Java Hex to Byte Array convertHexStringToByteArray(String str, int numBytes, int numCharsPerByte)

Description

Convert raw memory data to byte array

License

Open Source License

Parameter

Parameter	Description
str	a parameter
numBytes	a parameter
numCharsPerByte	- number of characters per byte of data

Exception

Parameter	Description
NumberFormatException	an exception

Return

an array of byte, converted from a hex string

Declaration

public static byte[] convertHexStringToByteArray(String str, int numBytes, int numCharsPerByte)
        throws NumberFormatException 

Method Source Code

//package com.java2s;
/*******************************************************************************
 * Copyright (c) 2004, 2015 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:/*from  www  . j a va2 s. c o m*/
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

public class Main {
    /**
     * Convert raw memory data to byte array
     * @param str
     * @param numBytes
     * @param numCharsPerByte - number of characters per byte of data
     * @return an array of byte, converted from a hex string
     * @throws NumberFormatException
     */
    public static byte[] convertHexStringToByteArray(String str, int numBytes, int numCharsPerByte)
            throws NumberFormatException {
        if (str.length() == 0)
            return null;

        StringBuffer buf = new StringBuffer(str);

        // pad string with zeros
        int requiredPadding = numBytes * numCharsPerByte - str.length();
        while (requiredPadding > 0) {
            buf.insert(0, "0"); //$NON-NLS-1$
            requiredPadding--;
        }

        byte[] bytes = new byte[numBytes];
        str = buf.toString();

        // set data in memory
        for (int i = 0; i < bytes.length; i++) {
            // convert string to byte
            String oneByte = str.substring(i * 2, i * 2 + 2);

            Integer number = Integer.valueOf(oneByte, 16);
            if (number.compareTo(Integer.valueOf(Byte.toString(Byte.MAX_VALUE))) > 0) {
                int temp = number.intValue();
                temp = temp - 256;

                String tempStr = Integer.toString(temp);

                Byte myByte = Byte.valueOf(tempStr);
                bytes[i] = myByte.byteValue();
            } else {
                Byte myByte = Byte.valueOf(oneByte, 16);
                bytes[i] = myByte.byteValue();
            }
        }

        return bytes;
    }
}

Related

1. convertHexAsciiToByteArray(byte[] bytes)
2. convertHEXString2ByteArray(String value)
3. convertHexStringToByteArray(String hexString)
4. convertHexStringToByteArray(String s)
5. convertHexStringToByteNoSpace(String s)
6. convertHexStringToBytes(String hex)
7. convertHexStringToBytes(String hex)
8. convertHexToByteArray(String hexString)