From 36995d991a79d1f00195b0199961d67fe401fcd9 Mon Sep 17 00:00:00 2001
From: Sumeet Varma <sumeet.varma@databricks.com>
Date: Mon, 23 Sep 2024 16:02:00 -0700
Subject: [PATCH] [Storage] Add Javadoc for
 CoordinatedCommitsUtils::getCoordinatorName (#3711)

#### Which Delta project/connector is this regarding?

- [ ] Spark
- [ ] Standalone
- [ ] Flink
- [ ] Kernel
- [x] Other (Storage)

## Description
This is a simple cleanup PR for improving documentation of
getCoordinatorName

1. Return an Optional<String> to indicate the method may return null if
no coordinator is set
2. Rename the method from getCoordinator -> getCoordinatorName

## How was this patch tested?

Build

## Does this PR introduce _any_ user-facing changes?

No
---
 .../storage/commit/CoordinatedCommitsUtils.java   | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/storage/src/main/java/io/delta/storage/commit/CoordinatedCommitsUtils.java b/storage/src/main/java/io/delta/storage/commit/CoordinatedCommitsUtils.java
index bb27823a5f..cdd03d5ed7 100644
--- a/storage/src/main/java/io/delta/storage/commit/CoordinatedCommitsUtils.java
+++ b/storage/src/main/java/io/delta/storage/commit/CoordinatedCommitsUtils.java
@@ -68,9 +68,9 @@ public static boolean isCoordinatedCommitsToFSConversion(
             Long commitVersion,
             UpdatedActions updatedActions) {
         boolean oldMetadataHasCoordinatedCommits =
-                !getCoordinator(updatedActions.getOldMetadata()).isEmpty();
+                getCoordinatorName(updatedActions.getOldMetadata()).isPresent();
         boolean newMetadataHasCoordinatedCommits =
-                !getCoordinator(updatedActions.getNewMetadata()).isEmpty();
+                getCoordinatorName(updatedActions.getNewMetadata()).isPresent();
         return oldMetadataHasCoordinatedCommits && !newMetadataHasCoordinatedCommits && commitVersion > 0;
     }
 
@@ -120,10 +120,17 @@ public static Path commitDirPath(Path logPath) {
         return new Path(logPath, COMMIT_SUBDIR);
     }
 
-    public static String getCoordinator(AbstractMetadata metadata) {
+    /**
+     * Retrieves the coordinator name from the provided abstract metadata.
+     * If no coordinator is set, an empty optional is returned.
+     *
+     * @param metadata The abstract metadata from which to retrieve the coordinator name.
+     * @return The coordinator name if set, otherwise an empty optional.
+     */
+    public static Optional<String> getCoordinatorName(AbstractMetadata metadata) {
         String coordinator = metadata
                 .getConfiguration()
                 .get(COORDINATED_COMMITS_COORDINATOR_NAME_KEY);
-        return coordinator != null ? coordinator : "";
+        return Optional.ofNullable(coordinator);
     }
 }