3 Star 18 Fork 2

MyBatis-Flex / MyBatis-Flex-Kotlin

Create your Gitee Account
Explore and code with more than 12 million developers,Free private repositories !:)
Sign up
Clone or Download
contribute
Sync branch
Cancel
Notice: Creating folder will generate an empty file .keep, because not support in Git
Loading...
readme.md
Apache-2.0

基于 Kotlin 扩展 Mybatis-Flex

MyBatis-Flex-Kotlin 基于 Mybatis-Flex 的 Kotlin 扩展模块,方便 Kotlin 开发者使用 MyBatis-Flex 进行开发

它继承了 Mybatis-Flex 轻量的特性,同时拥有 Kotlin 特有的扩展方法、中缀表达式与DSL等语法支持, 使其拥有了更高的灵活性。让我们可以更加轻松的在 Kotlin 中使用 Mybaits-Flex 所带来的开发效率和开发体验。

特征

  • 轻量:只基于 Mybatis-Flex 核心库 ,只做扩展不做改变
  • 简明:使用 DSL 让查询语句更加简单明了
  • 快捷:结合 Kotlin 特性快速对数据库进行操作

亮点

  • 快速构建启动:通过DSL➕重载运算符,快速配置 MybatisFlexBootstrap 实例并启动:

    runFlex {
        // 配置数据源 相当于 setDataSource(dataSource)
        +dataSource
        // 配置Mapper 相当于 addMapper(AccountMapper::class.java)
        +AccountMapper::class
        // 配置日志输出 相当于 setLogImpl(StdOutImpl::class.java)
        logImpl = StdOutImpl::class
      }
  • 快速查询数据:通过DSL➕泛型快速编写查询语句并查询: (快速查询提供三个函数:all, filter 和 query )

    • all<实体类>() 查泛型对应的表的所有数据
    • filter<实体类>(vararg KProperty<*>, ()->QueryCondition) 按条件查泛型对应的表的数据
    • query<实体类>(QueryScope.()->Unit) 较复杂查泛型对应的表的数据 (如: 分组,排序等)
  • 简明地构建查询:通过中缀表达式➕扩展方法能更加简单明了的构建条件:

    • 【对比原生】

      • 原生

          val queryWrapper = QueryWrapper.create()
              .select(QueryColumn("id"), QueryColumn("user_name"))
              .where(QueryColumn("age").isNotNull()).and(QueryColumn("age").ge(17))
              .orderBy(QueryColumn("id").desc())
          mapper<AccountMapper>().selectListByQuery(queryWrapper)
      • 扩展后

          // 无需注册Mapper与APT/KSP即可查询操作
          val accountList: List<Account> = query {
              select(Account::id, Account::userName)
              where(Account::age.isNotNull) and { Account::age ge 17 } orderBy -Account::id
          }

      执行的SQL:

       SELECT `id`, `user_name` FROM `tb_account` WHERE `age` IS NOT NULL  AND `age` >= 17 ORDER BY `id` DESC
    • 【条件优化】

      • 例如: 查询属性是否在一个连续的区间时,会自动将 IN 转为 BETWEEN 调用
         filter<Account> { Account::age `in` (17..19) }
        执行的SQL:
        SELECT * FROM `tb_account` WHERE `age` BETWEEN  17 AND 19
      • 例如: 构建多属性组合 IN (最多支持三个属性)
        filter<Account> {
          (Account::id to Account::userName to Account::age).inTriple(
              1 to "张三" to 18,
              2 to "李四" to 19,
          )
        }
        执行的SQL:
        SELECT * FROM `tb_account`
        WHERE (`id` = 1 AND `user_name` = '张三' AND `age` = 18) 
           OR (`id` = 2 AND `user_name` = '李四' AND `age` = 19)
  • 摆脱APT: 使用扩展方法摆脱对 APT(注解处理器) 的使用,直接使用属性引用让代码更加灵活优雅:

    使用APT: ACCOUNT.ID eq 1 ,使用属性引用: Account::id eq 1

    (少依赖一个模块且不用开启注解处理器功能)

  • 属性类型约束:使用泛型➕扩展方法对操作的属性进行类型约束:

    如: Account 中 age 属性为 Int 类型

    那么使用between时后续参数也必须是Int: Account::age between (17 to 19)

    而如果写成String:Account::age between ("17" to "19")则会报错提醒

快速开始

在开始之前,我们假定您已经:

  • 熟悉 Kotlin 环境配置及其开发
  • 熟悉 关系型 数据库,比如 MySQL
  • 熟悉 Kotlin 构建工具,比如 Gradle、Maven

本文档涉及到的 演示源码 已经全部上传 在开始之前,您也可以先下载到本地,导入到 idea 开发工具后,在继续看文档。

Mybatis-Flex源项目 中所介绍的功能本文档不再过多赘述建议,本文档只对 Mybatis-Flex 在 Kotlin 中特有的用法进行介绍

Hello World 文档

第 1 步:创建 Kotlin 项目,并添加 Kotlin 的扩展依赖

如何创建 Kotlin 项目可参考 Kotlin官方文档

需要添加的主要依赖:

【Kotlin】

dependencies {
  //kotlin扩展库
  implementation("com.mybatis-flex:mybatis-flex-kotlin-extensions:1.0.6")
  //核心库
  implementation("com.mybatis-flex:mybatis-flex-core:$version")
}

【Maven】

<dependencies>
  <!--kotlin扩展库-->
  <dependency>
    <groupId>com.mybatis-flex</groupId>
    <artifactId>mybatis-flex-kotlin-extensions</artifactId>
    <version>1.0.6</version>
  </dependency>
  <!--核心库-->
  <dependency>
    <groupId>com.mybatis-flex</groupId>
    <artifactId>mybatis-flex-core</artifactId>
    <version>${mybatis-flex-core.version}</version>
  </dependency>
</dependencies>

第 2 步:创建数据库表与配置数据源

请参考 源项目快速开始 创建数据库表与配置数据源, 或者使用演示源码中的内嵌数据库快速体验

第 3 步:编写实体类

@Table("tb_account")
data class Account(
  @Id var id: Int = -1,
  var userName: String? = null,
  var age: Int? = null,
  var birthday: Date? = null,
)
  • 使用 @Table("tb_account") 设置实体类与表名的映射关系
  • 使用 @Id 标识主键

⚠️ 最好不要写成 data class ,否则没有无参构造某些情况下会报错; 如有需要可以安装官方 noArg 插件

第 4 步:开始使用

添加测试类,进行功能测试:

  fun main() {
  // 加载数据源(为了方便演示这里使用了演示源码中的内嵌数据源)
  val dataSource: DataSource = EmbeddedDatabaseBuilder().run {
    setType(EmbeddedDatabaseType.H2)
    addScript("schema.sql")
    addScript("data-kt.sql")
    build()
  }
  // 启动并配入数据源
  runFlex { +dataSource }
  val start = Date.from(Instant.parse("2020-01-10T00:00:00Z"))
  val end = Date.from(Instant.parse("2020-01-12T00:00:00Z"))
  // 查泛型对应的表的所有数据
  all<Account>().forEach(::println)
  // 条件过滤查询并打印
  filter<Account> {
    (Account::id.isNotNull)
      .and { (Account::id to Account::userName).inPair(1 to "张三", 2 to "李四") }
      .and(Account::age.`in`(17..19) or { Account::birthday between (start to end) })
  }.forEach(::println)
}

执行的SQL:

  SELECT `age`, `birthday`, `id`, `user_name`
  FROM `tb_account`
  SELECT `age`, `birthday`, `id`, `user_name`
  FROM `tb_account`
  WHERE `id` IS NOT NULL
    AND (`id` = 1 AND `user_name` = '张三' OR (`id` = 2 AND `user_name` = '李四'))
    AND (`age` BETWEEN 17 AND 19 OR `birthday` BETWEEN '2020-01-10 08:00:00' AND '2020-01-12 08:00:00')

控制台输出:

Account(id=1, userName="张三", birthday="2020-01-11 00:00:00.0", age=18)
Account(id=2, userName="李四", birthday="2021-03-21 00:00:00.0", age=19)

更多使用

Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. Definitions. "License" shall mean the terms and conditions for use, reproduction, and distribution as defined by Sections 1 through 9 of this document. "Licensor" shall mean the copyright owner or entity authorized by the copyright owner that is granting the License. "Legal Entity" shall mean the union of the acting entity and all other entities that control, are controlled by, or are under common control with that entity. For the purposes of this definition, "control" means (i) the power, direct or indirect, to cause the direction or management of such entity, whether by contract or otherwise, or (ii) ownership of fifty percent (50%) or more of the outstanding shares, or (iii) beneficial ownership of such entity. "You" (or "Your") shall mean an individual or Legal Entity exercising permissions granted by this License. "Source" form shall mean the preferred form for making modifications, including but not limited to software source code, documentation source, and configuration files. "Object" form shall mean any form resulting from mechanical transformation or translation of a Source form, including but not limited to compiled object code, generated documentation, and conversions to other media types. "Work" shall mean the work of authorship, whether in Source or Object form, made available under the License, as indicated by a copyright notice that is included in or attached to the work (an example is provided in the Appendix below). "Derivative Works" shall mean any work, whether in Source or Object form, that is based on (or derived from) the Work and for which the editorial revisions, annotations, elaborations, or other modifications represent, as a whole, an original work of authorship. For the purposes of this License, Derivative Works shall not include works that remain separable from, or merely link (or bind by name) to the interfaces of, the Work and Derivative Works thereof. "Contribution" shall mean any work of authorship, including the original version of the Work and any modifications or additions to that Work or Derivative Works thereof, that is intentionally submitted to Licensor for inclusion in the Work by the copyright owner or by an individual or Legal Entity authorized to submit on behalf of the copyright owner. For the purposes of this definition, "submitted" means any form of electronic, verbal, or written communication sent to the Licensor or its representatives, including but not limited to communication on electronic mailing lists, source code control systems, and issue tracking systems that are managed by, or on behalf of, the Licensor for the purpose of discussing and improving the Work, but excluding communication that is conspicuously marked or otherwise designated in writing by the copyright owner as "Not a Contribution." "Contributor" shall mean Licensor and any individual or Legal Entity on behalf of whom a Contribution has been received by Licensor and subsequently incorporated within the Work. 2. Grant of Copyright License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare Derivative Works of, publicly display, publicly perform, sublicense, and distribute the Work and such Derivative Works in Source or Object form. 3. Grant of Patent License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer the Work, where such license applies only to those patent claims licensable by such Contributor that are necessarily infringed by their Contribution(s) alone or by combination of their Contribution(s) with the Work to which such Contribution(s) was submitted. If You institute patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that the Work or a Contribution incorporated within the Work constitutes direct or contributory patent infringement, then any patent licenses granted to You under this License for that Work shall terminate as of the date such litigation is filed. 4. Redistribution. You may reproduce and distribute copies of the Work or Derivative Works thereof in any medium, with or without modifications, and in Source or Object form, provided that You meet the following conditions: (a) You must give any other recipients of the Work or Derivative Works a copy of this License; and (b) You must cause any modified files to carry prominent notices stating that You changed the files; and (c) You must retain, in the Source form of any Derivative Works that You distribute, all copyright, patent, trademark, and attribution notices from the Source form of the Work, excluding those notices that do not pertain to any part of the Derivative Works; and (d) If the Work includes a "NOTICE" text file as part of its distribution, then any Derivative Works that You distribute must include a readable copy of the attribution notices contained within such NOTICE file, excluding those notices that do not pertain to any part of the Derivative Works, in at least one of the following places: within a NOTICE text file distributed as part of the Derivative Works; within the Source form or documentation, if provided along with the Derivative Works; or, within a display generated by the Derivative Works, if and wherever such third-party notices normally appear. The contents of the NOTICE file are for informational purposes only and do not modify the License. You may add Your own attribution notices within Derivative Works that You distribute, alongside or as an addendum to the NOTICE text from the Work, provided that such additional attribution notices cannot be construed as modifying the License. You may add Your own copyright statement to Your modifications and may provide additional or different license terms and conditions for use, reproduction, or distribution of Your modifications, or for any such Derivative Works as a whole, provided Your use, reproduction, and distribution of the Work otherwise complies with the conditions stated in this License. 5. Submission of Contributions. Unless You explicitly state otherwise, any Contribution intentionally submitted for inclusion in the Work by You to the Licensor shall be under the terms and conditions of this License, without any additional terms or conditions. Notwithstanding the above, nothing herein shall supersede or modify the terms of any separate license agreement you may have executed with Licensor regarding such Contributions. 6. Trademarks. This License does not grant permission to use the trade names, trademarks, service marks, or product names of the Licensor, except as required for reasonable and customary use in describing the origin of the Work and reproducing the content of the NOTICE file. 7. Disclaimer of Warranty. Unless required by applicable law or agreed to in writing, Licensor provides the Work (and each Contributor provides its Contributions) on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. You are solely responsible for determining the appropriateness of using or redistributing the Work and assume any risks associated with Your exercise of permissions under this License. 8. Limitation of Liability. In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall any Contributor be liable to You for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising as a result of this License or out of the use or inability to use the Work (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if such Contributor has been advised of the possibility of such damages. 9. Accepting Warranty or Additional Liability. While redistributing the Work or Derivative Works thereof, You may choose to offer, and charge a fee for, acceptance of support, warranty, indemnity, or other liability obligations and/or rights consistent with this License. However, in accepting such obligations, You may act only on Your own behalf and on Your sole responsibility, not on behalf of any other Contributor, and only if You agree to indemnify, defend, and hold each Contributor harmless for any liability incurred by, or claims asserted against, such Contributor by reason of your accepting any such warranty or additional liability. END OF TERMS AND CONDITIONS APPENDIX: How to apply the Apache License to your work. To apply the Apache License to your work, attach the following boilerplate notice, with the fields enclosed by brackets "{}" replaced with your own identifying information. (Don't include the brackets!) The text should be enclosed in the appropriate comment syntax for the file format. We also recommend that a file or class name and description of purpose be included on the same "printed page" as the copyright notice for easier identification within third-party archives. Copyright {yyyy} {name of copyright owner} Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

About

MyBatis-Flex 的 Kotlin 扩展。 expand collapse
Kotlin and 3 more languages
Apache-2.0
Cancel

Releases (1)

All

Contributors

All

Activities

Load More
can not load any more
1
https://gitee.com/mybatis-flex/mybatis-flex-kotlin.git
git@gitee.com:mybatis-flex/mybatis-flex-kotlin.git
mybatis-flex
mybatis-flex-kotlin
MyBatis-Flex-Kotlin
main

Search