Given a hexstring this will return the byte array corresponding to string : Hex Oct « Data Type « Java Tutorial

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 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
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 * See the License for the specific language governing permissions and
 * limitations under the License.

import java.text.DateFormat;
import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.List;
import java.util.StringTokenizer;
import java.util.Collection;

 * General string utils
public class StringUtils {

  final public static char COMMA = ',';
  final public static String COMMA_STR = ",";
  final public static char ESCAPE_CHAR = '\\';
  private static DecimalFormat oneDecimal = new DecimalFormat("0.0");
   * Given a hexstring this will return the byte array corresponding to the
   * string
   * @param hex the hex String array
   * @return a byte array that is a hex string representation of the given
   *         string. The size of the byte array is therefore hex.length/2
  public static byte[] hexStringToByte(String hex) {
    byte[] bts = new byte[hex.length() / 2];
    for (int i = 0; i < bts.length; i++) {
      bts[i] = (byte) Integer.parseInt(hex.substring(2 * i, 2 * i + 2), 16);
    return bts;

2.9.Hex Oct
2.9.1.Hexadecimal integer literal
2.9.2.A hexadecimal literal of type long
2.9.3.Defining integer literals as octal values
2.9.4.Decode string to integer
2.9.5.Convert octal number to decimal number example
2.9.6.Convert decimal integer to octal number example
2.9.7.Convert decimal integer to hexadecimal number example
2.9.8.Parsing and Formatting a Number into Binary
2.9.9.Convert byte array to Hex String
2.9.10.Convert the bytes to a hex string representation of the bytes
2.9.11.Converting hexadecimal strings
2.9.12.Dumps data in hexadecimal format
2.9.13.Given a hexstring this will return the byte array corresponding to string
2.9.14.Hex encoder/decoder implementation borrowed from BouncyCastle
2.9.15.Returns the hexadecimal value of the supplied byte array
2.9.16.A custom number formatter that formats numbers as hexadecimal strings.
2.9.17.Decodes Hex data into octects
2.9.18.Decodes Base64 data into octects
2.9.19.Helper function that returns a char from an hex
2.9.20.Encodes hex octects into Base64
2.9.21.Hex encoder and decoder.
2.9.22.Helper function that dump an array of bytes in hex pair form, without '0x' and space chars
2.9.23.dump an array of bytes in hex form
2.9.24.Decode byte array