springboot植入pagerHelper的超详细教程

简介

前面个已经讲过mybatis的批量更新操作。批量操作还有时分页查询，针对项目的完善性，来讲解一下分页工具的植入pagerHelper和tk.mybatis使用。其实官网已经有具体代码，代价有空可以多多参考官网操作。链接地址MyBatis-Spring-Boot

技术方案

maven jar导入

查看官方说明引入依赖，如下：

<!--mybatis-->
<dependency>
  <groupId>org.mybatis.spring.boot</groupId>
  <artifactId>mybatis-spring-boot-starter</artifactId>
  <version>1.3.1</version>
</dependency>
<!--mapper-->
<dependency>
  <groupId>tk.mybatis</groupId>
  <artifactId>mapper-spring-boot-starter</artifactId>
  <version>1.2.4</version>
</dependency>
<!--pagehelper-->
<dependency>
  <groupId>com.github.pagehelper</groupId>
  <artifactId>pagehelper-spring-boot-starter</artifactId>
  <version>1.2.3</version>
</dependency>

maven plugin配置

引入完jar依赖之后，配置plugin插件，插件时根据maven来识别的，可以直接拷贝官网的配置即可，如下：

<plugin>
        <groupId>org.mybatis.generator</groupId>
        <artifactId>mybatis-generator-maven-plugin</artifactId>
        <version>1.3.2</version>
        <configuration>
          <configurationFile>${basedir}/src/main/resources/generator/generatorConfig.xml</configurationFile>
          <overwrite>true</overwrite>
          <verbose>true</verbose>
        </configuration>
        <dependencies>
          <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>${mysql.version}</version>
          </dependency>
          <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper-generator</artifactId>
            <version>1.0.0</version>
          </dependency>
        </dependencies>
      </plugin>

配置generatorConfig.xml

根据自己喜欢，可以定制化配置generatorConfig.xml，下面是我个人基本配置，更多配置说明，请查看官方说明MyBatis Generator 详解

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration
    PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
    "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">

<generatorConfiguration>
  <properties resource="generator/application-dev.properties"/>

  <context id="Mysql" targetRuntime="MyBatis3Simple" defaultModelType="flat">
    <property name="beginningDelimiter" value="`"/>
    <property name="endingDelimiter" value="`"/>
    <plugin type="tk.mybatis.mapper.generator.MapperPlugin">
      <property name="mappers" value="com.lgh.common.util.MyMapper"/>
    </plugin>

    <jdbcConnection driverClass="${spring.datasource.driver-class-name}"
            connectionURL="${spring.datasource.url}"
            userId="${spring.datasource.username}"
            password="${spring.datasource.password}">
    </jdbcConnection>

    <javaModelGenerator targetPackage="com.lgh.model" targetProject="src/main/java"/>

    <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources"/>

    <javaClientGenerator targetPackage="com.lgh.mapper" targetProject="src/main/java"
               type="XMLMAPPER"/>

    <!-- 数据库表 以及实体类命名 -->
    <!-- <table schema="CL_DEMO" tableName="tb_user" domainObjectName="User"
        enableCountByExample="false" enableDeleteByExample="false"
        enableSelectByExample="false" enableUpdateByExample="false"
        selectByExampleQueryId="false" />
    <table schema="CL_DEMO" tableName="tb_role" domainObjectName="Role"
        enableCountByExample="false" enableDeleteByExample="false"
        enableSelectByExample="false" enableUpdateByExample="false"
        selectByExampleQueryId="false" />
    <table schema="CL_DEMO" tableName="tb_menu" domainObjectName="Menu"
        enableCountByExample="false" enableDeleteByExample="false"
        enableSelectByExample="false" enableUpdateByExample="false"
        selectByExampleQueryId="false" />
    <table schema="CL_DEMO" tableName="tb_resource" domainObjectName="Resource"
        enableCountByExample="false" enableDeleteByExample="false"
        enableSelectByExample="false" enableUpdateByExample="false"
        selectByExampleQueryId="false" />
    <table schema="CL_DEMO" tableName="user_role" domainObjectName="UserRole"
        enableCountByExample="false" enableDeleteByExample="false"
        enableSelectByExample="false" enableUpdateByExample="false"
        selectByExampleQueryId="false" />
    <table schema="CL_DEMO" tableName="role_menu" domainObjectName="RoleMenu"
        enableCountByExample="false" enableDeleteByExample="false"
        enableSelectByExample="false" enableUpdateByExample="false"
        selectByExampleQueryId="false" />
    <table schema="CL_DEMO" tableName="menu_resource" domainObjectName="MenuResource"
        enableCountByExample="false" enableDeleteByExample="false"
        enableSelectByExample="false" enableUpdateByExample="false"
        selectByExampleQueryId="false" />
    <table schema="CL_DEMO" tableName="role_resource" domainObjectName="RoleResource"
        enableCountByExample="false" enableDeleteByExample="false"
        enableSelectByExample="false" enableUpdateByExample="false"
        selectByExampleQueryId="false" />
    <table schema="CL_DEMO" tableName="logon" domainObjectName="Logon"
        enableCountByExample="false" enableDeleteByExample="false"
        enableSelectByExample="false" enableUpdateByExample="false"
        selectByExampleQueryId="false" />-->
  </context>
</generatorConfiguration>

测试样例

在这里插入图片描述

点击mybatis-generator:generate即可生成对象和映射文件，具体如上图

一般分页个人喜好建议用jdk8的lambda表达式，如：//对应的lambda用法 pageInfo = PageHelper.startPage(1, 10).doSelectPageInfo(() -> userMapper.selectGroupBy());，更多请查看官网分页使用方式

总结&反思

基本操作对象，我们不要再手动一个一个的写啦，直接用mybatis插件生成。基本curd不要再自己编写xml，直接用tk.mysql操作即可。一对多情况，分页无法实现谨慎使用

源码地址

github

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