Improved Meter.Id#getTags() performance

Signed-off-by: etki <[email protected]>

Author: etki

micrometer-core/src/main/java/io/micrometer/core/instrument/Meter.java

@@ -244,8 +244,7 @@ public Id withTags(Iterable<Tag> tags) {
         /**
          * Generate a new id replacing all tags with new ones.
          * @param tags The tags to add.
-         * @return A new id with the only the provided tags. The source id remains
-         * unchanged.
+         * @return A new id with only the provided tags. The source id remains unchanged.
          * @since 1.1.0
          */
         public Id replaceTags(Iterable<Tag> tags) {
@@ -282,8 +281,14 @@ public String getName() {
          * @return A set of dimensions that allows you to break down the name.
          */
         public List<Tag> getTags() {
-            List<Tag> tags = new ArrayList<>();
-            this.tags.forEach(tags::add);
+            if (this.tags == Tags.empty()) {
+                return Collections.emptyList();
+            }
+
+            List<Tag> tags = new ArrayList<>(32);
+            for (Tag tag : this.tags) {
+                tags.add(tag);
+            }
             return Collections.unmodifiableList(tags);
         }