001// ***************************************************************************************************************************
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006// *                                                                                                                         *
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012// ***************************************************************************************************************************
013package org.apache.juneau.http;
014
015/**
016 * Represents a parsed <l>Server</l> HTTP response header.
017 * 
018 * <p>
019 * A name for the server.
020 * 
021 * <h5 class='figure'>Example</h5>
022 * <p class='bcode'>
023 *    Server: Apache/2.4.1 (Unix)
024 * </p>
025 * 
026 * <h5 class='topic'>RFC2616 Specification</h5>
027 * 
028 * The Server response-header field contains information about the software used by the origin server to handle the
029 * request.
030 * The field can contain multiple product tokens (section 3.8) and comments identifying the server and any significant
031 * sub-products.
032 * The product tokens are listed in order of their significance for identifying the application.
033 * 
034 * <p class='bcode'>
035 *    Server         = "Server" ":" 1*( product | comment )
036 * </p>
037 * 
038 * <p>
039 * Example:
040 * <p class='bcode'>
041 *    Server: CERN/3.0 libwww/2.17
042 * </p>
043 * 
044 * <p>
045 * If the response is being forwarded through a proxy, the proxy application MUST NOT modify the Server response-header.
046 * Instead, it SHOULD include a Via field (as described in section 14.45).
047 * 
048 * <p>
049 * Note: Revealing the specific software version of the server might allow the server machine to become more vulnerable
050 * to attacks against software that is known to contain security holes.
051 * Server implementors are encouraged to make this field a configurable option.
052 * 
053 * <h5 class='section'>See Also:</h5>
054 * <ul class='doctree'>
055 *    <li class='extlink'><a class='doclink' href='https://www.w3.org/Protocols/rfc2616/rfc2616.html'>Hypertext Transfer Protocol -- HTTP/1.1</a>
056 * </ul>
057 */
058public final class Server extends HeaderString {
059
060   /**
061    * Returns a parsed <code>Server</code> header.
062    * 
063    * @param value The <code>Server</code> header string.
064    * @return The parsed <code>Server</code> header, or <jk>null</jk> if the string was null.
065    */
066   public static Server forString(String value) {
067      if (value == null)
068         return null;
069      return new Server(value);
070   }
071
072   private Server(String value) {
073      super(value);
074   }
075}