BigDecimal 0 不等于 0.00 equals问题

文章目录

• BigDecimal 0 不等于 0.00 equals问题

• 问题场景
• 解决办法
• 复现和修复的代码

BigDecimal 0 不等于 0.00 equals问题

问题场景

在执行某退款时，需要检验一下公式是否相等，避免在数据异常时执行了退款，但出现了一个问题，左边为0，右边计算后为0.00，使用BigDecimal 的equals方法去判定BigDecimal的0 和BigDecimal的0.00返回不相等！

天猫前置抵扣退款结算时：质检价0 ！= 前置抵扣已使用金额0+本次结算前线下结算额-9200.00+本次退款金额9200.00

BigDecimal 的equals方法源码如下，在精度不一致的时候会提前返回不相等~

/**
     * Compares this {@code BigDecimal} with the specified
     * {@code Object} for equality.  Unlike {@link
     * #compareTo(BigDecimal) compareTo}, this method considers two
     * {@code BigDecimal} objects equal only if they are equal in
     * value and scale (thus 2.0 is not equal to 2.00 when compared by
     * this method).
     *
     * @param  x {@code Object} to which this {@code BigDecimal} is
     *         to be compared.
     * @return {@code true} if and only if the specified {@code Object} is a
     *         {@code BigDecimal} whose value and scale are equal to this
     *         {@code BigDecimal}'s.
     * @see    #compareTo(java.math.BigDecimal)
     * @see    #hashCode
     */
    @Override
    public boolean equals(Object x) {
        if (!(x instanceof BigDecimal))
            return false;
        BigDecimal xDec = (BigDecimal) x;
        if (x == this)
            return true;
        if (scale != xDec.scale)
            return false;
        long s = this.intCompact;
        long xs = xDec.intCompact;
        if (s != INFLATED) {
            if (xs == INFLATED)
                xs = compactValFor(xDec.intVal);
            return xs == s;
        } else if (xs != INFLATED)
            return xs == compactValFor(this.intVal);

        return this.inflated().equals(xDec.inflated());
    }

解决办法

请使用compareTo == 0来判断

复现和修复的代码