Java中钱应该使用什么数据类型

Joda Money

<dependency>
  <groupId>org.joda</groupId>
  <artifactId>joda-money</artifactId>
  <version>1.0.2</version>
</dependency>

 // create a monetary value
  Money money = Money.parse("USD 23.87");
  
  // add another amount with safe double conversion
  CurrencyUnit usd = CurrencyUnit.of("USD");
  money = money.plus(Money.of(usd, 12.43d));
  
  // subtracts an amount in dollars
  money = money.minusMajor(2);
  
  // multiplies by 3.5 with rounding
  money = money.multipliedBy(3.5d, RoundingMode.DOWN);
  
  // compare two amounts
  boolean bigAmount = money.isGreaterThan(dailyWage);
  
  // convert to GBP using a supplied rate
  BigDecimal conversionRate = ...;  // obtained from code outside Joda-Money
  Money moneyGBP = money.convertedTo(CurrencyUnit.GBP, conversionRate, RoundingMode.HALF_UP);
  
  // use a BigMoney for more complex calculations where scale matters
  BigMoney moneyCalc = money.toBigMoney();

javamoney

<dependency>
    <groupId>org.javamoney</groupId>
    <artifactId>moneta</artifactId>
    <version>1.0</version>
</dependency>

 package com.example.money;

import static org.junit.Assert.assertThat;
import static org.hamcrest.CoreMatchers.is;

import java.util.Locale;

import javax.money.Monetary;
import javax.money.MonetaryAmount;
import javax.money.MonetaryRounding;
import javax.money.format.MonetaryAmountFormat;
import javax.money.format.MonetaryFormats;

import org.junit.Test;

public class MoneyTest {

    @Test
    public void testMoneyApi() {
        MonetaryAmount eurAmount1 = Monetary.getDefaultAmountFactory().setNumber(1.1111).setCurrency("EUR").create();
        MonetaryAmount eurAmount2 = Monetary.getDefaultAmountFactory().setNumber(1.1141).setCurrency("EUR").create();

        MonetaryAmount eurAmount3 = eurAmount1.add(eurAmount2);
        assertThat(eurAmount3.toString(), is("EUR 2.2252"));

        MonetaryRounding defaultRounding = Monetary.getDefaultRounding();
        MonetaryAmount eurAmount4 = eurAmount3.with(defaultRounding);
        assertThat(eurAmount4.toString(), is("EUR 2.23"));

        MonetaryAmountFormat germanFormat = MonetaryFormats.getAmountFormat(Locale.GERMAN);
        assertThat(germanFormat.format(eurAmount4), is("EUR 2,23") );
    }