一、工具類(lèi)

package com.mdw.platform.orders.config;

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;

import java.io.IOException;
import java.math.BigDecimal;
import java.math.RoundingMode;
import java.text.DecimalFormat;


/**
 * 格式化
 *
 * double 精確到小數(shù)點(diǎn)后兩位
 * Date:     2019/10/15 11:58
 * title:title
 * @author ht
 */
public class CustomerDoubleSerialize extends JsonSerializer<Double> {

    /**
     * 原本這里是  ##.00 ,帶來(lái)的問(wèn)題是如果數(shù)據(jù)庫(kù)數(shù)據(jù)為0.00返回“ .00 “經(jīng)評(píng)論指正，改為0.00
     */
    private DecimalFormat df = new DecimalFormat("0.00");

    @Override
    public void serialize(Double arg0, JsonGenerator arg1, SerializerProvider arg2) throws IOException {
        if(arg0 != null) {
            BigDecimal bigDecimal = new BigDecimal(String.valueOf(arg0));
            df.setRoundingMode(RoundingMode.HALF_UP);
            //四舍五入。需要將數(shù)據(jù)轉(zhuǎn)成bigDecimal, 否則會(huì)存在經(jīng)度丟失問(wèn)題
            String format = df.format(bigDecimal);
            double aDouble = Double.parseDouble(format);
            arg1.writeNumber(aDouble);//返回?cái)?shù)字格式
        }
    }
}

二、 實(shí)現(xiàn)

對(duì)實(shí)體類(lèi)加上@JsonSerialize(using = CustomerDoubleSerialize.class)

   import com.fasterxml.jackson.databind.annotation.JsonSerialize;
  
    /**
     * 提貨費(fèi)用
     */
    @JsonSerialize(using = CustomerDoubleSerialize.class)
    private Double pickUpCost;