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/**
* @author ETSI / STF462
* @version $URL$
* $Id$
*/
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
public class ByteHelper {
public static byte[] changeEndianness(byte [] in) {
byte[] out = new byte[in.length];
for(int i=0; i < in.length; i++) {
out[in.length - i -1] = in[i];
}
return out;
}
public static byte[] intToByteArray(int value, int length, ByteOrder byteOrder) {
if(byteOrder == ByteOrder.LITTLE_ENDIAN) {
return changeEndianness(intToByteArray(value, length));
}
return intToByteArray(value, length);
}
public static byte[] intToByteArray(int value, int length) {
byte[] b = new byte[length];
for (int i = length - 1; i >= 0; i--) {
int offset = (b.length - 1 - i) * 8;
b[i] = (byte) ((value >>> offset) & 0xFF);
}
return b;
}
public static byte[] floatToByteArray(final float value) {
return ByteBuffer.allocate(Float.SIZE / Byte.SIZE).putFloat(value).array();
}
public static byte[] longToByteArray(long value, int length, ByteOrder byteOrder) {
if(byteOrder == ByteOrder.LITTLE_ENDIAN) {
return changeEndianness(longToByteArray(value, length));
}
return longToByteArray(value, length);
}
public static byte[] longToByteArray(long value, int length) {
byte[] b = new byte[length];
for (int i = length - 1; i >= 0; i--) {
int offset = (b.length - 1 - i) * 8;
b[i] = (byte) ((value >>> offset) & 0xFF);
}
return b;
}
/** Convert a byte array into a boolean
*
* @param b The byte array to convert
* @return The boolean value on success, false otherwise
*/
public static Boolean byteArrayToBoolean(byte[] b) {
// Sanity check
if ((b == null) || (b.length != 1)) {
return null;
}
return new Boolean(b[0] == 0x01);
} // End of method byteArrayToBoolean
public static Short byteArrayToShort(final byte[] b, ByteOrder byteOrder) {
if(byteOrder == ByteOrder.LITTLE_ENDIAN) {
return byteArrayToShort(changeEndianness(b));
}
return byteArrayToShort(b);
}
/** Convert a byte array into a short value assuming that the first byte is the most significant
*
* @param b The byte array to convert
* @return The short value on success, 'Integer.MAX_VALUE' otherwise
*/
public static Short byteArrayToShort(final byte[] b) {
// Sanity check
if ((b == null) || ((b.length * Byte.SIZE) > Short.SIZE)) {
return Short.MAX_VALUE;
}
short value = 0;
for (Short i = 0; i < b.length; i++) {
value = (short)((value << 8) + (b[i] & 0xff));
}
return new Short(value);
} // End of method byteArrayToInt
public static Integer byteArrayToInt(final byte[] b, ByteOrder byteOrder) {
if(byteOrder == ByteOrder.LITTLE_ENDIAN) {
return byteArrayToInt(changeEndianness(b));
}
return byteArrayToInt(b);
}
/** Convert a byte array into an integer assuming that the first byte is the most significant
*
* @param b The byte array to convert
* @return The integer value on success, 'Integer.MAX_VALUE' otherwise
*/
public static Integer byteArrayToInt(final byte[] b) {
// Sanity check
if ((b == null) || ((b.length * Byte.SIZE) > Integer.SIZE)) {
return Integer.MAX_VALUE;
}
int value = 0;
for (int i = 0; i < b.length; i++) {
value = (value << 8) + (b[i] & 0xff);
}
return new Integer(value);
} // End of method byteArrayToInt
/** Convert a byte array into a signed integer assuming that padding bits are in first byte
*
* @param b The byte array to convert
* @param significantBits number of significant bits in the array
* @return The integer value
*/
public static int byteArrayToSignedInt(final byte[] b, final int significantBits) {
int value = 0;
for (int i = 0; i < b.length; i++) {
value = (value << 8) + (b[i] & 0xff);
}
int shift = 32 - significantBits;
// Restore sign bit by shifting left and right
if(shift > 0) {
value <<= shift;
value >>= shift;
}
return new Integer(value);
}
public static Long byteArrayToLong(final byte[] b, ByteOrder byteOrder) {
if(byteOrder == ByteOrder.LITTLE_ENDIAN) {
return byteArrayToLong(changeEndianness(b));
}
return byteArrayToLong(b);
}
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/** Convert a byte array into a Long assuming that the first byte is the most significant
*
* @param b The byte array to convert
* @return The Long value on success, 'Long.MAX_VALUE' otherwise
*/
public static Long byteArrayToLong(final byte[] b) {
// Sanity check
if ((b == null) || ((b.length * Byte.SIZE) > Long.SIZE)) {
return Long.MAX_VALUE;
}
long value = 0;
for (int i = 0; i < b.length; i++) {
value = (value << 8) + (b[i] & 0xff);
}
return new Long(value);
} // End of method byteArrayToLong
public static Float byteArrayToFloat(final byte[] b) {
return ByteBuffer.wrap(b).getFloat();
}
public static byte[] hexStringToByteArray(final String s) {
String str = "";
for(String ss : s.split("[^0-9A-Fa-f]")) {
str = str + ss;
}
int len = str.length();
byte[] data = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
data[i / 2] = (byte) ((Character.digit(str.charAt(i), 16) << 4)
+ Character.digit(str.charAt(i+1), 16));
}
return data;
}
public static byte[] concat(byte[]... arrays) {
int length = 0;
for (byte[] array : arrays) {
if(array != null) {
length += array.length;
}
}
byte[] result = new byte[length];
int position = 0;
for (byte[] array : arrays) {
if(array != null) {
System.arraycopy(array, 0, result, position, array.length);
position += array.length;
}
}
return result;
}
/** Extract a sub part of a byte array
* @param array The original array
* @param offset The offset to start the extract operation
* @param length The number of bytes to extract
* @return The sub part of a provided byte array
*/
public static byte[] extract(final byte[] array, final int offset, final int length) {
// Sanity check
if ((array == null) || (array.length == 0) || (offset > array.length)) {
return null;
}
byte[] result = new byte[length];
System.arraycopy(array, offset, result, 0, length);
return result;
}
/**
* This method convert a byte array containing the couple (length + string) into a string
* @param b The byte array to convert
* @return A string value
*/
public static String byteArrayWithLengthToString(final byte[] b) {
// Sanity check
if (b == null) {
return null;
} else if (b.length == 0) {
return "";
}
// Extract the length of the string
int length = byteArrayToInt(extract(b, 0, 4));
// Extract the the string
String result = "";
for (int i = 0; i < length; i++) {
result += (char)(b[4 + i]);
} // End of 'for' statement
}
public static String byteArrayToString(final byte[] buffer) {
String result = "";
if (buffer != null) {
for(int i=0; i < buffer.length; ++i) {
result += String.format("%02X", (byte)buffer[i]);
}
}
return result;
}
/**
* Dump a byte array in hex/ascii mode.
* @param label The dump label
* @param buffer The byte array to dump
*/
public synchronized static void dump(final String label, final byte[] buffer)
{
if ((buffer != null) && (buffer.length != 0))
{
System.out.println(label);
StringBuilder finalHexLine = new StringBuilder();
StringBuilder finalCharLine = new StringBuilder();
int nCounter = 0;
int nOffset = 0;
// Flush header.
System.out.println(" HEX | 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F : 0 1 2 3 4 5 6 7 8 9 A B C D E F ");
System.out.println("-----|+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+-:--+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+");
for (int i = 0; i < buffer.length; ++i)
{
byte c = (byte)buffer[i];
String fmtHex = String.format("%02x ", c);
String fmtChar = String.format("%c ", Character.isISOControl((char)c) || c < 0 ? '.' : (char)c);
if (nOffset % 16 == 0)
{
finalHexLine.append((String)String.format("%05x| ", nOffset));
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}
finalHexLine.append(fmtHex);
finalCharLine.append(fmtChar);
if (nCounter == 15)
{
// Flush line.
System.out.println(String.format("%s : %s", finalHexLine.toString(), finalCharLine.toString()));
// Reset buffer.
finalHexLine.delete(0, finalHexLine.length());
finalCharLine.delete(0, finalCharLine.length());
nCounter = 0;
}
else
{
nCounter++;
}
nOffset++;
}
if (nCounter < 16)
{
// Pad till 15.
for (int i = nCounter; i < 16; i++)
{
finalHexLine.append(" ");
finalCharLine.append(" ");
}
// Flush line.
System.out.println(String.format("%s : %s", finalHexLine.toString(), finalCharLine.toString()));
}
}
}
}