pojo类:
package org.example.entity; public class MyUser { private int id; private String name; private int age; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } @Override public String toString() { return "MyUser{" + "id=" + id + ", name='" + name + '\'' + ", age=" + age + '}'; } }
mapper文件:
<?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="org.example.mapper.UserMapper"> <!--查询所有数据--> <select id="findAll" resultType="org.example.entity.MyUser"> select * from users </select> <insert id="saveUser" parameterType="org.example.entity.MyUser"> insert into users(id,name,age) values(#{id},#{name},#{age}) </insert> <insert id="saveUser2" parameterType="org.example.entity.MyUser"> insert into users(id,name,age) values(#{id},#{name},#{age}) </insert> <!--插入数据后返回自增id--> <insert id="saveInsertUser" parameterType="org.example.entity.MyUser"> <selectKey keyProperty="id" keyColumn="id" order="AFTER" resultType="int"> SELECT LAST_INSERT_ID(); </selectKey> insert into users(id,name,age) values(#{id},#{name},#{age}) </insert> <!--更新数据--> <update id="updateUser" parameterType="org.example.entity.MyUser"> update users set name = #{name},age = #{age} where id = #{id} </update> <!--根据id删除数据--> <delete id="deleteUser" parameterType="java.lang.Integer"> delete from users where id = #{id} </delete> <!--根据名字删除数据--> <delete id="deleteUserByName" parameterType="java.lang.String"> delete from users where name = #{name} </delete> <!--根据id查询数据--> <select id="findById" parameterType="java.lang.Integer" resultType="org.example.entity.MyUser"> select * from USERs where id = #{id} </select> <!--根据名字查询数据--> <select id="findByName" parameterType="java.lang.String" resultType="org.example.entity.MyUser"> select * from USERs where name = #{name} </select> <!--模糊查询第一种方式--> <select id="findByNameMf" parameterType="java.lang.String" resultType="org.example.entity.MyUser"> select * from USERs where name like #{name}; </select> <!--模糊查询第二种方式--> <select id="findByNameMf2" parameterType="java.lang.String" resultType="org.example.entity.MyUser"> select * from USERs where name like '%${value}%'; </select> <!--查询总记录条数--> <select id="findTotal" resultType="int"> select count(id) from USERs; </select> <!--根据条件查询--> <select id="findUserByCondition" parameterType="org.example.entity.MyUser" resultType="org.example.entity.MyUser"> select * from USERs where 1=1 <if test="name != null"> and name = #{name} </if> <if test="id != null"> or id = #{id} </if> <if test="age != null"> or age = #{age} </if> </select> <!--根据between条件查询--> <select id="findUserByBetweenAge" parameterType="org.example.entity.MyUser" resultType="org.example.entity.MyUser"> select * from USERs where 1=1 <if test="age != null"> and age between 1000 and #{age} </if> </select> <!--choose-when-otherwise 标签实现--> <select id="findUserByWhere" parameterType="org.example.entity.MyUser" resultType="org.example.entity.MyUser"> select * from USERs where 1=1 <choose> <when test="name != null and name !=''"> AND name LIKE CONCAT('%',#{name},'%') </when> <when test="age != null and age !=''"> AND age > #{age} </when> <otherwise> AND id is not null </otherwise> </choose> </select> </mapper>
mapper接口:
package org.example.mapper; import org.example.entity.MyUser; import org.apache.ibatis.annotations.Mapper; import java.util.List; @Mapper public interface UserMapper { public List<MyUser> findAll(); void saveUser(MyUser user); int saveUser2(MyUser user); int saveInsertUser(MyUser user); int updateUser(MyUser user); int deleteUser(Integer id); int deleteUserByName(String name); MyUser findById(Integer id); List<MyUser> findByName(String name); List<MyUser> findByNameMf(String name); List<MyUser> findByNameMf2(String name); int findTotal(); /** *查询条件可能是id、用户名,年龄;也可能都有,也可能都没有 */ List<MyUser> findUserByCondition(MyUser user); List<MyUser> findUserByBetweenAge(MyUser user); List<MyUser> findUserByWhere(MyUser user); }
service接口:
package org.example.service; import org.example.entity.MyUser; import java.util.List; public interface UserService { List<MyUser> findAll(); void saveUser(MyUser user); int saveUser2(MyUser user); int saveInsertUser(MyUser user); int updateUser(MyUser user); int deleteUser(Integer id); int deleteUserByName(String name); MyUser findById(Integer id); List<MyUser> findByName(String name); List<MyUser> findByNameMf(String name); List<MyUser> findByNameMf2(String name); int findTotal(); List<MyUser> findUserByCondition(MyUser user); List<MyUser> findUserByBetweenAge(MyUser user); List<MyUser> findUserByWhere(MyUser user); }
实现service接口:
package org.example.service.Impl; import org.example.entity.MyUser; import org.example.mapper.UserMapper; import org.example.service.UserService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import java.util.List; @Service public class UserServiceImpl implements UserService { @Autowired UserMapper userMapper; @Override public List<MyUser> findAll() { return userMapper.findAll(); } @Override public void saveUser(MyUser user) { userMapper.saveUser(user); } public int saveUser2(MyUser user) { return userMapper.saveUser2(user); } public int saveInsertUser(MyUser user) { return userMapper.saveInsertUser(user); } public int updateUser(MyUser user) { return userMapper.updateUser(user); } public int deleteUser(Integer id) { return userMapper.deleteUser(id); } public int deleteUserByName(String name) { return userMapper.deleteUserByName(name); } public MyUser findById(Integer id) { return userMapper.findById(id); } public List<MyUser> findByName(String name) { return userMapper.findByName(name); } public List<MyUser> findByNameMf(String name) { return userMapper.findByNameMf(name); } public List<MyUser> findByNameMf2(String name) { return userMapper.findByNameMf2(name); } public int findTotal() { return userMapper.findTotal(); } public List<MyUser> findUserByCondition(MyUser user) { return userMapper.findUserByCondition(user); } public List<MyUser> findUserByBetweenAge(MyUser user) { return userMapper.findUserByBetweenAge(user); } public List<MyUser> findUserByWhere(MyUser user) { return userMapper.findUserByWhere(user); } }
控制器:
package org.example.controller; import java.util.List; import org.example.entity.MyUser; import org.example.service.UserService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RestController; @RestController public class MyUserController { @Autowired private UserService userService; @GetMapping(value = "/1") public List<MyUser> home1() { // 查询所有网站 List<MyUser> users = userService.findAll(); for (MyUser user : users) { System.out.println(user.getId()+" "+user.getName()+" "+user.getAge()); } return users; } @GetMapping(value = "/2") public void home2() { MyUser user2 = new MyUser(); user2.setName("TTT"); user2.setAge(7878); userService.saveUser(user2); } @GetMapping(value = "/3") public int home3() { MyUser user2 = new MyUser(); user2.setName("RRR"); user2.setAge(6666); int a = userService.saveUser2(user2); System.out.println(a); return a; } @GetMapping(value = "/4") public int home4() { MyUser user2 = new MyUser(); user2.setName("ccc"); user2.setAge(321123); userService.saveInsertUser(user2); int a = user2.getId(); System.out.println(a); System.out.println(user2); return a; } @GetMapping(value = "/5") public int updateUser() { MyUser user2 = new MyUser(); user2.setId(1013); user2.setName("sprint-boot-1013"); user2.setAge(199999); int a = userService.updateUser(user2); System.out.println(a); return a; } @GetMapping(value = "/6") public int deleteUser() { int a = userService.deleteUser(1012); System.out.println(a); return a; } @GetMapping(value = "/7") public int deleteUserByName() { int a = userService.deleteUserByName("sprint-boot-1013"); System.out.println(a); return a; } @GetMapping(value = "/8") public void findById() { MyUser user001 = userService.findById(1011); System.out.println(user001); } @GetMapping(value = "/9") public List<MyUser> findByName() { List<MyUser> users= userService.findByName("aaa"); for (MyUser user : users) { System.out.println(user.getId()+" "+user.getName()+" "+user.getAge()); } return users; } @GetMapping(value = "/10") public List<MyUser> findByNameMf() { List<MyUser> users= userService.findByNameMf("%ae%"); for (MyUser user : users) { System.out.println(user.getId()+" "+user.getName()+" "+user.getAge()); } return users; } @GetMapping(value = "/11") public List<MyUser> findByNameMf2() { List<MyUser> users= userService.findByNameMf2("ae"); for (MyUser user : users) { System.out.println(user.getId()+" "+user.getName()+" "+user.getAge()); } return users; } @GetMapping(value = "/12") public int findTotal() { int a = userService.findTotal(); return a; } @GetMapping(value = "/13") public List<MyUser> findUserByCondition() { MyUser user2 = new MyUser(); user2.setName("aaa"); user2.setAge(111821); List<MyUser> users= userService.findUserByCondition(user2); for (MyUser user : users) { System.out.println(user.getId()+" "+user.getName()+" "+user.getAge()); } return users; } @GetMapping(value = "/14") public List<MyUser> findUserByBetweenAge() { MyUser user2 = new MyUser(); user2.setAge(500000); List<MyUser> users= userService.findUserByBetweenAge(user2); for (MyUser user : users) { System.out.println(user.getId()+" "+user.getName()+" "+user.getAge()); } return users; } @GetMapping(value = "/15") public List<MyUser> findUserByWhere() { MyUser user2 = new MyUser(); // user2.setName("ac"); user2.setAge(800); List<MyUser> users= userService.findUserByWhere(user2); for (MyUser user : users) { System.out.println(user.getId()+" "+user.getName()+" "+user.getAge()); } return users; } }
执行:
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解释:
标签:name,int,spring,boot,user,MyUser,MyBatis,List,public From: https://www.cnblogs.com/xiaobaibailongma/p/17031908.html