两个Long类型相乘溢出怎么解决

Question

如题，今天面试，面试官问到一个问题，怎么处理两个Long类型相乘溢出的问题？

Answer 1

[code="java"]
public static void main(String[] args) throws Exception {
long a = Long.MAX_VALUE;
long b = Long.MAX_VALUE;

    BigDecimal ba = new BigDecimal(String.valueOf(a));
    BigDecimal bb = new BigDecimal(String.valueOf(b));
    BigDecimal bc = ba.multiply(bb);
    System.out.println(String.valueOf(a));
    System.out.println(String.valueOf(b));
    System.out.println(bc);
}

[/code]

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9223372036854775807
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