SCViewer/com.minres.scviewer.ui/src/com/minres/scviewer/ui/Hex.java

36 lines
1.3 KiB
Java

package com.minres.scviewer.ui;
public final class Hex {
public static byte[] decode(final String hex) {
if (hex.length() % 2 != 0) {
throw new IllegalArgumentException("A hex string must contain an even number of characters: " + hex);
}
byte[] out = new byte[hex.length() / 2];
for (int i = 0; i < hex.length(); i += 2) {
int high = Character.digit(hex.charAt(i), 16);
int low = Character.digit(hex.charAt(i + 1), 16);
if (high == -1 || low == -1) {
throw new IllegalArgumentException("A hex string can only contain the characters 0-9, A-F, a-f: " + hex);
}
out[i / 2] = (byte) (high * 16 + low);
}
return out;
}
private static final char[] UPPER_HEX_DIGITS = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F', };
public static String encode(final byte[] bytes) {
StringBuilder stringBuilder = new StringBuilder(bytes.length * 2);
for (byte cur : bytes) {
stringBuilder.append(UPPER_HEX_DIGITS[(cur >> 4) & 0xF]);
stringBuilder.append(UPPER_HEX_DIGITS[(cur & 0xF)]);
}
return stringBuilder.toString();
}
private Hex() {
}
}