Java Utililty Methods Base Convert

List of utility methods to do Base Convert

  1. HOME
  2. Java
  3. B
  4. Base Convert

Description

The list of methods to do Base Convert are organized into topic(s).

Method

longfromBase(String num, String baseChars)
Decode number from any base. 
int base = baseChars.length();
long x = 0;
if (num != null)
    for (int i = 0; i < num.length(); i++) {
        char c = num.charAt(i);
        int p = baseChars.indexOf(c);
        if (p < 0)
            throw new RuntimeException("fromBase() Invalid character '" + c + "' at position " + i);
...
StringfromBase10(final long base10)
from Base 
if (base10 == 0) {
    return "0";
long temp = base10;
final StringBuilder sb = new StringBuilder();
while (temp > 0) {
    temp = fromBase10(temp, sb);
return sb.reverse().toString();
byte[]fromBase16(String data)
from Base 
boolean extraByte = data.length() % 2 == 1;
byte[] result = new byte[data.length() / 2 + (extraByte ? 1 : 0)];
for (int i = 0; i < result.length; i++) {
    int value = Integer.parseInt(data.substring(2 * i, Math.min(2 * i + 2, data.length())), 16);
    result[i] = (byte) (value & 0xff);
return result;
byte[]fromBase16toByteArray(String bytes)
This method return a byte[] from a String. 
int[] values = fromBase16toIntArray(bytes);
byte[] returns = new byte[values.length];
for (int i = 0; i < values.length; i++) {
    returns[i] = (byte) (values[i] & 0xFF);
return returns;
int[]fromBase16toIntArray(String bytes)
from Baseto Int Array 
final String PATTERN = "\\s*((0x[0-9a-f]{2}|[0-9a-f]{2})\\s*)+";
bytes = bytes.toLowerCase();
if (!bytes.matches(PATTERN)) {
    throw new IllegalArgumentException("Unable to parse " + bytes + " doesn't match regex " + PATTERN);
String[] singleBytes = bytes.split("\\s+");
String item;
int[] values = new int[singleBytes.length];
...
intfromBase26(String number)
Convert a base-26 representation into a number, considering it to represent a value in base-26 using the characters a-z or A-Z - the string is treated case-insensitively. 
if (!number.matches("^[a-zA-Z]*$"))
    throw new NumberFormatException("Non-alphabetic characters in string.");
int s = 0;
if (number != null && number.length() > 0) {
    number = number.toLowerCase();
    s = (number.charAt(0) - 'a');
    for (int i = 1; i < number.length(); i++) {
        s *= 26;
...
intfromBase36(String base36)

Takes a Base 36 String and returns the Base 10 Integer equivalent

return Integer.parseInt(base36, 36);
intfromBase36(String base36Number)
from Base 
return fromOtherBaseToDecimal(36, base36Number);
byte[]fromBase58(String input)
from Base 
if (input.length() == 0) {
    return new byte[0];
byte[] input58 = new byte[input.length()];
for (int i = 0; i < input.length(); ++i) {
    char c = input.charAt(i);
    int digit58 = -1;
    if (c >= 0 && c < 128) {
...
intfromBase62(String base62Number)
from Base 
return fromOtherBaseToDecimal(62, base62Number);