public long readUInt() throws IOException {
        return ((in.read() & 0xff)
                | ((in.read() & 0xff) << 8)
                | ((in.read() & 0xff) << 16)
                | (((long) (in.read() & 0xff)) << 24));
    }
read an unsigned int as a long

@return the value that was read
@throws IOException if an I/O error occurs while reading
jme3-core/src/main/java/com/jme3/util/LittleEndien.java