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gurux.common.android package implements interfaces that are needed for Gurux Media components and Gurux Device Framework. Purpose of Gurux Device Framework is help you to read your devices, meters and sensors easier
//
// --------------------------------------------------------------------------
// Gurux Ltd
//
//
//
// Filename: $HeadURL$
//
// Version: $Revision$,
// $Date$
// $Author$
//
// Copyright (c) Gurux Ltd
//
//---------------------------------------------------------------------------
//
// DESCRIPTION
//
// This file is a part of Gurux Device Framework.
//
// Gurux Device Framework is Open Source software; you can redistribute it
// and/or modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; version 2 of the License.
// Gurux Device Framework is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
// See the GNU General Public License for more details.
//
// More information of Gurux products: http://www.gurux.org
//
// This code is licensed under the GNU General Public License v2.
// Full text may be retrieved at http://www.gnu.org/licenses/gpl-2.0.txt
//---------------------------------------------------------------------------
package gurux.common;
import java.io.UnsupportedEncodingException;
/**
* Common methods for device communicating.
*
* @author Gurux Ltd.
*/
public final class GXCommon {
/**
* This is utility class and user can't create it.
*/
private GXCommon() {
}
/**
* Amount of chars one byte is taken in string.
*/
static final int HEX_SIZE = 3;
/**
* Value of Hex A in decimal.
*/
static final int HEX_A_DECIMAL_VALUE = 10;
/**
* Maximum size of byte.
*/
static final int MAX_BYTE_SIZE = 0xFF;
/**
* Amount of bytes in short.
*/
static final int SHORT_BYTES = 2;
/**
* Amount of bytes in integer.
*/
static final int INTEGER_BYTES = 4;
/**
* Amount of bytes in long.
*/
static final int LONG_BYTES = 4;
/**
* Low part of the byte.
*/
static final int LOW_BYTE_PART = 0x0F;
/**
* Half a byte.
*/
static final int NIBBLE = 4;
/**
* Returns high part or the byte.
*
* @param value Byte value.
* @return High part of the byte.
*/
public static byte getHighByte(final int value) {
return (byte) (value >>> NIBBLE);
}
/**
* Get low part of the byte.
*
* @param value Byte value.
* @return Low part of the byte.
*/
public static byte getLowByte(final int value) {
return (byte) (value & LOW_BYTE_PART);
}
/**
* Convert byte array to Hex string.
*
* @param bytes Bytes to convert.
* @return Hex string.
*/
public static String bytesToHex(final byte[] bytes) {
// Return empty string if array is empty.
if (bytes == null || bytes.length == 0) {
return "";
}
final char[] hexArray = {'0', '1', '2', '3', '4', '5', '6', '7', '8',
'9', 'A', 'B', 'C', 'D', 'E', 'F'};
char[] hexChars = new char[bytes.length * HEX_SIZE];
int tmp;
for (int pos = 0; pos != bytes.length; ++pos) {
tmp = bytes[pos] & MAX_BYTE_SIZE;
hexChars[pos * HEX_SIZE] = hexArray[getHighByte(tmp)];
hexChars[pos * HEX_SIZE + 1] = hexArray[getLowByte(tmp)];
hexChars[pos * HEX_SIZE + 2] = ' ';
}
return new String(hexChars, 0, hexChars.length - 1);
}
/**
* Convert char hex value to byte value.
*
* @param c Character to convert hex.
* @return Byte value of hex char value.
*/
private static byte getValue(final byte c) {
byte value;
// Id char.
if (c > '9') {
if (c > 'Z') {
value = (byte) (c - 'a');
} else {
value = (byte) (c - 'A');
}
value += HEX_A_DECIMAL_VALUE;
} else {
// If number.
value = (byte) (c - '0');
}
return value;
}
/**
* Convert string to byte array.
*
* @param value Hex string.
* @return byte array.
*/
public static byte[] hexToBytes(final String value) {
byte[] buffer = new byte[value.length() / 2];
int lastValue = -1;
int index = 0;
try {
for (byte ch : value.getBytes("ASCII")) {
if (ch >= '0' && ch < 'g') {
if (lastValue == -1) {
lastValue = getValue(ch);
} else if (lastValue != -1) {
buffer[index] =
(byte) (lastValue << NIBBLE | getValue(ch));
lastValue = -1;
++index;
}
} else if (lastValue != -1) {
buffer[index] = getValue(ch);
lastValue = -1;
++index;
}
}
} catch (UnsupportedEncodingException e) {
throw new RuntimeException(e.getMessage());
}
byte[] tmp = new byte[index];
System.arraycopy(buffer, 0, tmp, 0, index);
return tmp;
}
}