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This mechanism supports extensibility; implementations of future versions 079 * of the HTTP protocol might apply these directives to header fields not defined in HTTP/1.1. 080 * 081 * <p> 082 * The cache-control directives can be broken down into these general categories: 083 * <ul> 084 * <li>Restrictions on what are cacheable; these may only be imposed by the origin server. 085 * <li>Restrictions on what may be stored by a cache; these may be imposed by either the origin server or the user 086 * agent. 087 * <li>Modifications of the basic expiration mechanism; these may be imposed by either the origin server or the 088 * user agent. 089 * <li>Controls over cache revalidation and reload; these may only be imposed by a user agent. 090 * <li>Control over transformation of entities. 091 * <li>Extensions to the caching system. 092 * </ul> 093 * 094 * <h5 class='section'>See Also:</h5><ul> 095 * <li class='link'><a class="doclink" href="../../../../../index.html#juneau-rest-common">juneau-rest-common</a> 096 * <li class='extlink'><a class="doclink" href="https://www.w3.org/Protocols/rfc2616/rfc2616.html">Hypertext Transfer Protocol -- HTTP/1.1</a> 097 * </ul> 098 * 099 * @serial exclude 100 */ 101@Header("Cache-Control") 102public class CacheControl extends BasicStringHeader { 103 104 //----------------------------------------------------------------------------------------------------------------- 105 // Static 106 //----------------------------------------------------------------------------------------------------------------- 107 108 private static final long serialVersionUID = 1L; 109 private static final String NAME = "Cache-Control"; 110 111 /** 112 * Static creator. 113 * 114 * @param value 115 * The header value. 116 * <br>Can be <jk>null</jk>. 117 * @return A new header bean, or <jk>null</jk> if the value is <jk>null</jk>. 118 */ 119 public static CacheControl of(String value) { 120 return value == null ? null : new CacheControl(value); 121 } 122 123 /** 124 * Static creator with delayed value. 125 * 126 * <p> 127 * Header value is re-evaluated on each call to {@link #getValue()}. 128 * 129 * @param value 130 * The supplier of the header value. 131 * <br>Can be <jk>null</jk>. 132 * @return A new header bean, or <jk>null</jk> if the value is <jk>null</jk>. 133 */ 134 public static CacheControl of(Supplier<String> value) { 135 return value == null ? null : new CacheControl(value); 136 } 137 138 //----------------------------------------------------------------------------------------------------------------- 139 // Instance 140 //----------------------------------------------------------------------------------------------------------------- 141 142 /** 143 * Constructor. 144 * 145 * @param value 146 * The header value. 147 * <br>Can be <jk>null</jk>. 148 */ 149 public CacheControl(String value) { 150 super(NAME, value); 151 } 152 153 /** 154 * Constructor with delayed value. 155 * 156 * <p> 157 * Header value is re-evaluated on each call to {@link #getValue()}. 158 * 159 * @param value 160 * The supplier of the header value. 161 * <br>Can be <jk>null</jk>. 162 */ 163 public CacheControl(Supplier<String> value) { 164 super(NAME, value); 165 } 166}