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Mybatis-Flex 第一个版本发布，一个优雅的 Mybatis 增强框架

日期：2023-03-01点击：773收藏

Mybatis-Flex 第一个版本发布，一个优雅的 Mybatis 增强框架。

特征

1、很轻量，整个框架只依赖 Mybatis 再无其他第三方依赖
2、Entity 类的基本增删改查、以及分页查询
3、Row 通用映射支持，可以无需实体类对数据库进行增删改查
4、支持多种数据库类型，自由通过方言持续扩展
5、支持联合主键，以及不同的主键内容生成策略
6、极其友好的 SQL 联动查询，IDE 自动提示不再担心出错
7、更多小惊喜

hello world

第一步：编写 Entity 实体类

 @Table("tb_account") public class Account {  @Id()  private Long id;  private String userName;  private Date birthday;  private int sex;  //getter setter }

第二步，编写 Mapper 类，并继承 BaseMapper

 public interface AccountMapper extends BaseMapper<Account> {  //只需定义 Mapper 接口即可，可以无任何内容。 }

第三步：开始查询数据

示例 1：查询 1 条数据

 class HelloWorld {  public static void main(String... args) {  HikariDataSource dataSource = new HikariDataSource();  dataSource.setJdbcUrl("jdbc:mysql://127.0.0.1:3306/mybatis-flex");  dataSource.setUsername("username");  dataSource.setPassword("password");  MybatisFlexBootstrap.getInstance()  .setDatasource(dataSource)  .addMapper(AccountMapper.class)  .start();  //示例1：查询 id=100 条数据  Account account = MybatisFlexBootstrap.getInstance()  .execute(AccountMapper.class, mapper ->  mapper.selectOneById(100)  );  } }

示例2：查询列表

 class HelloWorld {  public static void main(String... args) {  HikariDataSource dataSource = new HikariDataSource();  dataSource.setJdbcUrl("jdbc:mysql://127.0.0.1:3306/mybatis-flex");  dataSource.setUsername("username");  dataSource.setPassword("password");  MybatisFlexBootstrap.getInstance()  .setDatasource(dataSource)  .addMapper(AccountMapper.class)  .start();    //示例2：通过 QueryWrapper 构建条件查询数据列表  QueryWrapper query = QueryWrapper.create()  .select()  .from(ACCOUNT)  .where(ACCOUNT.ID.ge(100))  .and(ACCOUNT.USER_NAME.like("张").or(ACCOUNT.USER_NAME.like("李")));  // 执行 SQL：  // ELECT * FROM `tb_account`  // WHERE `tb_account`.`id` >= 100  // AND (`tb_account`.`user_name` LIKE '%张%' OR `tb_account`.`user_name` LIKE '%李%' )  List<Account> accounts = MybatisFlexBootstrap.getInstance()  .execute(AccountMapper.class, mapper ->  mapper.selectListByQuery(query)  );    } }

示例3：分页查询

 class HelloWorld {  public static void main(String... args) {  HikariDataSource dataSource = new HikariDataSource();  dataSource.setJdbcUrl("jdbc:mysql://127.0.0.1:3306/mybatis-flex");  dataSource.setUsername("username");  dataSource.setPassword("password");  MybatisFlexBootstrap.getInstance()  .setDatasource(dataSource)  .addMapper(AccountMapper.class)  .start();  // 示例3：分页查询  // 查询第 5 页，每页 10 条数据，通过 QueryWrapper 构建条件查询  QueryWrapper query = QueryWrapper.create()  .select()  .from(ACCOUNT)  .where(ACCOUNT.ID.ge(100))  .and(ACCOUNT.USER_NAME.like("张").or(ACCOUNT.USER_NAME.like("李")))  .orderBy(ACCOUNT.ID.desc());  // 执行 SQL：  // ELECT * FROM `tb_account`  // WHERE `tb_account`.`id` >= 100  // AND (`tb_account`.`user_name` LIKE '%张%' OR `tb_account`.`user_name` LIKE '%李%' )  // ORDER BY `tb_account`.`id` DESC  // LIMIT 40,10  Page<Account> accounts = MybatisFlexBootstrap.getInstance()  .execute(AccountMapper.class, mapper ->  mapper.paginate(5, 10, query)  );  } }

QueryWrapper 示例

select *

 QueryWrapper query=new QueryWrapper();  query.select().from(ACCOUNT) // SQL:  // SELECT * FROM tb_account

select columns

 QueryWrapper query=new QueryWrapper();  query.select(ACCOUNT.ID,ACCOUNT.USER_NAME).from(ACCOUNT) // SQL:  // SELECT tb_account.id, tb_account.user_name  // FROM tb_account

 QueryWrapper query=new QueryWrapper();  query.select(ACCOUNT.ALL_COLUMNS).from(ACCOUNT) // SQL:  // SELECT tb_account.id, tb_account.user_name, tb_account.birthday,  // tb_account.sex, tb_account.is_normal  // FROM tb_account

select functions

  QueryWrapper query=new QueryWrapper()  .select(ACCOUNT.ID  ,ACCOUNT.USER_NAME  ,max(ACCOUNT.BIRTHDAY)  ,avg(ACCOUNT.SEX).as("sex_avg"))  .from(ACCOUNT); // SQL:  // SELECT tb_account.id, tb_account.user_name,  // MAX(tb_account.birthday),  // AVG(tb_account.sex) AS sex_avg  // FROM tb_account

where

  QueryWrapper queryWrapper=QueryWrapper.create()  .select()  .from(ACCOUNT)  .where(ACCOUNT.ID.ge(100))  .and(ACCOUNT.USER_NAME.like("michael")); // SQL:  // SELECT * FROM tb_account  // WHERE tb_account.id >= ?  // AND tb_account.user_name LIKE ?

exists, not exists

  QueryWrapper queryWrapper=QueryWrapper.create()  .select()  .from(ACCOUNT)  .where(ACCOUNT.ID.ge(100))  .and(  exist(  selectOne().from(ARTICLE).where(ARTICLE.ID.ge(100))  )  ); // SQL:  // SELECT * FROM tb_account  // WHERE tb_account.id >= ?  // AND EXIST ( // SELECT 1 FROM tb_article WHERE tb_article.id >= ?  // )

and (...) or (...)

  QueryWrapper queryWrapper=QueryWrapper.create()  .select()  .from(ACCOUNT)  .where(ACCOUNT.ID.ge(100))  .and(ACCOUNT.SEX.eq(1).or(ACCOUNT.SEX.eq(2)))  .or(ACCOUNT.AGE.in(18,19,20).or(ACCOUNT.USER_NAME.like("michael"))); // SQL:  // SELECT * FROM tb_account  // WHERE tb_account.id >= ?  // AND (tb_account.sex = ? OR tb_account.sex = ? )  // OR (tb_account.age IN (?,?,?) OR tb_account.user_name LIKE ? )

group by

  QueryWrapper queryWrapper=QueryWrapper.create()  .select()  .from(ACCOUNT)  .groupBy(ACCOUNT.USER_NAME); // SQL:  // SELECT * FROM tb_account  // GROUP BY tb_account.user_name

having

  QueryWrapper queryWrapper=QueryWrapper.create()  .select()  .from(ACCOUNT)  .groupBy(ACCOUNT.USER_NAME)  .having(ACCOUNT.AGE.between(18,25)); // SQL:  // SELECT * FROM tb_account  // GROUP BY tb_account.user_name  // HAVING tb_account.age BETWEEN ? AND ?

jion

  QueryWrapper queryWrapper = QueryWrapper.create()  .select()  .from(ACCOUNT)  .leftJoin(ARTICLE).on(ACCOUNT.ID.eq(ARTICLE.ACCOUNT_ID))  .where(ACCOUNT.AGE.ge(10)); // SQL:  // SELECT * FROM tb_account  // LEFT JOIN tb_article  // ON tb_account.id = tb_article.account_id  // WHERE tb_account.age >= ?