A bit more javadoc

Author: JonasKunz

libs/exponential-histogram/src/main/java/org/elasticsearch/exponentialhistogram/MergingBucketIterator.java

@@ -9,6 +9,10 @@
 
 package org.elasticsearch.exponentialhistogram;
 
+/**
+ * Iterates over two sets of buckets in parallel, bringing them to the same scale
+ * and merging buckets which exist in both.
+ */
 final class MergingBucketIterator implements ExponentialHistogram.BucketIterator {
 
     private final ExponentialHistogram.BucketIterator itA;

libs/exponential-histogram/src/main/java/org/elasticsearch/exponentialhistogram/ScaleAdjustingBucketIterator.java

@@ -11,6 +11,11 @@
 
 import static org.elasticsearch.exponentialhistogram.ExponentialScaleUtils.adjustScale;
 
+/**
+ * Iterates over buckets while also adjusting the scale.
+ * When scaling down, this can cause multiple buckets to collapse into a single one.
+ * This iterator ensures that they are properly merged in this case.
+ */
 final class ScaleAdjustingBucketIterator implements ExponentialHistogram.BucketIterator {
 
     private final ExponentialHistogram.BucketIterator delegate;