aQute.lib.hex.Hex Maven / Gradle / Ivy
package aQute.lib.hex;
import java.io.IOException;
import java.util.Objects;
import java.util.regex.Pattern;
/*
* Hex converter.
*
* TODO Implement string to byte[]
*/
public class Hex {
static Pattern HEX_P = Pattern.compile("(?:[0-9a-fA-F][0-9a-fA-Z])+");
final static char[] HEX = {
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
};
public final static byte[] toByteArray(String string) {
Objects.requireNonNull(string, "The hex string must not be null.");
string = string.trim();
if ((string.length() & 1) != 0)
throw new IllegalArgumentException("a hex string must have an even length");
byte[] out = new byte[string.length() / 2];
for (int i = 0; i < out.length; i++) {
int high = nibble(string.charAt(i * 2)) << 4;
int low = nibble(string.charAt(i * 2 + 1));
out[i] = (byte) (high + low);
}
return out;
}
public static String toHex(byte b) {
char low = HEX[b & 0xF];
char high = HEX[(b & 0xF0) >> 4];
return new String(new char[] {
high, low
});
}
public final static int nibble(char c) {
if (c >= '0' && c <= '9')
return c - '0';
if (c >= 'A' && c <= 'F')
return c - 'A' + 10;
if (c >= 'a' && c <= 'f')
return c - 'a' + 10;
throw new IllegalArgumentException("Not a hex digit: " + c);
}
public final static String toHexString(byte data[]) {
StringBuilder sb = new StringBuilder();
try {
append(sb, data);
} catch (IOException e) {
// cannot happen with sb
}
return sb.toString();
}
public final static void append(Appendable sb, byte[] data) throws IOException {
for (int i = 0; i < data.length; i++) {
sb.append(nibble(data[i] >> 4));
sb.append(nibble(data[i]));
}
}
public final static char nibble(int i) {
return HEX[i & 0xF];
}
public static boolean isHex(String pub) {
return HEX_P.matcher(pub)
.matches();
}
public static boolean isHexCharacter(char c) {
if (c < '0')
return false;
if (c <= '9')
return true;
if (c < 'A')
return false;
if (c <= 'F')
return true;
// lower case are higher than upper case in Unicode!
if (c < 'a')
return false;
return c <= 'f';
}
public static String separated(byte[] bytes, String separator) {
String del="";
StringBuilder sb = new StringBuilder();
for ( byte x : bytes) {
sb.append(del);
sb.append(toHex(x));
del = separator;
}
return sb.toString();
}
}