194 Cache Format

General Information

The 194 (RuneScape 2 beta) client worked with a very simple cache format. Each file in the cache was a file on the operating system.

Name hashing

Every name in the cache was hashed using the following method which is, incidentally, the similar to the way player names are converted to longs.

public static final long gethash(String string) {
    string = string.trim();
    long l = 0L;
    for (int i = 0; i < string.length() && i < 12; i++) {
        char c = string.charAt(i);
        l *= 37L;
        if (c >= 'A' && c <= 'Z')
            l += (long) ('\001' + c - 'A');
        else if (c >= 'a' && c <= 'z')
            l += (long) ('\001' + c - 'a');
        else if (c >= '0' && c <= '9')
            l += (long) ('\033' + c - '0');
    }
    return l;
}

The resulting long was converted to a string and the file was given that name.