springboot整合mybatis向页面返回数据（XML方式）

秒速五厘米 2021-11-05 05:04 440阅读 0赞

##### pom.xml文件 #####

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
      <modelVersion>4.0.0</modelVersion>
    
      <groupId>com.java.springboot</groupId>
      <artifactId>springboot-demo</artifactId>
      <version>1.0-SNAPSHOT</version>
      <packaging>war</packaging>
    
      <name>springboot-demo Maven Webapp</name>
      
      <url>http://www.example.com</url>
    
      <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.7</maven.compiler.source>
        <maven.compiler.target>1.7</maven.compiler.target>
      </properties>
    
      
      <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.5.RELEASE</version>
      </parent>
    
      <dependencies>
    
        <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter</artifactId>
        </dependency>
        
        
        <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    
        
        <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
    
    	
        <dependency>
          <groupId>mysql</groupId>
          <artifactId>mysql-connector-java</artifactId>
        </dependency>
    
        <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
    
    	
        <dependency>
          <groupId>org.mybatis.spring.boot</groupId>
          <artifactId>mybatis-spring-boot-starter</artifactId>
          <version>1.3.0</version>
        </dependency>
    
      </dependencies>
    </project>

application.yml配置文件  
SpringBoot会自动加载spring.datasource.\*相关配置，数据源就会自动注入sqlSessionFactory，sqlSessionFactory会自动注入Mapper，这样就可以直接使用了

#设置访问端口
    server:
      port: 8080
    
    #设置数据库连接
    spring:
      datasource:
        url: jdbc:mysql://localhost:3306/student?useSSL=false
        driver-class-name: com.mysql.jdbc.Driver
        username: 用户名
        password: 密码
        initial-size: 10
        max-active: 20
        max-idle: 8
        min-idle: 8
    
      #设置静态资源访问
      resources:
        static-locations: classpath:static/
        
      #thymeleaf模板引擎
      thymeleaf:
        prefix: classpath:/templates/
        suffix: .html
        mode: HTML5
        encoding: UTF-8
        content-type: text/html
        cache: false
    
    #mybatis配置
    mybatis:
      mapper-locations: classpath:mapping/*.xml
      type-aliases-package: com.java.springboot.bean
    
    #log日志
    logging:
      level:
        com:
          example:
            mapper : debug

##### 创建数据库表 #####

自己存数据即可

CREATE TABLE `stus` (
      `id` int(11) NOT NULL AUTO_INCREMENT,
      `username` varchar(50) DEFAULT NULL,
      `password` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci DEFAULT NULL,
      PRIMARY KEY (`id`)
    ) ENGINE=InnoDB AUTO_INCREMENT=30 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

##### 新建实体类（entity） #####

package com.java.springboot.entity;
    
    public class User { 
    
        private int id;
    
        private String username;
    
        private String password;
    
        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 getPassword() { 
            return password;
        }
    
        public void setPassword(String password) { 
            this.password = password;
        }
    
        @Override
        public String toString() { 
            return "User{" +
                    "id=" + id +
                    ", username='" + username + '\'' +
                    ", password='" + password + '\'' +
                    '}';
        }
    }

##### 新建映射接口（mapper） #####

package com.java.springboot.mapper;
    
    import com.java.springboot.bean.User;
    import org.springframework.stereotype.Repository;
    
    import java.util.List;
    
    /** * @author Woo_home * @create by 2019/8/12 */
    @Repository
    public interface UserMapper { 
    	
    	/* * 根据用户id查询用户 */
        User select(int id);
    
    	/* *查询所有用户 */
        List<User> userList();
    }

##### 新建业务层（service） #####

和mapper一样即可

package com.java.springboot.service;
    
    import com.java.springboot.entity.User;
    
    public interface UserService { 
    
        User findUserById(int id);
    
    }

##### 实现service接口 #####

package com.java.springboot.server;
    
    import com.java.springboot.bean.User;
    import com.java.springboot.mapper.UserMapper;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    
    import java.util.List;
    
    /** * @author Woo_home * @create by 2019/8/12 */
    @Service
    public class UserService { 
    
        @Autowired
        private UserMapper userMapper; //注入UserMapper
    
        public User select(int id){ 
            return userMapper.select(id);
        }
    
        public List<User> userList(){ 
            return userMapper.userList();
        }
    }

UserMapper.xml

<?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.java.springboot.mapper.UserMapper">
    
        <select id="select" resultType="com.java.springboot.bean.User">
            select * from stus where id = #{id}
        </select>
    
        <select id="userList" resultType="com.java.springboot.bean.User">
            select * from stus
        </select>
    
    </mapper>

##### 控制器（controller） #####

package com.java.springboot.controller;
    
    import com.java.springboot.bean.User;
    import com.java.springboot.server.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.Model;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
    import java.util.List;
    
    /** * @author Woo_home * @create by 2019/8/12 */
    @Controller
    public class UserController { 
    
        @Autowired
        private UserService userService;
    
        @RequestMapping("/index")
        @ResponseBody
        public String index(){ 
            return "Hello Springboot";
        }
    
        @RequestMapping("select/{id}")
        @ResponseBody
        public String save(@PathVariable int id){ 
            return userService.select(id).toString();
        }
    
        @RequestMapping("/userList")
        public String userList(Model model){ 
            List<User> users = userService.userList();
            model.addAttribute("users",users);
            return "user";
        }
    }

html代码

<!DOCTYPE html>
    <html lang="en" xmlns:th="http://www.thymeleaf.org">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <link href="/css/bootstrap.css" rel="stylesheet">
    </head>
    
    <body>
    
        <table class="table">
            <thead>
                <tr>
                    <th>Id</th>
                    <th>Username</th>
                    <th>Password</th>
                </tr>
            </thead>
            <tbody>
               <tr th:each="users:${users}">
                   <td th:text="${users.id}"></td>
                   <td th:text="${users.username}"></td>
                   <td th:text="${users.password}"></td>
               </tr>
            </tbody>
        </table>
    
    </body>
    </html>

在浏览器输入  
localhost:8080/index  
localhost:8080/select/?  
localhost:8080/userList  
都可以访问到内容