Add "Java API Changes" session in HISTORY (#9055)

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/9055

Reviewed By: ajkr

Differential Revision: D31765398

Pulled By: jay-zhuang

fbshipit-source-id: 77ed67d69415c9fbbfc1132b15310b293e3939c6

HISTORY.md

@@ -11,7 +11,6 @@
 * Make `DB::close()` thread-safe.
 
 ### New Features
-* Add Java API bindings for new integrated BlobDB options
 * Print information about blob files when using "ldb list_live_files_metadata"
 * Provided support for SingleDelete with user defined timestamp.
 * Experimental new function DB::GetLiveFilesStorageInfo offers essentially a unified version of other functions like GetLiveFiles, GetLiveFilesChecksumInfo, and GetSortedWalFiles. Checkpoints and backups could show small behavioral changes and/or improved performance as they now use this new API.
@@ -19,7 +18,6 @@
 * Introduce an experimental feature to dump out the blocks from block cache and insert them to the secondary cache to reduce the cache warmup time (e.g., used while migrating DB instance). More information are in `class CacheDumper` and `CacheDumpedLoader` at `rocksdb/utilities/cache_dump_load.h` Note that, this feature is subject to the potential change in the future, it is still experimental.
 * Introduced a new BlobDB configuration option `blob_garbage_collection_force_threshold`, which can be used to trigger compactions targeting the SST files which reference the oldest blob files when the ratio of garbage in those blob files meets or exceeds the specified threshold. This can reduce space amplification with skewed workloads where the affected SST files might not otherwise get picked up for compaction.
 * Added EXPERIMENTAL support for table file (SST) unique identifiers that are stable and universally unique, available with new function `GetUniqueIdFromTableProperties`. Only SST files from RocksDB >= 6.24 support unique IDs.
-* [JAVA] `keyMayExist()` supports ByteBuffer.
 
 ### Public API change
 * Made SystemClock extend the Customizable class and added a CreateFromString method.  Implementations need to be registered with the ObjectRegistry and to implement a Name() method in order to be created via this method.
@@ -32,6 +30,11 @@
 ### Performance Improvements
 * Improved CPU efficiency of building block-based table (SST) files (#9039 and #9040).
 
+### Java API Changes
+* Add Java API bindings for new integrated BlobDB options
+* `keyMayExist()` supports ByteBuffer.
+* Fix multiget throwing Null Pointer Exception for num of keys > 70k (https://github.com/facebook/rocksdb/issues/8039).
+
 ## 6.25.0 (2021-09-20)
 ### Bug Fixes
 * Allow secondary instance to refresh iterator. Assign read seq after referencing SuperVersion.