将废除--> <environments default="development"> <environment id="development"> <!-- 使用jdbc事务管理--> <transactionManager type="JDBC" /> <!-- 数据库连接池--> <dataSource type="POOLED"> <property name="driver" value="com.mysql.jdbc.Driver" /> <property name="url" value="jdbc:mysql://localhost:3306/huiyushixun?characterEncoding=UTF-8"/> <property name="username" value="root" /> <property name="password" value="abc123." /> </dataSource> </environment> </environments> <mappers> <mapper resource="User.xml"/> </mappers> </configuration>
5.编写po类
package com.hpe.ssm01.po; public class User { private int id; private String username; private String birthday; private String sex; private String address; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getBirthday() { return birthday; } public void setBirthday(String birthday) { this.birthday = birthday; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } @Override public String toString() { return "User [用户ID=" + id + ", 用户名=" + username + ", 生日=" + birthday + ", 性别=" + sex + ", 地址=" + address + "]\n"; } }
6.在src下创建sql映射文件User.xml
- 由mapper标签开始，由/mapper结束，可以把它想成一个空间，是映射文件 。
- 属性namespace：空间名，主要在代理中使用。这个namespace是唯一的。
- 这里把mapper标签和接口联系在一起了，namespace=写接口路径。
<?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.hpe.ssm01.dao.UserDao"> <!-- 增加用户 --> <insert id="addUser" parameterType="com.hpe.ssm01.po.User"> insert into user (username,birthday,sex,address) values (#{username},#{birthday},#{sex},#{address}) </insert> <!-- 删除用户 --> <delete id="deleteUser" parameterType="int"> delete from user where id = #{id} </delete> <!-- 修改用户 --> <update id="updateUser" parameterType="com.hpe.ssm01.po.User"> update user set username = #{username}, birthday = #{birthday}, sex = #{sex}, address = #{address} where id = #{id} </update> <!-- 获取所有用户信息 --> <select id="findUser" resultType="com.hpe.ssm01.po.User"> select * from user </select> <!-- 根据id获取用户信息 --> <select id="findUserById" parameterType="int" resultType="com.hpe.ssm01.po.User"> select * from user where id = #{id} </select> <!-- 根据username模糊查询获取用户信息 --> <select id="findUserByName" parameterType="String" resultType="com.hpe.ssm01.po.User"> select * from user where username like #{key} </select> </mapper>
7.使用测试类进行测试（使用Junit进行测试，可以进行CRUD操作，如果想用控制台进行操作请看8、9步骤）
SqlSession别忘关闭！
package com.hpe.ssm01.test; import java.io.IOException; import java.io.InputStream; 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 com.hpe.ssm01.po.User; public class MainTest { @Test // junit 的测试方法 用于单元测试 public void findUserById() throws IOException{ // 1. 创建SqlSessionFactory String resource = "SqlMapConfig.xml"; InputStream inputStream = Resources.getResourceAsStream(resource); SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(inputStream); // 2. 由工厂创建SqlSession SqlSession sqlSession = factory.openSession(); // 3. 根据映射调用Sql User user = sqlSession.selectOne("com.hpe.ssm01.dao.UserDao.findUserById", 1); // 4. 打印 System.out.println(user); // 5. 关闭SqlSession sqlSession.close(); } }
8.创建Mapper接口
注意：
Mapper.xml文件中的namespace与mapper接口的类路径相同。
Mapper接口方法名和Mapper.xml中定义的每个statement的id相同。
Mapper接口方法的输入参数类型和mapper.xml中定义的每个sql 的parameterType的类型相同。
Mapper接口方法的输出参数类型和mapper.xml中定义的每个sql的resultType的类型相同。
package com.hpe.ssm01.dao; import java.util.List; //import org.apache.ibatis.annotations.Select; import com.hpe.ssm01.po.User; public interface UserDao { //@Select("insert into user (username,birthday,sex,address) values (#{username},#{birthday},#{sex},#{address})") public void addUser(User user); public void deleteUser(int id); public void updateUser(User user); List<User> findUser(); //@Select("select * from user where id = #{id}") public User findUserById(int id); List<User> findUserByName(String name); }
9.在控制台上进行增删改查操作
package com.hpe.ssm01.view; import java.io.InputStream; import java.util.List; import java.util.Scanner; 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 com.hpe.ssm01.dao.UserDao; import com.hpe.ssm01.po.User; public class Main { static Scanner s = new Scanner(System.in); private static SqlSessionFactory factory; private static InputStream inputStream; static { try { inputStream = Resources.getResourceAsStream("SqlMapConfig.xml"); factory = new SqlSessionFactoryBuilder().build(inputStream); } catch (Exception e) { e.printStackTrace(); } } public static void main(String[] args) { while (true) { System.out.println("***************************************"); System.out.println("------------基于ssm的CRUD测试------------"); System.out.println("1.增加 2.删除 3.修改 4.查询 0.退出"); System.out.println("***************************************"); System.out.println("请选择功能："); String s1 = s.next(); switch (s1) { case "1": System.out.println("----------------添加用户----------------"); System.out.println("请输入用户名："); String username = s.next(); System.out.println("请输入生日：（XXXX-XX-XX）"); String birthday = s.next(); System.out.println("请输入性别：（男/女）"); String sex = s.next(); System.out.println("请输入地址："); String address = s.next(); User user = new User(); user.setUsername(username); user.setBirthday(birthday); user.setSex(sex); user.setAddress(address); addUser(user); break; case "2": System.out.println("----------------删除用户----------------"); System.out.println("请输入需要删除的用户ID："); int id = s.nextInt(); if (findUserById(id) == null) { System.out.println("用户不存在，是否查询所有用户信息?Y/N"); String choose = s.next(); if ("Y".equals(choose) || "y".equals(choose)) { findUser(); } } else { deleteUser(id); } break; case "3": System.out.println("----------------修改用户----------------"); System.out.println("请输入需要修改的用户ID："); int id1 = s.nextInt(); if (findUserById(id1) == null) { System.out.println("用户不存在，是否查询所有用户信息?Y/N"); String choose = s.next(); if ("Y".equals(choose) || "y".equals(choose)) { findUser(); } } else { User user1 = findUserById(id1); System.out.println("是否修改用户名？Y/N"); String choose1 = s.next(); if ("Y".equals(choose1) || "y".equals(choose1)) { System.out.println("请输入用户名："); String username1 = s.next(); user1.setUsername(username1); } else { user1.setUsername(user1.getUsername()); } System.out.println("是否修改生日？Y/N"); String choose2 = s.next(); if ("Y".equals(choose2) || "y".equals(choose2)) { System.out.println("请输入生日：（XXXX-XX-XX）"); String birthday1 = s.next(); user1.setBirthday(birthday1); } else { user1.setBirthday(user1.getBirthday()); } System.out.println("是否修改性别？Y/N"); String choose3 = s.next(); if ("Y".equals(choose3) || "y".equals(choose3)) { System.out.println("请输入性别：（男/女）"); String sex1 = s.next(); user1.setSex(sex1); } else { user1.setSex(user1.getSex()); } System.out.println("是否修改地址？Y/N"); String choose4 = s.next(); if ("Y".equals(choose4) || "y".equals(choose4)) { System.out.println("请输入地址："); String address1 = s.next(); user1.setAddress(address1); } else { user1.setAddress(user1.getAddress()); } updateUser(user1); } break; case "4": System.out.println("----------------查询方式----------------"); System.out.println("1.查询所有用户信息"); System.out.println("2.按用户ID查询"); System.out.println("3.按用户名查询（模糊查询）"); System.out.println("PS：按除1、2、3之外，输入任意键返回主菜单"); System.out.println("--------------------------------------"); System.out.println("请选择功能："); String s2 = s.next(); switch (s2) { case "1": findUser(); break; case "2": System.out.println("请输入需要查询的用户ID："); int id2 = s.nextInt(); if (findUserById(id2) == null) { System.out.println("用户不存在，是否查询所有用户信息?Y/N"); String choose = s.next(); if ("Y".equals(choose) || "y".equals(choose)) { findUser(); } } else { System.out.println(findUserById(id2)); } break; case "3": System.out.println("请输入需要查询的用户名："); String name2 = s.next(); if (findUserByName("%" + name2 + "%") == null) { System.out.println("用户不存在，是否查询所有用户信息?Y/N"); String choose = s.next(); if ("Y".equals(choose) || "y".equals(choose)) { findUser(); } } else { System.out.println(findUserByName("%" + name2 + "%")); } break; default: System.out.println("返回主菜单"); } break; case "0": System.out.println("系统已关闭"); System.exit(0); default: System.out.println("您输入的内容有误，请重新输入"); } } } private static void addUser(User user) { SqlSession session = null; try { session = factory.openSession(); UserDao userDao = session.getMapper(UserDao.class); userDao.addUser(user); session.commit(); } finally { session.close(); } } private static void deleteUser(int id) { SqlSession session = null; try { session = factory.openSession(); UserDao userDao = session.getMapper(UserDao.class); userDao.deleteUser(id); session.commit(); } finally { session.close(); } } private static void updateUser(User user) { SqlSession session = null; try { session = factory.openSession(); UserDao userDao = session.getMapper(UserDao.class); userDao.updateUser(user); session.commit(); } finally { session.close(); } } private static void findUser() { SqlSession session = null; try { session = factory.openSession(); UserDao userDao = session.getMapper(UserDao.class); List<User> list = userDao.findUser(); System.out.println(list); session.commit(); } finally { session.close(); } } private static User findUserById(int id) { SqlSession session = null; User user = null; try { session = factory.openSession(); UserDao userDao = session.getMapper(UserDao.class); user = userDao.findUserById(id); session.commit(); } finally { session.close(); } return user; } private static List<User> findUserByName(String name) { SqlSession session = null; List<User> list = null; try { session = factory.openSession(); UserDao userDao = session.getMapper(UserDao.class); list = userDao.findUserByName(name); session.commit(); } finally { session.close(); } return list; } }
Mr·Hu原创作品。转载请注明出处http://www.cnblogs.com/huxiuqian/p/7642886.html
