I'm working on Huffman compression.
String binaryString = "01011110";
outFile.write(byte);
I have a String which I want to convert to a byte so that I can write that byte to the file. Does anyone know how I can do this?
3 Answers
You can turn that String into a numerical value using the overloaded parseByte that lets you specify the radix:
String binaryString = "01011110";
byte b = Byte.parseByte(binaryString, 2); //this parses the string as a binary number
outFile.write(b);
The second argument to parseByte() lets you specify the Number system in which the String should be parsed. By default, a radix of 10 is used because us humans usually use the decimal system. The 2 says that the number should be treated as a binary value (which is base 2).
5 Comments
Kristina
Thank you! What does
2 mean on the second line?
f1sh
It lets you specify the numerical system in which the String should be parsed. By default, a radix of 10 is used because us humans usually use the decimal system. The 2 says that the number should be treated as a binary value (which is base 2).
Kristina
Ahh, okay! When my program comes to the next binaryString, I get this exception
NumberFormatException: Value out of range. Value:"10000011" Radix:2. What is wrong?
tgdavies
Byte can only represent numbers from -128 to 127, and 10000011 is 131.
tgdavies
You can use
byte i = (byte)(Integer.parseInt("10000011", 2) & 0xff)You can use Byte.parseByte() with a radix of 2:
byte b = Byte.parseByte(str, 2);
example:
System.out.println(Byte.parseByte("01100110", 2));
Comments
Could write (a String[256] with each manually written 1 and 0 set of 8 bits) it out , its only 256 of them. gives you the ability to check with String.indexOf(binnum[arrayIndex]) and make a corresponding array of new byte[256] and set each in matching order with new Integer(increment).byteValue(), it should reproduce for checking printable over the byte[] array using new Byte(bytarray[incr]).intValue()+"\n"
"01011110"or do you have a string"^"?String binaryString = "01011110";.Sorry about that.Byte.parseByte("01011110", 2)