public void writeLongArray(DataOutput out, long [] array) throws IOException {
        writeObject(out, array);
    }
Writes an array of long values. This method handles the case when the
array is <tt>null</tt>.

@param out   the output stream.
@param array the array of long values.
@throws IOException if an error occurs.
xmppserver/src/main/java/org/jivesoftware/util/cache/DefaultExternalizableUtil.java