懒人必备-代码生成器------mybatis-generator

代码生成器mybatis-generator

mybatis-generator是mybatis提供的一个代码生成工具，用于生成简单的CRUD代码，详情请见官网：
https://mybatis.org/generator/

废话不多说，直接来讲解怎么使用mybatis-generator
新建springBoot项目

项目详情

后面我们手动添加maven依赖，这里就不选择相关依赖


添加依赖：

		<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- mybatis -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.3</version>
        </dependency>
        <!-- MyBatis 生成器 -->
        <dependency>
            <groupId>org.mybatis.generator</groupId>
            <artifactId>mybatis-generator-core</artifactId>
            <version>1.3.7</version>
        </dependency>
        <!--Mysql数据库驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.18</version>
        </dependency>

mybatis的依赖可以直接换成MyBatis分页插件的依赖，在与SpringBoot整合时，只要整合了PagerHelper就自动整合了MyBatis，所以根据个人需求，这里只作为演示Demo，选用mybatis依赖。
项目相关配置：

server:
  port: 8002

spring:
  datasource:
  # 自己的数据库相关信息，用户名和密码等
    url: jdbc:mysql://localhost:3306/blog?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai
    username: root
    password: 123456

mybatis:
  mapper-locations:
    - classpath:mapper/*.xml

项目代码结构：

相关具体文件：
generatorConfig.xml

<?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.properties"/>
    <context id="MySqlContext" targetRuntime="MyBatis3" defaultModelType="flat">
        <property name="beginningDelimiter" value="`"/>
        <property name="endingDelimiter" value="`"/>
        <property name="javaFileEncoding" value="UTF-8"/>
        <!-- 为模型生成序列化方法-->
        <plugin type="org.mybatis.generator.plugins.SerializablePlugin"/>
        <!-- 为生成的Java模型创建一个toString方法 -->
        <plugin type="org.mybatis.generator.plugins.ToStringPlugin"/>
        <!--可以自定义生成model的代码注释-->
        <commentGenerator type="com.mybatisgenerator.example.mybatisgeneratordemo.mbg.CommentGenerator">
            <!-- 是否去除自动生成的注释 true：是 ： false:否 -->
            <property name="suppressAllComments" value="true"/>
            <property name="suppressDate" value="true"/>
            <property name="addRemarkComments" value="true"/>
        </commentGenerator>
        <!--配置数据库连接-->
        <jdbcConnection driverClass="${jdbc.driverClass}"
                        connectionURL="${jdbc.connectionURL}"
                        userId="${jdbc.userId}"
                        password="${jdbc.password}">
            <!--解决mysql驱动升级到8.0后不生成指定数据库代码的问题-->
            <property name="nullCatalogMeansCurrent" value="true" />
        </jdbcConnection>
        <!--指定生成model的路径-->
        <javaModelGenerator targetPackage="com.mybatisgenerator.example.mybatisgeneratordemo.Entities" targetProject="mybatis-generator-demo\src\main\java"/>
        <!--指定生成mapper.xml的路径-->
        <sqlMapGenerator targetPackage="mapper" targetProject="mybatis-generator-demo\src\main\java"/>
        <!--指定生成mapper接口的的路径-->
        <javaClientGenerator type="XMLMAPPER" targetPackage="com.mybatisgenerator.example.mybatisgeneratordemo.dao"
                             targetProject="mybatis-generator-demo\src\main\java"/>
        <!--生成全部表tableName设为%-->
        <table tableName="%">
            <generatedKey column="id" sqlStatement="MySql" identity="true"/>
        </table>
    </context>
</generatorConfiguration>

generator.properties

jdbc.driverClass=com.mysql.cj.jdbc.Driver
jdbc.connectionURL=jdbc:mysql://localhost:3306/blog?useUnicode=true&characterEncoding=utf-8&useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=Asia/Shanghai
jdbc.userId=root
jdbc.password=123456

CommentGenerator.java

package com.mybatisgenerator.example.mybatisgeneratordemo.mbg;

import org.mybatis.generator.api.IntrospectedColumn;
import org.mybatis.generator.api.IntrospectedTable;
import org.mybatis.generator.api.dom.java.Field;
import org.mybatis.generator.internal.DefaultCommentGenerator;
import org.mybatis.generator.internal.util.StringUtility;

import java.util.Properties;

/**
 * 自定义注释生成器
 * Created by macro on 2018/4/26.
 */
public class CommentGenerator extends DefaultCommentGenerator {
    private boolean addRemarkComments = false;

    /**
     * 设置用户配置的参数
     */
    @Override
    public void addConfigurationProperties(Properties properties) {
        super.addConfigurationProperties(properties);
        this.addRemarkComments = StringUtility.isTrue(properties.getProperty("addRemarkComments"));
    }

    /**
     * 给字段添加注释
     */
    @Override
    public void addFieldComment(Field field, IntrospectedTable introspectedTable,
                                IntrospectedColumn introspectedColumn) {
        String remarks = introspectedColumn.getRemarks();
        //根据参数和备注信息判断是否添加备注信息
        if (addRemarkComments && StringUtility.stringHasValue(remarks)) {
            addFieldJavaDoc(field, remarks);
        }
    }

    /**
     * 给model的字段添加注释
     */
    private void addFieldJavaDoc(Field field, String remarks) {
        //文档注释开始
        field.addJavaDocLine("/**");
        //获取数据库字段的备注信息
        String[] remarkLines = remarks.split(System.getProperty("line.separator"));
        for (String remarkLine : remarkLines) {
            field.addJavaDocLine(" * " + remarkLine);
        }
        addJavadocTag(field, false);
        field.addJavaDocLine(" */");
    }

}

package com.mybatisgenerator.example.mybatisgeneratordemo.mbg;

import org.mybatis.generator.api.MyBatisGenerator;
import org.mybatis.generator.config.Configuration;
import org.mybatis.generator.config.xml.ConfigurationParser;
import org.mybatis.generator.internal.DefaultShellCallback;

import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

/**
 * 用于生产MBG的代码
 * Created by macro on 2018/4/26.
 */
public class Generator {
    public static void main(String[] args) throws Exception {
        //MBG 执行过程中的警告信息
        List<String> warnings = new ArrayList<String>();
        //当生成的代码重复时，覆盖原代码
        boolean overwrite = true;
        //读取我们的 MBG 配置文件
        InputStream is = Generator.class.getResourceAsStream("/generatorConfig.xml");
        ConfigurationParser cp = new ConfigurationParser(warnings);
        Configuration config = cp.parseConfiguration(is);
        is.close();

        DefaultShellCallback callback = new DefaultShellCallback(overwrite);
        //创建 MBG
        MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
        //执行生成代码
        myBatisGenerator.generate(null);
        //输出警告信息
        for (String warning : warnings) {
            System.out.println(warning);
        }
    }
}

运行Generator结果：


然后你就不用在烦基础的CRUD了，只需要写相关定制的sql就行了！