Java 大数负数？

Question

我尝试从字符串中获取大数字，但二进制值是错误的。

        priKeyData = HexByteKit.Hex2Byte("b8dfc598d14c0bb032c1f4eb1fcdb033289002f38cc16b2120dfa697f8982bef");
        BigInteger priKeyBN2 = new BigInteger(priKeyData);
        String s3 = priKeyBN2.toString(2);

它给出:-1000111001000000011101001100111001011101011001111110100010011111100110100111110000010110001010011100000001100100100111111 001100110101110110111111111101000011000111001100111110100101001101111011011111001000000101100101101000000001110110011111010 10000010001

但正确的应该是:

10111000110111111100010110011000110100010100110000001011101100000011001011000001111101001110101100011111110011011011000 000110011001010001001000000000010111100111000110011000001011010110010000100100000110111111010011010010111111110001001100000 10101111101111

http://www.mobilefish.com/services/big_number/big_number.php

右边的是256位，所以在Java bignumber类中会溢出？那么如何在Java加密算法的某些步骤中使用这个256位数字呢？

谢谢。

Answer 1

我不知道 HexByteKit 是什么，但从十六进制字符串构造 BigInteger 给出了正确的结果:

BigInteger priKeyBN2 = new BigInteger("b8dfc598d14c0bb032c1f4eb1fcdb033289002f38cc16b2120dfa697f8982bef", 16);
String s3 = priKeyBN2.toString(2);