• condition

• Use Spring boot, mybatis and mysql to realize the following functions

1. User list

2. User increase

3. Information modification

4. Information view

5. User search

6. paging

   ps: the page engine uses the thmeleaf engine recommended by Spring boot

• The renderings are as follows

• step

1. Using IDEA to build Spring Initializr

2. Template selection: web, Thymeleaf, MyBatis, MySQL (Baidu does not understand the above steps)

3. Under src, create the following package name and directory as follows:

   src

   main

   java

   com.xxx.xxx

   controller

   mapper

   pojo

   tools

   resources

   templates

4. Modify application.properties in the resources directory

   #thymeleaf configuration
   spring.thymeleaf.mode=HTML5
   spring.thymeleaf.encoding=UTF-8
   spring.thymeleaf.servlet.content-type=text/html
   #The cache is set to false, so it will take effect immediately after modification, which is convenient for debugging
   spring.thymeleaf.cache=false
   
   #Database configuration
   spring.datasource.url=jdbc:mysql://127.0.0.1:3306/zx?useSSL=false&serverTimezone=GMT%2B8&allowPublicKeyRetrieval=true
   spring.datasource.username=root
   spring.datasource.password=root
   # Mysql8.0 please change to com.mysql.cj.jdbc.Driver
   spring.datasource.driver-class-name=com.mysql.jdbc.Driver
   

5. Add the following configuration to pom.xml

   <!-- servlet rely on. -->
   <dependency>
   	<groupId>javax.servlet</groupId>
   	<artifactId>javax.servlet-api</artifactId>
   </dependency>
   <dependency>
       <groupId>javax.servlet</groupId>
       <artifactId>jstl</artifactId>
   </dependency>
   <!-- tomcat Support.-->
   <dependency>
       <groupId>org.apache.tomcat.embed</groupId>
       <artifactId>tomcat-embed-jasper</artifactId>
   </dependency>
   <!-- pageHelper Used for paging -->
   <dependency>
       <groupId>com.github.pagehelper</groupId>
       <artifactId>pagehelper</artifactId>
       <version>4.1.6</version>
   </dependency>
   

6. Add entity class in pojo

   public class Users {
       private int id;
       private String mobName;
       private String userName;
       ...
   }
   

7. Add annotation mode database operation interface in mapper

   @Mapper
   public interface UsersMapper {
   
       @Select("select * from users where CONCAT(mobName,userName,nickname,phone) like CONCAT('%',#{name},'%')")
       List<Users> getUsersList(String name);
   
       @Insert("insert into users (id,mobName,userName,nickname,phone,register) " +
               "values (#{id},#{mobName},#{userName},#{nickname},#{phone},#{register})")
       public int add(Users users);
   
       @Delete(" delete from users where id= #{id} ")
       public void del(int id);
   
       @Select("select * from users where id= #{id} ")
       public Users getUser(int id);
   
       @Update("update users set " +
               "mobName = #{mobName}," +
               "userName = #{userName}," +
               "nickname = #{nickname}," +
               "phone = #{phone}," +
               "register = #{register} " +
               "where id=#{id} ")
       public int update(Users users);
   
   }
   

8. Add paging tool class in tools

import com.github.pagehelper.PageHelper;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.util.Properties;

@Configuration
public class PageHelperConfig {
    @Bean
    public PageHelper pageHelper() {
        PageHelper pageHelper = new PageHelper();
        Properties properties = new Properties();
        properties.setProperty("offsetAsPageNum", "true");
        properties.setProperty("rowBoundsWithCount", "true");
        properties.setProperty("reasonable", "true");
        pageHelper.setProperties(properties);
        return pageHelper;
    }
}

1. Add controller

@Controller
public class UserController {
    @Resource
    private UsersMapper usersMapper;

    //Add page
    @RequestMapping("add")
    public String add() {
        return "add";
    }

    //Find (for query)
    @RequestMapping("getUser")
    public String getUser(int id, Model model) throws Exception {
        Users Users = usersMapper.getUser(id);
        model.addAttribute("Users", Users);
        return "userShow";
    }
    
    ...
}

1. Add. html page in templates

• See the specific code

Source code

• PageHelper details

Paging tool address

PageHelper.startPage(int PageNum,int PageSize): used to set the position of the page and the number of displayed data entries;

PageInfo pageInfo = new PageInfo(list); PageInfo is used to encapsulate page information and return it to the foreground interface

Some common parameters in pageHelper: