if ((offset & 0x7fffffff) >= this.length())
offset &= 0x7fffffff; if (offset >= this.length())
    public int read(int offset)    {        if ((offset & 0x7fffffff) >= this.length()) //don't write past the end        // of the ROM        {            //			System.out.println(            //				"Attempted read past end of rom, (0x"            //					+ Integer.toHexString(offset)            //					+ ")");            return -1;        }        return this.rom[offset] & 255;    }