java - parseInt on a string of 8 bits returns a negative value when the first bit is 1 -


i've got huge string of bits (with \n in too) pass parameter method, should isolate bits 8 8, , convert them bytes using parseint().

thing is, every time substring of 8 bits starts 1, resulting byte negative number. example, first substring '10001101', , resulting byte -115. can't seem figure out why, can help? works fine other substrings.

here's code, if needed :

static string bitstobytes(string genestring) {     string genestring_temp = "", sub;      for(int = 0; < genestring.length(); = i+8) {         sub = genestring.substring(i, i+8);          if (sub.indexof("\n") != -1) {             if (sub.indexof("\n") != genestring.length())                 sub = sub.substring(0, sub.indexof("\n")) + sub.substring(sub.indexof("\n")+1, sub.length()) + genestring.charat(i+9);         }          byte octet = (byte) integer.parseint(sub, 2);          system.out.println(octet);          genestring_temp = genestring_temp + octet;     }      genestring = genestring_temp + "\n";      return genestring; }

in java, byte signed type, meaning when significant bit set 1, number interpreted negative.

this precisely happens when print byte here:

system.out.println(octet);

since printstream not have overload of println takes single byte, overload takes int gets called. since octet's significant bit set 1, number gets sign-extended replicating sign bit bits 9..32, resulting in printout of negative number.


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