2626 * <p>This enum can be used to represent response status codes in a library-agnostic way, without
2727 * introducing dependencies on specific frameworks like Spring.
2828 *
29- * @see <a href="https://datatracker.ietf.org/doc/html/rfc9110#name-status-codes">RFC9110 - HTTP
30- * Semantics</a>
29+ * <p><b>Referenced RFC sources (chronological)</b>:
30+ *
31+ * <ul>
32+ * <li><b>1998-03</b> - RFC 2295: Transparent Content Negotiation in HTTP (<a
33+ * href="https://datatracker.ietf.org/doc/html/rfc2295">link</a>) - introduces 506 Variant
34+ * Also Negotiates.
35+ * <li><b>1998-04</b> - RFC 2324: Hyper Text Coffee Pot Control Protocol (HTCPCP/1.0) (<a
36+ * href="https://datatracker.ietf.org/doc/html/rfc2324">link</a>) - adds novelty code 418 I'm
37+ * a teapot.
38+ * <li><b>1999-02</b> - RFC 2518: HTTP Extensions for Distributed Authoring (WebDAV) (<a
39+ * href="https://datatracker.ietf.org/doc/html/rfc2518">link</a>) - defines 102 Processing,
40+ * 207 Multi-Status, 422 Unprocessable Entity, 423 Locked, 424 Failed Dependency.
41+ * <li><b>1999-06</b> - RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1 (Obsoleted) (<a
42+ * href="https://datatracker.ietf.org/doc/html/rfc2616">link</a>) - core set:
43+ * 100,101,200–206,300–305,400–417,500–505.
44+ * <li><b>2000-02</b> - RFC 2774: An HTTP Extension Framework (<a
45+ * href="https://datatracker.ietf.org/doc/html/rfc2774">link</a>) - adds 510 Not Extended.
46+ * <li><b>2002-01</b> - RFC 3229: Delta encoding in HTTP (<a
47+ * href="https://datatracker.ietf.org/doc/html/rfc3229">link</a>) - adds 226 IM Used.
48+ * <li><b>2007-06</b> - RFC 4918: WebDAV (replacing RFC 2518) (<a
49+ * href="https://datatracker.ietf.org/doc/html/rfc4918">link</a>) - re-specifies
50+ * 102,207,422,423,424; adds 507 Insufficient Storage.
51+ * <li><b>2010-05</b> - RFC 5842: Binding Extensions to WebDAV (<a
52+ * href="https://datatracker.ietf.org/doc/html/rfc5842">link</a>) - adds 208 Already Reported,
53+ * 508 Loop Detected.
54+ * <li><b>2012-04</b> - RFC 6585: Additional HTTP Status Codes (<a
55+ * href="https://datatracker.ietf.org/doc/html/rfc6585">link</a>) - adds 428 Precondition
56+ * Required, 429 Too Many Requests, 431 Request Header Fields Too Large, 511 Network
57+ * Authentication Required.
58+ * <li><b>2014-06</b> - RFC 7231: HTTP/1.1 Semantics and Content (<a
59+ * href="https://datatracker.ietf.org/doc/html/rfc7231">link</a>) - deprecates 305 Use Proxy;
60+ * renames 413 Request Entity Too Large → Payload Too Large; 414 Request-URI Too Long → URI
61+ * Too Long.
62+ * <li><b>2015-04</b> - RFC 7538: Status Code 308 (Permanent Redirect) (<a
63+ * href="https://datatracker.ietf.org/doc/html/rfc7538">link</a>) - adds 308 Permanent
64+ * Redirect.
65+ * <li><b>2015-05</b> - RFC 7540: HTTP/2 (<a
66+ * href="https://datatracker.ietf.org/doc/html/rfc7540">link</a>) - adds 421 Misdirected
67+ * Request.
68+ * <li><b>2016-02</b> - RFC 7725: An HTTP Status Code to Report Legal Obstacles (<a
69+ * href="https://datatracker.ietf.org/doc/html/rfc7725">link</a>) - adds 451 Unavailable For
70+ * Legal Reasons.
71+ * <li><b>2018-01</b> - RFC 8297: Indicating Hints (<a
72+ * href="https://datatracker.ietf.org/doc/html/rfc8297">link</a>) - adds 103 Early Hints;
73+ * obsoletes informal 103 Checkpoint name.
74+ * <li><b>2018-09</b> - RFC 8470: Using Early Data in HTTP (<a
75+ * href="https://datatracker.ietf.org/doc/html/rfc8470">link</a>) - adds 425 Too Early.
76+ * <li><b>2022-06</b> - RFC 9110: HTTP Semantics (<a
77+ * href="https://datatracker.ietf.org/doc/html/rfc9110">link</a>) - renames 413 Payload Too
78+ * Large → Content Too Large; 416 Requested Range Not Satisfiable → Range Not Satisfiable; 422
79+ * Unprocessable Entity → Unprocessable Content; consolidates prior semantics.
80+ * </ul>
81+ *
3182 * @see <a href="https://http.cat/">HTTP Cats</a>
3283 * @see <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Status">HTTP response
3384 * status codes - HTTP | MDN</a>
@@ -192,8 +243,8 @@ public enum ProblemStatus {
192243 NOT_MODIFIED (304 , "Not Modified" ),
193244
194245 /**
195- * @deprecated Obsoleted by RFC 7231. "Use Proxy" is no longer recommended.
196246 * @link <a href="https://datatracker.ietf.org/doc/html/rfc7231#section-6.4.5">RFC 7231 §6.4.5</a>
247+ * @deprecated Obsoleted by RFC 7231. "Use Proxy" is no longer recommended.
197248 */
198249 @ Deprecated
199250 USE_PROXY (305 , "Use Proxy" ),
@@ -320,9 +371,9 @@ public enum ProblemStatus {
320371 /**
321372 * 413 Request Entity Too Large.
322373 *
323- * @link <a href="https://datatracker.ietf.org/doc/html/rfc9110 #section-15.5 .14">RFC 9110
324- * §15.5 .14</a>
325- * @deprecated Renamed to {@link #CONTENT_TOO_LARGE} by RFC 8297 .
374+ * @link <a href="https://datatracker.ietf.org/doc/html/rfc2616 #section-10.4 .14">RFC 2616
375+ * §10.4 .14</a>
376+ * @deprecated Renamed to {@link #CONTENT_TOO_LARGE} in RFC 9110 .
326377 */
327378 @ Deprecated
328379 REQUEST_ENTITY_TOO_LARGE (413 , "Request Entity Too Large" ),
@@ -338,20 +389,20 @@ public enum ProblemStatus {
338389 /**
339390 * 414 Request URI Too Long.
340391 *
341- * @link <a href="https://datatracker.ietf.org/doc/html/rfc9110 #section-15.5 .15">RFC 9110
342- * §15.5 .15</a>
392+ * @link <a href="https://datatracker.ietf.org/doc/html/rfc2616 #section-10.4 .15">RFC 2616
393+ * §10.4 .15</a>
343394 * @deprecated Renamed to {@link #URI_TOO_LONG} by RFC 8297.
344395 */
345396 @ Deprecated
346- REQUEST_URI_TOO_LONG (414 , "Request URI Too Long" ),
397+ REQUEST_URI_TOO_LONG (414 , "Request- URI Too Long" ),
347398
348399 /**
349400 * 414 URI Too Long.
350401 *
351402 * @link <a href="https://datatracker.ietf.org/doc/html/rfc9110#section-15.5.15">RFC 9110
352403 * §15.5.15</a>
353404 */
354- URI_TOO_LONG (414 , "Request URI Too Long" ),
405+ URI_TOO_LONG (414 , "URI Too Long" ),
355406
356407 /**
357408 * 415 Unsupported Media Type.
@@ -364,8 +415,8 @@ public enum ProblemStatus {
364415 /**
365416 * 416 Requested Range Not Satisfiable.
366417 *
367- * @link <a href="https://datatracker.ietf.org/doc/html/rfc9110 #section-15.5 .17">RFC 9110
368- * §15 .5.17</a>
418+ * @link <a href="https://datatracker.ietf.org/doc/html/rfc2616 #section-10.4 .17">RFC 2616
419+ * §10 .5.17</a>
369420 */
370421 REQUESTED_RANGE_NOT_SATISFIABLE (416 , "Requested Range Not Satisfiable" ),
371422
@@ -520,7 +571,11 @@ public enum ProblemStatus {
520571 */
521572 NOT_EXTENDED (510 , "Not Extended" ),
522573
523- /** 511 Network Authentication Required. */
574+ /**
575+ * 511 Network Authentication Required.
576+ *
577+ * @link <a href="https://datatracker.ietf.org/doc/html/rfc6585#section-6">RFC 6585 §6</a>
578+ */
524579 NETWORK_AUTHENTICATION_REQUIRED (511 , "Network Authentication Required" );
525580
526581 /**
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