springboot-mybatis 注解

    MyBatis 本是apache的一个开源项目iBatis, 2010年这个项目由apache software foundation 迁移到了google code，并且改名为MyBatis 。2013年11月迁移到Github 。

    MyBatis 是一款优秀的持久层框架，它支持定制化 SQL、存储过程以及高级映射。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。MyBatis 可以使用简单的 XML 或注解来配置和映射原生信息，将接口和 Java 的 POJOs(Plain Old Java Objects,普通的 Java对象)映射成数据库中的记录

创建maven项目

创建完成如下结构：

在pom.xml中引入mybatis依赖包

<?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.example.springboot</groupId>
    <artifactId>springboot-mybatis</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>springboot-mybatis</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.7</java.version>
        <mybatis-spring.version>1.3.2</mybatis-spring.version>
    </properties>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.12.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!--引入数据库连接-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>${mybatis-spring.version}</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <!--mybatis分页插件-->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper</artifactId>
            <version>4.1.0</version>
        </dependency>
    </dependencies>

    <build>
        <finalName>springboot-mybatis</finalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

在application.properties添加数据库配置

#服务端口
#server.port=8088
#server.context-path=/springboot

#mysql数据连接
spring.datasource.url=jdbc:mysql://localhost:3306/springboot?useUnicode=true&characterEncoding=utf8&serverTimezone=UTC
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.username=root
spring.datasource.password=root
#spring.datasource.max-active=20
#spring.datasource.max-idle=8
#spring.datasource.min-idle=8
#spring.datasource.initial-size=20

编写实体类

package com.example.springboot.mybatis.entity;

public class User {
   private String id;

   private String username;

   private String password;

   private String email;

   /**
    * 是否可用(0禁用,1可用)
    */
   private Integer useable;

   /**
    * 创建时间
    */
   private String addtime;

   /**
    * 登陆时间
    */
   private String logintime;

   /**
    * 登陆IP
    */
   private String loginip;

}

编写dao数据库操作类

package com.example.springboot.mybatis.dao;

import com.example.springboot.mybatis.entity.User;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import java.util.List;


/**
 * 基于注解方式编写sql语句，开发中不适用，维护成本太高
 */
public interface UserDaoMapper {

   @Select("select id,username as username,password from t_user where id=#{id}")
   public User getUserById(Integer id);

   
   @Select("select id,username as username,password from t_user where username=#{name}")
   public List<User> getUserByPage(String name);
// 自增长id,使用options配置返回id值
// @Options(useGeneratedKeys=true,keyProperty="id",keyColumn="id")
   @Insert("insert into t_user(id,username,password) values(#{id},#{username},#{password})")
   public void saveUser(User user);
}

编写service类

package com.example.springboot.mybatis.service;

import com.example.springboot.mybatis.dao.UserDaoMapper;
import com.example.springboot.mybatis.entity.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;

/**
* @desc 通过注解方式查询数据库
* @Author wangsh
* @date 2018/5/5 23:12
* @return 
*/
@Service
public class UserService {

   @Autowired
   private UserDaoMapper userDaoMapper;

   public User getUserById(Integer id) {
      return userDaoMapper.getUserById(id);
   }

   public List<User> getUserByPage(String name) {
      return userDaoMapper.getUserByPage(name);
   }

   public void saveUser(User user) {
      userDaoMapper.saveUser(user);
   }
}

编写controller类

package com.example.springboot.mybatis.web;

import com.example.springboot.mybatis.entity.User;
import com.example.springboot.mybatis.service.UserService;
import com.example.springboot.mybatis.service.UserService2;
import com.example.springboot.mybatis.util.UUIDUtil;
import com.github.pagehelper.PageHelper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;

/**
 * @desc mybatis 操作数据库查询示例
 * @Author wangsh
 * @date 2018/5/5 23:18
 * @return
 */
@RestController
@RequestMapping("/user")
public class UserController {

   /**
    * 通过注解方式查询数据库
    */
   @Autowired
   private UserService userService;

   @RequestMapping("/getUserById")
   @ResponseBody
   public User getUserById(Integer id) {
      User User = userService.getUserById(id);
      return User;
   }

   @RequestMapping("/getUserByPage")
   @ResponseBody
   public List<User> getUserByPage(String name) {
      // 设置分页
      PageHelper.startPage(1, 2);
      List<User> users = userService.getUserByPage(name);
      return users;
   }

   @RequestMapping("/save")
   @ResponseBody
   public User save() {
      User user = new User();
      user.setId(UUIDUtil.getUUID());
      user.setUsername("lisi");
      user.setPassword("lisi");
      userService.saveUser(user);
      return user;
   }
}

编写启动服务类

启动完成如下：

数据库表：

通过浏览器访问： http://localhost:8080//user/getUserById?id=8376，返回结果表示操作数据库成功