Updated release notes for HttpClient 5.4-alpha1 release

RELEASE_NOTES.txt

@@ -1,4 +1,105 @@
-Release 5.3
+Release 5.4 ALPHA1
+-------------------
+
+This is the first ALPHA release in the 5.3 release series that improves HTTP protocol support
+by ensuring conformance to the latest HTTP specification (RFC 9110, RFC 9111, RFC 7616,
+RFC 7617), ensures compatibility with Java Virtual Threads by replacing 'synchronized' keywords
+in critical sections with Java lock primitives. The HTTP caching protocol layer has also been
+redesigned and overhauled to improve cache efficiency and optimize performance.
+
+IMPORTANT! Please note the new cache entry serialization format is incompatible with earlier
+versions of HttpClient Cache. Persistent caches (file system based, Memcached, EhCAche
+with object serialization) created with any earlier version MUST be flushed and re-populated
+or the cache backend MUST be configured to use the old deprecated cache entry serializer.
+
+
+Notable changes and features included in the 5.3 series:
+
+* Improved conformance to RFC 9110 (HTTP Semantics), RFC 7616 (HTTP Digest Access
+  Authentication), RFC 2617 (’Basic’ HTTP Authentication Scheme).
+
+* UTF-8 encoding to be used by default for text where appropriate.
+
+* Compatibility with Java Virtual Threads and Java 21 Runtime.
+
+* Redesign and rewrite of the HTTP caching protocol layer for better efficiency
+  and improved conformance to RFC 9111 (HTTP Caching).
+
+
+Change Log
+-------------------
+
+* `username*` validation and decoding in DigestScheme as per RFC (#511).
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+* Support for Userhash parameter in Digest authentication as per RFC 7616 (#509).
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+* Enforce UTF-8 encoding in Digest authentication according to RFC 7616 (#508).
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+* Enforce UTF-8 encoding in BasicSchemeFactory as per RFC 7617 (#506).
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+* Stricter password validation in BasicScheme (#505).
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+* Bug fix: When validating a cache entry the protocol handlers must use the current request
+  message with additional headers generated by the previous request interceptors instead of
+  the original request message.
+  Contributed by Oleg Kalnichevski <olegk at apache.org>
+
+* Better debug logging in the caching protocol handlers.
+  Contributed by Oleg Kalnichevski <olegk at apache.org>
+
+* Better HTTP execution context management by caching protocol handlers.
+  Contributed by Oleg Kalnichevski <olegk at apache.org>
+
+* HTTPCLIENT-2301. Fixed a concurrency defect in the connection release code of
+  BasicHttpClientConnectionManager.
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+* HttpCacheEntry to cache parsed DATE, EXPIRES, and LAST_MODIFIED values; avoid parsing
+  DATE header of cache entries and HTTP messages multiple times.
+  Contributed by Oleg Kalnichevski <olegk at apache.org>
+
+* HTTPCLIENT-2293: Via header protocol improvements and performance optimization.
+  Contributed by Oleg Kalnichevski <olegk at apache.org>
+
+* HTTPCLIENT-2293: RFC-compliant TRACE request interceptor (#486).
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+* HTTPCLIENT-2293: 'If-Range' request validation as per RFC 9110 (#485).
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+* HTTPCLIENT-2293: Enforce port specification for CONNECT requests as per RFC 9110 (#482).
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+* HTTPCLIENT-2284: Internal cache storage improvements (#478).
+  Contributed by Oleg Kalnichevski <olegk at apache.org>
+
+* Replace `synchronized` blocks with ReentrantLock to ensure compatibility with virtual
+  threads (#476).
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+* HTTPCLIENT-2284: Cache entry representation improvements: (#477).
+  Contributed by Oleg Kalnichevski <olegk at apache.org>
+
+* HTTPCLIENT-2277: Rewrite the caching protocol layer for improved efficiency and
+  conformance to RFC 9111.
+  Contributed by Arturo Bernal <[email protected]> and
+  Oleg Kalnichevski <olegk at apache.org> and
+
+* Request and response Cache-Control APIs
+  Contributed by Arturo Bernal <[email protected]> and
+  Oleg Kalnichevski <olegk at apache.org> and
+
+* HttpByteArrayCacheEntrySerializer refactoring and performance improvements.
+  Contributed by Arturo Bernal <abernal at apache.org>
+
+
+
+Release 5.3
 -------------------
 
 This is the first GA release in the 5.3 release series. This release finalizes the 5.3 APIs
@@ -135,7 +236,7 @@ Release 5.2
 ------------------
 
 This is the first GA release in the 5.2 release series. This release finalizes the 5.2 APIs
-and corrects a number of defects discovered since the previous release.
+and corrects several defects discovered since the previous release.
 
 Please note that 5.2 upgrades the minimal JRE level to version 8 (8u251 is required).