springboot_mybatis

mybatis

• 引入啓動器

  <dependency>
      <groupId>org.mybatis.spring.boot</groupId>
      <artifactId>mybatis-spring-boot-starter</artifactId>
      <version>1.3.2</version>
  </dependency>
  

• 添加數據源與連接池

  <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-jdbc</artifactId>
  </dependency>
  
  
  <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.47</version>
  </dependency>
  
  

• yml配置

  spring:
    datasource:
      driver-class-name: com.mysql.jdbc.Driver
      username: root
      password: 990801lxq
      url: jdbc:mysql://localhost:3306/mybage?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
  
  
  mybatis:
    configuration:
      map-underscore-to-camel-case: true  #開啓駝峯命名
    type-aliases-package: cn.guoke.pojo   #別名
    mapper-locations: mapper/*.xml        #xml
  
  

• 配置掃描接口

  package cn.guoke;
  
  import org.mybatis.spring.annotation.MapperScan;
  import org.springframework.boot.SpringApplication;
  import org.springframework.boot.autoconfigure.SpringBootApplication;
  
  @SpringBootApplication
  @MapperScan("cn.guoke.mapper")
  public class Springboot2Application {
  
      public static void main(String[] args) {
          SpringApplication.run(Springboot2Application.class, args);
      }
  
  }
  

使用通用Mapper操作數據庫

• 引入Mapper

  在引入通用mapper後數據庫與mybatis就不需要引入了 ，只需要引入數據庫驅動就可以了，且會開啓駝峯命名

  <dependency>
      <groupId>tk.mybatis</groupId>
      <artifactId>mapper-spring-boot-starter</artifactId>
      <version>2.1.5</version>
  </dependency>
  
  

• 數據庫驅動

  <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.47</version>
  </dependency>
  
  

• 編寫實體類

  package cn.guoke;
  
  
  import lombok.AllArgsConstructor;
  import lombok.Data;
  import lombok.NoArgsConstructor;
  
  @Data
  @AllArgsConstructor
  @NoArgsConstructor
  public class User {
      private String id;
      private String name;
      private String pwd;
  }
  
  

• 編寫接口繼承Mapper

  package cn.guoke.mapper;
  
  
  import cn.guoke.User;
  import tk.mybatis.mapper.common.Mapper;
  
  public interface UserMapper extends Mapper<User> {
  
  }
  
  

• 在啓動處修改import tk.mybatis.spring.annotation.MapperScan;

  package cn.guoke;
  
  
  import org.springframework.boot.SpringApplication;
  import org.springframework.boot.autoconfigure.SpringBootApplication;
  import tk.mybatis.spring.annotation.MapperScan;
  
  @SpringBootApplication
  @MapperScan("cn.guoke.mapper")
  public class Springboot2Application {
  
      public static void main(String[] args) {
          SpringApplication.run(Springboot2Application.class, args);
      }
  
  }
  
  

• 使用通用Mapper的常用註解

  • @Table(name = "user") 表名
  • @Id 主鍵
  • @KeySql(useGeneratedKeys = true) 自增
  • @Transient 不是sql的字段

• test

  package cn.guoke;
  
  
  import cn.guoke.mapper.UserMapper;
  import cn.guoke.pojo.User;
  import org.junit.runner.RunWith;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.boot.test.context.SpringBootTest;
  import org.springframework.test.context.junit4.SpringRunner;
  
  @RunWith(SpringRunner.class)
  @SpringBootTest
  public class Test {
  
      @Autowired
      private UserMapper userMapper;
  
      @org.junit.Test
      public void test_01(){
          User user = userMapper.selectByPrimaryKey(1);
          System.out.println(user);
      }
  }