public long getContentLength() {
		String length = (String) metadata.get("Content-Length");
		if (length == null) {
			return -1L;
		}
		Long longLength = -1L;
		try {
			longLength = Long.decode((String) length);
		} catch (NumberFormatException e) {
			logger.error("NumberFormatException:" + length, e);
		}
		return longLength;
	}