Swagger 3.0 & MybatisPlus 主键BigDecimal 使用过程问题

PS：本来用的是2.x的，但是因为换了后端框架，导致版本不适配，于是调整到3.0

        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-boot-starter</artifactId>
            <version>3.0.0</version>
        </dependency>

由于由hibernate切换到了mybatisplus，导致主键的生成方式变化，使用Mybatisplus的代码生成器，自动生成的ID是BigDecimal 

    @TableId("ID")
    private BigDecimal id;

在使用Swagger接口文档中（http://xxx/swagger-ui/index.html）测试过程中发现BigDecimal 精度丢失，于是开始进行类型兼容（PS：接口文档id入参全改成String，自动处理，无需额外处理）

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.module.SimpleModule;
import com.fasterxml.jackson.databind.ser.std.ToStringSerializer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;

import java.math.BigDecimal;

@Configuration
public class JacksonConfig {
    @Bean
    public ObjectMapper jacksonObjectMapper(Jackson2ObjectMapperBuilder builder) {
        ObjectMapper objectMapper = builder.createXmlMapper(false).build();
        // 全局配置序列化返回 JSON 处理
        SimpleModule simpleModule = new SimpleModule();
        // 将使用String来序列化BigDecimal类型
        simpleModule.addSerializer(BigDecimal.class, ToStringSerializer.instance);
        objectMapper.registerModule(simpleModule);
        return objectMapper;
    }
}

import com.fasterxml.classmate.TypeResolver;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.util.ReflectionUtils;
import org.springframework.web.servlet.mvc.method.RequestMappingInfoHandlerMapping;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.oas.annotations.EnableOpenApi;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.service.Contact;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.spring.web.plugins.WebFluxRequestHandlerProvider;
import springfox.documentation.spring.web.plugins.WebMvcRequestHandlerProvider;
 
import java.lang.reflect.Field;
import java.math.BigDecimal;
import java.util.List;
import java.util.stream.Collectors;
 
@Configuration
@EnableOpenApi
public class SwaggerConfig {

    @Autowired
    private TypeResolver typeResolver;
    /**
     * 创建API应用
     * apiInfo() 增加API相关信息
     * 通过select()函数返回一个ApiSelectorBuilder实例,用来控制哪些接口暴露给Swagger来展现，
     * 本例采用指定扫描的包路径来定义指定要建立API的目录。
     *
     * @return
     */
 
 
    //再定义一个Docket
    @Bean
    public Docket desertsApi2() {
        return new Docket(DocumentationType.OAS_30)
                .apiInfo(apiInfo("Swagger3.0", "1.0"))
                .select()
                .apis(RequestHandlerSelectors.basePackage("com.xxx.controller"))
                .paths(PathSelectors.any())
                .build()
                .directModelSubstitute(BigDecimal.class, String.class)
                .additionalModels(typeResolver.resolve(XXX.class), typeResolver.resolve(XXXX.class)) //这里将'YourEntity'类加入swagger文档中，如果实体类没有在接口中作为入参，那么不会直接在Schemas中显示，所以这里可以手动列出一些Eentity类
                .groupName("xxxx")
                .enable(true);
    }
 
    /**
     * 创建该API的基本信息（这些基本信息会展现在文档页面中）
     * 访问地址：http://ip:port/swagger-ui.html
     *
     * @return
     */
    private ApiInfo apiInfo(String title, String version) {
        return new ApiInfoBuilder()
                .title(title)
                .description("api信息")
                .contact(new Contact("GMS", "", ""))
                .termsOfServiceUrl("")
                .version(version)
                .build();
    }
 
    @Bean
    public static BeanPostProcessor springfoxHandlerProviderBeanPostProcessor() {
        return new BeanPostProcessor() {
 
            @Override
            public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
                if (bean instanceof WebMvcRequestHandlerProvider || bean instanceof WebFluxRequestHandlerProvider) {
                    customizeSpringfoxHandlerMappings(getHandlerMappings(bean));
                }
                return bean;
            }
 
            private <T extends RequestMappingInfoHandlerMapping> void customizeSpringfoxHandlerMappings(List<T> mappings) {
                List<T> copy = mappings.stream()
                        .filter(mapping -> mapping.getPatternParser() == null)
                        .collect(Collectors.toList());
                mappings.clear();
                mappings.addAll(copy);
            }
 
            @SuppressWarnings("unchecked")
            private List<RequestMappingInfoHandlerMapping> getHandlerMappings(Object bean) {
                try {
                    Field field = ReflectionUtils.findField(bean.getClass(), "handlerMappings");
                    field.setAccessible(true);
                    return (List<RequestMappingInfoHandlerMapping>) field.get(bean);
                } catch (IllegalArgumentException | IllegalAccessException e) {
                    throw new IllegalStateException(e);
                }
            }
        };
    }
}

Mybatisplus 分页插件

import com.baomidou.mybatisplus.annotation.DbType;
import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import java.util.Collections;

@EnableTransactionManagement
@Configuration
@MapperScan("com.xxx.mapper")
public class MybatisPlusConfig {
    /**
     * 分页插件 3.5.X
     * @author zhengkai.blog.csdn.net
     */
    @Bean
    public PaginationInnerInterceptor paginationInnerInterceptor() {
        PaginationInnerInterceptor paginationInterceptor = new PaginationInnerInterceptor();
        // 设置最大单页限制数量，默认 500 条，-1 不受限制
        paginationInterceptor.setMaxLimit(-1L);
        paginationInterceptor.setDbType(DbType.ORACLE);
        // 开启 count 的 join 优化,只针对部分 left join
        paginationInterceptor.setOptimizeJoin(true);
        return paginationInterceptor;
    }
    @Bean
    public MybatisPlusInterceptor mybatisPlusInterceptor(){
        MybatisPlusInterceptor mybatisPlusInterceptor = new MybatisPlusInterceptor();
        mybatisPlusInterceptor.setInterceptors(Collections.singletonList(paginationInnerInterceptor()));
        return mybatisPlusInterceptor;
    }
}

    public ApiResult page(XXXDTO xxxDTO, int current, int size) {
        IPage<CBRMLyt> page = new Page<>(current,size);
        QueryWrapper<CBRMLyt> queryWrapper = new QueryWrapper<>();
        if (null != xxxDTO.getXXX() && xxxDTO.getXXX().length > 0) {
            queryWrapper.in("XX", Arrays.asList(xxxDTO.getXXX()));
        }
        queryWrapper.orderByAsc("XX1", "XX2");
        return ApiResult.ok(lytMapper.selectPage(page, queryWrapper));
    }