BigDecimal如何比较大小

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BigDecimal比较大小
   这个类是java里精确计算的类,下面说一下两个BigDecimal对象大小,相等的判断
   1 比较对象是否相等
     一般的对象用equals,但是BigDecimal比较特殊,举个例子:
     BigDecimal a=BigDecimal.valueOf(1.0);
     BigDecimal b=BigDecimal.valueOf(1.000);

     在现实中这两个数字是相等的,但是如果用
     a.equals(b)结果是false;怎么不相等了呢?因为equals是比较内容,“1.0”和“1.000”当然不一样了

     解决办法:
            if(a.compareTo(b)==0) 结果是true

     public int compareTo(BigDecimal val)
          Compares this BigDecimal with the specified BigDecimal.
         Two BigDecimal objects that are equal in value but have a different
         scale (like 2.0 and 2.00) are considered equal by this method.
         This method is provided in preference to individual methods for each of
         the six boolean comparison operators (<, ==, >, >=, !=, <=).
         The suggested idiom for performing these comparisons is: (x.compareTo(y) <op> 0), where <op> is one of the six comparison operators.

    Specified by:
    compareTo in interface Comparable<BigDecimal>
    Parameters:
    val - BigDecimal to which this BigDecimal is to be compared.
    Returns:
       -1, 0, or 1 as this BigDecimal is numerically less than, equal to, or greater than val.

    简单翻译:
           结果是
-1 小于 
0 等于
1 大于