001// ***************************************************************************************************************************
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006// *                                                                                                                         *
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012// ***************************************************************************************************************************
013package org.apache.juneau.http;
014
015/**
016 * Represents a parsed <l>Accept-Range</l> HTTP response header.
017 * 
018 * <p>
019 * What partial content range types this server supports via byte serving.
020 * 
021 * <h5 class='figure'>Example</h5>
022 * <p class='bcode'>
023 *    Accept-Ranges: bytes
024 * </p>
025 * 
026 * <h5 class='topic'>RFC2616 Specification</h5>
027 * 
028 * The Accept-Ranges response-header field allows the server to indicate its acceptance of range requests for a
029 * resource:
030 * <p class='bcode'>
031 *    Accept-Ranges     = "Accept-Ranges" ":" acceptable-ranges
032 *    acceptable-ranges = 1#range-unit | "none"
033 * </p>
034 * 
035 * <p>
036 * Origin servers that accept byte-range requests MAY send...
037 * <p class='bcode'>
038 *    Accept-Ranges: bytes
039 * </p>
040 * <p>
041 * ...but are not required to do so.
042 * 
043 * <p>
044 * Clients MAY generate byte-range requests without having received this header for the resource involved.
045 * 
046 * <p>
047 * Range units are defined in section 3.12.
048 * 
049 * <p>
050 * Servers that do not accept any kind of range request for a resource MAY send...
051 * <p class='bcode'>
052 *    Accept-Ranges: none
053 * </p>
054 * <p>
055 * ...to advise the client not to attempt a range request.
056 * 
057 * <h5 class='section'>See Also:</h5>
058 * <ul class='doctree'>
059 *    <li class='extlink'><a class='doclink' href='https://www.w3.org/Protocols/rfc2616/rfc2616.html'>Hypertext Transfer Protocol -- HTTP/1.1</a>
060 * </ul>
061 */
062public final class AcceptRanges extends HeaderString {
063
064   /**
065    * Returns a parsed <code>Accept-Ranges</code> header.
066    * 
067    * @param value The <code>Accept-Ranges</code> header string.
068    * @return The parsed <code>Accept-Ranges</code> header, or <jk>null</jk> if the string was null.
069    */
070   public static AcceptRanges forString(String value) {
071      if (value == null)
072         return null;
073      return new AcceptRanges(value);
074   }
075
076   private AcceptRanges(String value) {
077      super(value);
078   }
079}