springboot项目配置参数请求及返回均为下划线方式

1.请求参数为下划线
下划线方式参数请求，使用对象接收，则需要进行下划线转驼峰处理：
注意：请求接口不可使用@ModelAttribute接收对象，其原理和@RequestParam(“userId”)相同，请求参数根据后台所定义的接收参数名一致，不会进行驼峰转换处理。
1.自定义参数转换类，重写ServletRequestDataBinder中addBindValues方法，对参数进行处理

import org.springframework.beans.MutablePropertyValues;
import org.springframework.beans.PropertyValue;
import org.springframework.web.bind.ServletRequestDataBinder;
import javax.servlet.ServletRequest;
import java.util.LinkedList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**

• 自定义CustomServletRequestDataBinder类,继承ServletRequestDataBinder,
• 重写addBindValues方法,将入参通过underLineToCamel方法进行转换处理
  *
• @author Tom
• @date 2021-07-23
  */
  public class CustomServletRequestDataBinder extends ServletRequestDataBinder { private final Pattern underLinePattern = Pattern.compile(“_(\w)”); public CustomServletRequestDataBinder(final Object target) {
  super(target);
  } /**
  • 遍历请求参数对象 把请求参数的名转换成驼峰体,重写addBindValues绑定数值的方法
  • @param mpvs 请求参数列表
  • @param request 请求
    */
    @Override
    protected void addBindValues(MutablePropertyValues mpvs, ServletRequest request) {
    List pvs = mpvs.getPropertyValueList();
    List adds = new LinkedList<>();
    for (PropertyValue pv : pvs) {
    String name = pv.getName();
    String camel = this.underLineToCamel(name);
    if (!name.equals(camel)) {
    adds.add(new PropertyValue(camel, pv.getValue()));
    }
    }
    pvs.addAll(adds);
    }

  /**

  • 下划线转驼峰方法(如: 把app_id转换成appId)
  • @param value 要转换的下划线字符串
  • @return 驼峰体字符串
    */
    private String underLineToCamel(final String value) {
    final StringBuffer sb = new StringBuffer();
    Matcher m = this.underLinePattern.matcher(value);
    while (m.find()){
    m.appendReplacement(sb, m.group(1).toUpperCase());
    }
    m.appendTail(sb);
    return sb.toString();
    }

}

2.自定义属性处理器CustomServletModelAttributeMethodProcessor，继承ServletModelAttributeMethodProcessor重写bindRequestParameters方法，将bind方法替换为我们自定义的CustomServletRequestDataBinder

import org.springframework.util.Assert;
import org.springframework.web.bind.ServletRequestDataBinder;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.servlet.mvc.method.annotation.ServletModelAttributeMethodProcessor;
import javax.servlet.ServletRequest;

/**

• 自定义属性处理器: CustomServletModelAttributeMethodProcessor
• 继承ServletModelAttributeMethodProcessor类,重写bindRequestParameters方法,
• 将bind方法替换为我们自定义的CustomServletRequestDataBinder
  *
• @author Tom
• @date 2021-07-23
  */
  public class CustomServletModelAttributeMethodProcessor extends ServletModelAttributeMethodProcessor { public CustomServletModelAttributeMethodProcessor(final boolean annotationNotRequired) {
  super(annotationNotRequired);
  } @Override
  protected void bindRequestParameters(WebDataBinder binder, NativeWebRequest request) {
  ServletRequest servletRequest = request.getNativeRequest(ServletRequest.class);
  Assert.state(servletRequest != null, “No ServletRequest”);
  ServletRequestDataBinder servletBinder = (ServletRequestDataBinder) binder;
  /**
  * ServletModelAttributeMethodProcessor此处使用的servletBinder.bind(servletRequest)
  * 修改的目的是为了将ServletRequestDataBinder换成自定的CustomServletRequestDataBinder
  */
  new CustomServletRequestDataBinder(servletBinder.getTarget()).bind(servletRequest);
  }

}

3.实现WebMvcConfigurer类，重写addArgumentResolvers方法，引入CustomServletModelAttributeMethodProcessor

import com.alibaba.fastjson.serializer.SerializerFeature;
import com.alibaba.fastjson.support.config.FastJsonConfig;
import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter;
import com.xiaomi.config.request.CustomServletModelAttributeMethodProcessor;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import java.util.ArrayList;
import java.util.List;

/**

• 添加自定义拦截器,消息转换器等
  *
• @Author Tom
• @Date 2021-07-22
• @Description 实现WebMvcConfigurer接口
  */
  @Configuration
  public class WebConfig implements WebMvcConfigurer { /**
  • 配置入参转换器 – 重写HTTP请求参数转换规则(前端请求参数为下划线类型,自动转换为驼峰形式进行对象参数封装)
  • @param resolvers
    */
    @Override
    public void addArgumentResolvers(List resolvers) {
    resolvers.add(new CustomServletModelAttributeMethodProcessor(true));
    }
    }

    2.返回参数将驼峰转换为下划线
    使用Jackson方式处理：
    方式一：

import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.PropertyNamingStrategy;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.module.SimpleModule;
import com.fasterxml.jackson.databind.ser.std.ToStringSerializer;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalDateDeserializer;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalDateTimeDeserializer;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalTimeDeserializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateSerializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateTimeSerializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalTimeSerializer;
import org.springframework.boot.autoconfigure.AutoConfigureBefore;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.jackson.JacksonAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import java.math.BigDecimal;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.format.DateTimeFormatter;

/**

• 解决前端和后台交互过程中时间格式问题,比如LocalDateTime中带”T的问题”
  *
• @author Tom
• @date 2021-07-22
  */
  @Configuration
  @ConditionalOnClass({ObjectMapper.class})
  @AutoConfigureBefore({JacksonAutoConfiguration.class})
  public class JacksonConfig { public JacksonConfig() {
  } @Bean
  public ObjectMapper getObjectMapper() {
  ObjectMapper objectMapper = new ObjectMapper();
  JavaTimeModule javaTimeModule = new JavaTimeModule();
  javaTimeModule.addSerializer(LocalDateTime.class, new LocalDateTimeSerializer(DateTimeFormatter.ofPattern(“yyyy-MM-dd HH:mm:ss”)));
  javaTimeModule.addSerializer(LocalDate.class, new LocalDateSerializer(DateTimeFormatter.ofPattern(“yyyy-MM-dd”)));
  javaTimeModule.addSerializer(LocalTime.class, new LocalTimeSerializer(DateTimeFormatter.ofPattern(“HH:mm:ss”)));
  javaTimeModule.addDeserializer(LocalDateTime.class, new LocalDateTimeDeserializer(DateTimeFormatter.ofPattern(“yyyy-MM-dd HH:mm:ss”)));
  javaTimeModule.addDeserializer(LocalDate.class, new LocalDateDeserializer(DateTimeFormatter.ofPattern(“yyyy-MM-dd”)));
  javaTimeModule.addDeserializer(LocalTime.class, new LocalTimeDeserializer(DateTimeFormatter.ofPattern(“HH:mm:ss”)));
  objectMapper.registerModule(javaTimeModule);
  SimpleModule simpleModule = new SimpleModule();
  simpleModule.addSerializer(Long.class, ToStringSerializer.instance);
  simpleModule.addSerializer(Long.TYPE, ToStringSerializer.instance);
  simpleModule.addSerializer(Long.TYPE, ToStringSerializer.instance);
  simpleModule.addSerializer(BigDecimal.class, ToStringSerializer.instance);
  objectMapper.registerModule(simpleModule);
  objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
  objectMapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
  objectMapper.setPropertyNamingStrategy(PropertyNamingStrategy.SNAKE_CASE);//对于fastjson缺省使用SnakeCase策略(统一对象参数下划线形式)
  objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
  return objectMapper;
  }
  }

上面代码中，为我本地配置的JacksonConfig，其中将对象参数驼峰形式转换为下划线的代码仅一句：
PS：由于Jackson本身已经封装好，所以需要情况下直接配置即可

objectMapper.setPropertyNamingStrategy(PropertyNamingStrategy.SNAKE_CASE);//对于fastjson缺省使用SnakeCase策略(统一对象参数下划线形式)

方式二：
在配置文件中修改：

spring:
application:
name:
jackson:
date-format: yyyy-MM-dd HH:mm:ss
time-zone: GMT+8
default-property-inclusion: non_null
property-naming-strategy: SNAKE_CASE #对于fastjson缺省使用SnakeCase策略(统一对象参数下划线形式)

property-naming-strategy: SNAKE_CASE
fastjson缺省使用四种策略：

属性名策略说明：

CamelCase策略，Java对象属性：personId，序列化后属性：persionId

PascalCase策略，Java对象属性：personId，序列化后属性：PersonId

SnakeCase策略，Java对象属性：personId，序列化后属性：person_id

KebabCase策略，Java对象属性：personId，序列化后属性：person-id