MyBatis plus自动生成代码

1.pom文件配置

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.5.3</version>
</dependency>
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-generator</artifactId>
    <version>3.5.3</version>
</dependency>
<dependency>

温馨提示：

从上面的pom.xml配置可以看出，使用的mybatis版本为：3.5.3。不同的版本其实现自动生成代码的方式不同，特别是3.5.1及其以上的版本和之前的版本有很大区别。

这是官网中的说明：

2.工具类具体代码实现

package com.mycompany.common.utils;

import com.au.sa.common.services.CommonAbstractService;
import com.baomidou.mybatisplus.generator.FastAutoGenerator;
import com.baomidou.mybatisplus.generator.config.OutputFile;
import com.baomidou.mybatisplus.generator.engine.FreemarkerTemplateEngine;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang.StringUtils;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.util.Collections;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * @author xiaohuihui
 * @creteTime 2024-03-16 10:11
 * @description
 */
@Slf4j
public class MyBatisAutoGeneratorUtil {
    /**
     * 数据库连接串
     */
    public static final String DB_URL = "jdbc:mysql://{ip}:{port}/{dbName}?useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai&useSSL=true&autoReconnect=true";
    /**
     * 数据库连接用户名
     */
    public static final String DB_USER_NAME = "username";
    /**
     * 数据库连接密码
     */
    public static final String DB_PASSWORD = "*****";
    /**
     * 注释的作者
     */
    public static final String AUTHOR = "xiaohuihui";
    /**
     * 公共父类实体类中含有的字段
     */
    private static final String[] SUPPER_ENTITY_CONTAINS_FIELD = {"delete_flag", "version_num", "creation_date", "created_by", "last_update_date", "last_updated_by"};
    /**
     * 生成的代码默认输出文件目录
     */
    private static final String DEFAULT_OUT_PUT_DIR = "D://MyBatisPlusAutoGeneratorDir";
    private static final String RESP_OUT_PUT_DIR = "D://MyBatisPlusAutoGeneratorDir";
    /**
     * 默认包名称
     */
    private static final String DEFAULT_PARENT_PACK = "com.au.sa.storeRebate";
    /**
     * 默认父级实体类全路径类 实体类继承的父类
     */
    private static final String BASE_SUPER_ENTITY_CLASS_NAME = "com.au.sa.storeRebate.common.entity.BaseDbEntity";
    /**
     * 要生成代码的表名
     */
    private static final String[] TABLE_NAMES = new String[]{"table_name"};


    public static void main(String[] args) {
        FastAutoGenerator.create(DB_URL, DB_USER_NAME, DB_PASSWORD).globalConfig(builder -> {
            builder.author(AUTHOR) // 设置作者
                    .enableSwagger() // 开启 swagger 模式
                    .outputDir(DEFAULT_OUT_PUT_DIR); // 指定输出目录
        }).packageConfig(builder -> {
            builder.parent("com.au.sa") // 设置父包名
                    .moduleName("storeRebate") // 设置父包模块名
                    .pathInfo(Collections.singletonMap(OutputFile.xml, DEFAULT_OUT_PUT_DIR)); // 设置mapperXml生成路径
        }).strategyConfig(builder -> {
            builder.addInclude(TABLE_NAMES) // 设置需要生成的表名
                    .entityBuilder()
                    .enableTableFieldAnnotation()
                    .enableLombok()
                    .enableFileOverride()
                    .superClass(BASE_SUPER_ENTITY_CLASS_NAME)
                    .controllerBuilder()
                    .superClass(CommonAbstractService.class)//Controller想要继承的父类
                    .enableHyphenStyle()
                    .enableRestStyle()
                    .enableFileOverride()
                    .formatFileName("%sController")
                    .serviceBuilder()
                    .enableFileOverride()
                    .formatServiceFileName("%sService")
                    .formatServiceImplFileName("%sServiceImpl")
                    .mapperBuilder()
                    .enableFileOverride()
                    .enableBaseResultMap()
                    .enableBaseColumnList()
                    .formatMapperFileName("%sDao");
        }).templateEngine(new FreemarkerTemplateEngine()) // 使用Freemarker引擎模板，默认的是Velocity引擎模板
                .execute();

        // 生成Vo对象。如果不需要生成前端返回resp对象，可以不加，这段是自己加的，不是MyBatis-Plus提供
        produceViewObject(false, TABLE_NAMES);

    }


    /**
     * 根据表名生成VO对象,用于mybatis-plus代码生成以后再生成
     *
     * @param isTablePrefix
     * @param tableNames
     */
    private static void produceViewObject(boolean isTablePrefix, String... tableNames) {
        for (int i = 0; i < tableNames.length; i++) {
            String tableName = tableNames[i];
            tableName = isTablePrefix ? tableName.substring(tableName.indexOf("_") + 1) : tableName;
            String outPutDir = RESP_OUT_PUT_DIR + "/" + (DEFAULT_PARENT_PACK.replace(".", "/")) + "/resp/";
            String baseFileName = underline2Camel(tableName, false);
            try {
                File outFile = new File(outPutDir);
                if (!outFile.exists()) {
                    outFile.mkdirs();
                }
                File voFile = new File(outFile, baseFileName + "Resp.java");
                if (!voFile.exists()) {
                    voFile.createNewFile();
                }
                BufferedReader reader = new BufferedReader(
                        new FileReader(DEFAULT_OUT_PUT_DIR + "/" + (DEFAULT_PARENT_PACK.replace(".", "/")) + "/entity/"
                                + baseFileName + ".java"));
                FileWriter fw = new FileWriter(voFile);
                String line = null;
                String description = null;
                String regex = "([\u4e00-\u9fa5]+)";
                while ((line = reader.readLine()) != null) {
                    Matcher matcher = Pattern.compile(regex).matcher(line); //匹配字段描述
                    if (matcher.find()) {
                        description = matcher.group(1);
                    }
                    // 将实体类中的entity变为Vo
                    int index = line.indexOf(baseFileName);
                    if (line.contains("package")) {
                        line = StringUtils.substringBeforeLast(line, ".") + ".resp;";
                    } else if (index > -1 && !line.contains("@ApiModel")) {
                        if (line.contains("+")) {
                            line = StringUtils.substring(line, 0, index + baseFileName.length()) + "{\" +"; //解决toString()
                        } else {
                            line = StringUtils.substring(line, 0, index + baseFileName.length()) + "{";
                        }
                        line = line.replace(baseFileName, baseFileName + "Resp");
                    } else if (line.contains("@TableName")) {
                        description = "";
                        continue;
                    } else if (line.contains("@TableField") || line.contains("@TableId")) {
                        boolean required = true;
                        for (String col : SUPPER_ENTITY_CONTAINS_FIELD) {
                            if (line.contains(col) && !StringUtils.equals("version_num", col)) {
                                required = false;
                                break;
                            }
                        }
                        description = "";
                        continue;
                    } else if (line.contains("@Accessors") || line.contains("@Override") || line.contains("@TableLogic") || line.contains("@Version")) {
                        continue;
                    }
                    line += "\r\n";
                    fw.write(line);
                }
                fw.close();
                reader.close();
            } catch (Exception e) {
                log.error(e.getMessage(), e);
            }
        }
    }

    /**
     * 下划线转驼峰法(默认小驼峰)
     *
     * @param line       源字符串
     * @param smallCamel 大小驼峰,是否为小驼峰(驼峰，第一个字符是大写还是小写)
     * @return 转换后的字符串
     */
    public static String underline2Camel(String line, boolean... smallCamel) {
        if (StringUtils.isBlank(line)) {
            return "";
        }
        StringBuffer sb = new StringBuffer();
        Pattern pattern = Pattern.compile("([A-Za-z\\d]+)(_)?");
        Matcher matcher = pattern.matcher(line);
        // 匹配正则表达式
        while (matcher.find()) {
            String word = matcher.group();
            // 当是true 或则是空的情况
            if ((smallCamel.length == 0 || smallCamel[0]) && matcher.start() == 0) {
                sb.append(Character.toLowerCase(word.charAt(0)));
            } else {
                sb.append(Character.toUpperCase(word.charAt(0)));
            }

            int index = word.lastIndexOf('_');
            if (index > 0) {
                sb.append(word.substring(1, index).toLowerCase());
            } else {
                sb.append(word.substring(1).toLowerCase());
            }
        }
        return sb.toString();
    }
}

3.相关配置说明

参考官网：MyBatis-Plus代码生成器配置

#数据库配置(DataSourceConfig)

#基础配置

new DataSourceConfig.Builder("jdbc:mysql://127.0.0.1:3306/mybatis-plus","root","123456")
    .build();

#可选配置

// 使用SQL查询的方式生成代码,属于旧的代码生成方式,通用性不是好,老的代码可以继续使用,适配数据库需要完成dbQuery和typeConvert的扩展,后期不再维护这种方式
new DataSourceConfig.Builder("jdbc:mysql://127.0.0.1:3306/mybatis-plus","root","123456")
    .dbQuery(new MySqlQuery())
    .schema("mybatis-plus")
    .typeConvert(new MySqlTypeConvert())
    .keyWordsHandler(new MySqlKeyWordsHandler())
    .databaseQueryClass(SQLQuery.class)
    .build();

// 使用元数据查询的方式生成代码,默认已经根据jdbcType来适配java类型,支持使用typeConvertHandler来转换需要映射的类型映射
new DataSourceConfig.Builder("jdbc:mysql://127.0.0.1:3306/mybatis-plus","root","123456")
    .schema("mybatis-plus")
    .keyWordsHandler(new MySqlKeyWordsHandler())
    .build();

#全局配置(GlobalConfig)

new GlobalConfig.Builder()
    .fileOverride()
    .outputDir("/opt/baomidou")
    .author("baomidou")
    .enableKotlin()
    .enableSwagger()
    .dateType(DateType.TIME_PACK)
    .commentDate("yyyy-MM-dd")
    .build();

#包配置(PackageConfig)

new PackageConfig.Builder()
    .parent("com.baomidou.mybatisplus.samples.generator")
    .moduleName("sys")
    .entity("po")
    .service("service")
    .serviceImpl("service.impl")
    .mapper("mapper")
    .xml("mapper.xml")
    .controller("controller")
    .other("other")
    .pathInfo(Collections.singletonMap(OutputFile.mapperXml, "D://"))
    .build();

#模板配置(TemplateConfig)

new TemplateConfig.Builder()
    .disable(TemplateType.ENTITY)
    .entity("/templates/entity.java")
    .service("/templates/service.java")
    .serviceImpl("/templates/serviceImpl.java")
    .mapper("/templates/mapper.java")
    .mapperXml("/templates/mapper.xml")
    .controller("/templates/controller.java")
    .build();

#注入配置(InjectionConfig)

new InjectionConfig.Builder()
    .beforeOutputFile((tableInfo, objectMap) -> {
        System.out.println("tableInfo: " + tableInfo.getEntityName() + " objectMap: " + objectMap.size());
    })
    .customMap(Collections.singletonMap("test", "baomidou"))
    .customFile(Collections.singletonMap("test.txt", "/templates/test.vm"))
    .build();

#策略配置(StrategyConfig)

new StrategyConfig.Builder()
    .enableCapitalMode()
    .enableSkipView()
    .disableSqlFilter()
    .likeTable(new LikeTable("USER"))
    .addInclude("t_simple")
    .addTablePrefix("t_", "c_")
    .addFieldSuffix("_flag")
    .build();

#Entity 策略配置

new StrategyConfig.Builder()
    .entityBuilder()
    .superClass(BaseEntity.class)
    .disableSerialVersionUID()
    .enableChainModel()
    .enableLombok()
    .enableRemoveIsPrefix()
    .enableTableFieldAnnotation()
    .enableActiveRecord()
    .versionColumnName("version")
    //.versionPropertyName("version") 
    .logicDeleteColumnName("deleted")
    //.logicDeletePropertyName("deleteFlag")
    .naming(NamingStrategy.no_change)
    .columnNaming(NamingStrategy.underline_to_camel)
    .addSuperEntityColumns("id", "created_by", "created_time", "updated_by", "updated_time")
    .addIgnoreColumns("age")
    .addTableFills(new Column("create_time", FieldFill.INSERT))
    .addTableFills(new Property("updateTime", FieldFill.INSERT_UPDATE))
    .idType(IdType.AUTO)
    .formatFileName("%sEntity")
    .build();

#Controller 策略配置

new StrategyConfig.Builder()
    .controllerBuilder()
    .superClass(BaseController.class)
    .enableHyphenStyle()
    .enableRestStyle()
    .formatFileName("%sAction")
    .build();

#Service 策略配置

new StrategyConfig.Builder()
    .serviceBuilder()
    .superServiceClass(BaseService.class)
    .superServiceImplClass(BaseServiceImpl.class)
    .formatServiceFileName("%sService")
    .formatServiceImplFileName("%sServiceImp")
    .build();

#Mapper 策略配置

new StrategyConfig.Builder()
    .mapperBuilder()
    .superClass(BaseMapper.class)
    .enableMapperAnnotation()
    .enableBaseResultMap()
    .enableBaseColumnList()
    .cache(MyMapperCache.class)
    .formatMapperFileName("%sDao")
    .formatXmlFileName("%sXml")
    .build();

#自定义模版支持(DTO\VO等)配置

#Freemarker模版支持(DTO\VO等)配置

/**
 * 代码生成器支持自定义[DTO\VO等]模版
 */
public final class EnhanceFreemarkerTemplateEngine extends FreemarkerTemplateEngine {

    @Override
    protected void outputCustomFile(@NotNull Map<String, String> customFile, @NotNull TableInfo tableInfo, @NotNull Map<String, Object> objectMap) {
        String entityName = tableInfo.getEntityName();
        String otherPath = this.getPathInfo(OutputFile.other);
        customFile.forEach((key, value) -> {
            String fileName = String.format(otherPath + File.separator + entityName + "%s", key);
            this.outputFile(new File(fileName), objectMap, value);
        });
    }
}

使用方式样例(其他细节参数请查看文档)

entityDTO.java.ftl 可参考源码内entity.java.ftl文件

FastAutoGenerator.create(url, username, password)
                .globalConfig(builder -> {
                    builder.author("abc") // 设置作者
                            .enableSwagger() // 开启 swagger 模式
                            .fileOverride() // 覆盖已生成文件
                            .disableOpenDir() //禁止打开输出目录
                            .outputDir(finalProjectPath + "/src/main/java"); // 指定输出目录
                })
                .packageConfig(builder -> {
                    builder.parent("com.baomidou.mybatisplus.samples") // 设置父包名
                            .moduleName("test") // 设置父包模块名
                            .entity("model.entity") //设置entity包名
                            .other("model.dto") // 设置dto包名
                            .pathInfo(Collections.singletonMap(OutputFile.xml, finalProjectPath + "/src/main/resources/mapper")); // 设置mapperXml生成路径

                })
                .injectionConfig(consumer -> {
                    Map<String, String> customFile = new HashMap<>();
                    // DTO
                    customFile.put("DTO.java", "/templates/entityDTO.java.ftl");
                    consumer.customFile(customFile);
                });