"application/dialog-info+xml",
				"application/dicom",
				"application/dita+xml",
				"application/dita+xml;format=map",
				"application/dita+xml;format=topic",
				"application/dita+xml;format=task",
				"application/dita+xml;format=concept",
				"application/dita+xml;format=val",
				"application/dns",
				"application/dvcs",
				"application/ecmascript",
				"application/edi-consent",

    private final List<Header> requestHeaderList = new ArrayList<>();

    /** Map of HTTP client properties */
    private final Map<String, Object> httpClientPropertyMap = new HashMap<>();

    /** Task for monitoring idle connections */
    private TimeoutTask connectionMonitorTask;

    /** Connection timeout in milliseconds */
    protected Integer connectionTimeout;