diff --git a/pom.xml b/pom.xml
index d858e9cb1..84e032947 100644
--- a/pom.xml
+++ b/pom.xml
@@ -190,7 +190,7 @@ under the License.
               <configuration>
                 <rules>
                   <requireJavaVersion>
-                    <version>${java.version}</version>
+                    <version>[21,)</version> <!-- java.version -->
                   </requireJavaVersion>
                   <requireMavenVersion>
                     <version>[${maven.version},4.0.0)</version>
@@ -237,9 +237,10 @@ under the License.
           <configuration>
             <docfilessubdirs>true</docfilessubdirs>
             <show>public</show>
-            <additionalOptions>
-              <additionalOption>${jvm-ffm-flag}</additionalOption>
-            </additionalOptions>
+            <doclint>all,-missing</doclint>
+            <additionalJOptions>
+              <additionalJOption>${jvm-ffm-flag}</additionalJOption>
+            </additionalJOptions>
           </configuration>
           <executions>
             <execution>
diff --git a/src/main/java/org/apache/datasketches/common/Family.java b/src/main/java/org/apache/datasketches/common/Family.java
index 225248997..829a95960 100644
--- a/src/main/java/org/apache/datasketches/common/Family.java
+++ b/src/main/java/org/apache/datasketches/common/Family.java
@@ -194,7 +194,7 @@ public int getID() {
   }
 
   /**
-   *
+   * Checks the given Family ID
    * @param id the given id, a value &lt; 128.
    */
   public void checkFamilyID(final int id) {
diff --git a/src/main/java/org/apache/datasketches/cpc/MergingValidation.java b/src/main/java/org/apache/datasketches/cpc/MergingValidation.java
index dae3670ea..213e65d30 100644
--- a/src/main/java/org/apache/datasketches/cpc/MergingValidation.java
+++ b/src/main/java/org/apache/datasketches/cpc/MergingValidation.java
@@ -56,7 +56,7 @@ public class MergingValidation {
   private PrintWriter printWriter;
 
   /**
-   *
+   * Constructor
    * @param lgMinK lgMinK
    * @param lgMaxK lgMaxK
    * @param lgMulK lgMulK
@@ -79,7 +79,7 @@ public MergingValidation(final int lgMinK, final int lgMaxK, final int lgMulK, f
   }
 
   /**
-   *
+   * Start the merging validation process
    */
   public void start() {
     printf(hfmt, (Object[]) hStrArr); //print header
diff --git a/src/main/java/org/apache/datasketches/cpc/QuickMergingValidation.java b/src/main/java/org/apache/datasketches/cpc/QuickMergingValidation.java
index 389f3e4dd..e2bb8605f 100644
--- a/src/main/java/org/apache/datasketches/cpc/QuickMergingValidation.java
+++ b/src/main/java/org/apache/datasketches/cpc/QuickMergingValidation.java
@@ -54,7 +54,7 @@ public class QuickMergingValidation {
   private PrintWriter printWriter;
 
   /**
-   *
+   * Constructor
    * @param lgMinK lgMinK
    * @param lgMaxK lgMaxK
    * @param incLgK incLgK
@@ -73,7 +73,7 @@ public QuickMergingValidation(final int lgMinK, final int lgMaxK, final int incL
   }
 
   /**
-   *
+   * Start the Quick Merging Validation process
    */
   public void start() {
     printf(hfmt, (Object[]) hStrArr); //print header
diff --git a/src/main/java/org/apache/datasketches/cpc/StreamingValidation.java b/src/main/java/org/apache/datasketches/cpc/StreamingValidation.java
index 97dc4a9b2..aab6e5e6f 100644
--- a/src/main/java/org/apache/datasketches/cpc/StreamingValidation.java
+++ b/src/main/java/org/apache/datasketches/cpc/StreamingValidation.java
@@ -57,7 +57,7 @@ public class StreamingValidation {
   private BitMatrix matrix = null;
 
   /**
-   *
+   * Constructor
    * @param lgMinK lgMinK
    * @param lgMaxK lgMaxK
    * @param trials trials
@@ -78,7 +78,7 @@ public StreamingValidation(final int lgMinK, final int lgMaxK, final int trials,
   }
 
   /**
-   *
+   * Start the streaming validation process
    */
   public void start() {
     printf(hfmt, (Object[]) hStrArr);
diff --git a/src/main/java/org/apache/datasketches/cpc/TestUtil.java b/src/main/java/org/apache/datasketches/cpc/TestUtil.java
index 0a96db768..442e3ffe6 100644
--- a/src/main/java/org/apache/datasketches/cpc/TestUtil.java
+++ b/src/main/java/org/apache/datasketches/cpc/TestUtil.java
@@ -25,6 +25,7 @@
 import static org.apache.datasketches.cpc.RuntimeAsserts.rtAssertEquals;
 
 /**
+ * Utility methods for Test
  * @author Lee Rhodes
  */
 public class TestUtil {
diff --git a/src/main/java/org/apache/datasketches/fdt/Group.java b/src/main/java/org/apache/datasketches/fdt/Group.java
index 67017699d..e22ee2398 100644
--- a/src/main/java/org/apache/datasketches/fdt/Group.java
+++ b/src/main/java/org/apache/datasketches/fdt/Group.java
@@ -66,41 +66,49 @@ public Group init(final String priKey, final int count, final double estimate, f
   }
 
   /**
-   * @return priKey of type T
+   * Gets the primary key of type String
+   * @return priKey of type String
    */
   public String getPrimaryKey() { return priKey; }
 
   /**
+   * Returns the count
    * @return the count
    */
   public int getCount() { return count; }
 
   /**
+   * Returns the estimate
    * @return the estimate
    */
   public double getEstimate() { return est; }
 
   /**
+   * Returns the upper bound
    * @return the upper bound
    */
   public double getUpperBound() { return ub; }
 
   /**
+   * Returns the lower bound
    * @return the lower bound
    */
   public double getLowerBound() { return lb; }
 
   /**
+   * Returns the fraction for this group
    * @return the fraction for this group
    */
   public double getFraction() { return fraction; }
 
   /**
+   * Returns the RSE
    * @return the RSE
    */
   public double getRse() { return rse; }
 
   /**
+   * Returns the descriptive header
    * @return the descriptive header
    */
   public String getHeader() {
@@ -112,9 +120,6 @@ public String toString() {
     return String.format(fmt, count, est, ub, lb, fraction, rse, priKey);
   }
 
-  /**
-   * @param that The Group to compare to
-   */
   @Override
   public int compareTo(final Group that) {
     return that.count - count; //decreasing
@@ -133,4 +138,3 @@ public int hashCode() {
   }
 
 }
-
diff --git a/src/main/java/org/apache/datasketches/frequencies/ItemsSketch.java b/src/main/java/org/apache/datasketches/frequencies/ItemsSketch.java
index b2648b943..042612e42 100644
--- a/src/main/java/org/apache/datasketches/frequencies/ItemsSketch.java
+++ b/src/main/java/org/apache/datasketches/frequencies/ItemsSketch.java
@@ -397,6 +397,7 @@ public Row<T>[] getFrequentItems(final ErrorType errorType) {
   }
 
   /**
+   * Returns an upper bound on the maximum error of getEstimate(item) for any item.
    * @return An upper bound on the maximum error of getEstimate(item) for any item.
    * This is equivalent to the maximum distance between the upper bound and the lower bound
    * for any item.
@@ -415,6 +416,7 @@ public int getMaximumMapCapacity() {
   }
 
   /**
+   * Returns the number of active items in the sketch.
    * @return the number of active items in the sketch.
    */
   public int getNumActiveItems() {
@@ -624,26 +626,31 @@ public static class Row<T> implements Comparable<Row<T>> {
     }
 
     /**
+     * Returns an item of type T
      * @return item of type T
      */
     public T getItem() { return item; }
 
     /**
+     * Returns the estimate
      * @return the estimate
      */
     public long getEstimate() { return est; }
 
     /**
+     * Returns the upper bound
      * @return the upper bound
      */
     public long getUpperBound() { return ub; }
 
     /**
+     * Returns the lower bound
      * @return return the lower bound
      */
     public long getLowerBound() { return lb; }
 
     /**
+     * Returns the descriptive row header
      * @return the descriptive row header
      */
     public static String getRowHeader() {
diff --git a/src/main/java/org/apache/datasketches/frequencies/LongsSketch.java b/src/main/java/org/apache/datasketches/frequencies/LongsSketch.java
index 7d1990b62..1fdc52894 100644
--- a/src/main/java/org/apache/datasketches/frequencies/LongsSketch.java
+++ b/src/main/java/org/apache/datasketches/frequencies/LongsSketch.java
@@ -439,6 +439,7 @@ public Row[] getFrequentItems(final ErrorType errorType) {
   }
 
   /**
+   * Returns an upper bound on the maximum error of getEstimate(item) for any item.
    * @return An upper bound on the maximum error of getEstimate(item) for any item.
    * This is equivalent to the maximum distance between the upper bound and the lower bound
    * for any item.
@@ -457,6 +458,7 @@ public int getMaximumMapCapacity() {
   }
 
   /**
+   * Returns the number of active items in the sketch.
    * @return the number of active items in the sketch.
    */
   public int getNumActiveItems() {
@@ -693,26 +695,31 @@ public static class Row implements Comparable<Row> {
     }
 
     /**
-     * @return item of type T
+     * Returns item of type long
+     * @return item of type long
      */
     public long getItem() { return item; }
 
     /**
+     * Returns the estimate
      * @return the estimate
      */
     public long getEstimate() { return est; }
 
     /**
+     * Returns the upper bound
      * @return the upper bound
      */
     public long getUpperBound() { return ub; }
 
     /**
+     * Returns the lower bound
      * @return return the lower bound
      */
     public long getLowerBound() { return lb; }
 
     /**
+     * Returns the descriptive row header
      * @return the descriptive row header
      */
     public static String getRowHeader() {
diff --git a/src/main/java/org/apache/datasketches/quantiles/UpdateDoublesSketch.java b/src/main/java/org/apache/datasketches/quantiles/UpdateDoublesSketch.java
index f56c3b352..f7191402d 100644
--- a/src/main/java/org/apache/datasketches/quantiles/UpdateDoublesSketch.java
+++ b/src/main/java/org/apache/datasketches/quantiles/UpdateDoublesSketch.java
@@ -23,6 +23,7 @@
 import org.apache.datasketches.memory.WritableMemory;
 
 /**
+ * Extends DoubleSketch
  * @author Jon Malkin
  */
 public abstract class UpdateDoublesSketch extends DoublesSketch {
@@ -61,6 +62,7 @@ public static UpdateDoublesSketch heapify(final Memory srcMem) {
   }
 
   /**
+   * Returns a CompactDoublesSketch of this class
    * @return a CompactDoublesSketch of this class
    */
   public CompactDoublesSketch compact() {
diff --git a/src/main/java/org/apache/datasketches/quantilescommon/QuantilesGenericAPI.java b/src/main/java/org/apache/datasketches/quantilescommon/QuantilesGenericAPI.java
index bc0881282..c6a05ffa1 100644
--- a/src/main/java/org/apache/datasketches/quantilescommon/QuantilesGenericAPI.java
+++ b/src/main/java/org/apache/datasketches/quantilescommon/QuantilesGenericAPI.java
@@ -78,6 +78,7 @@ default double[] getCDF(T[] splitPoints) {
   double[] getCDF(T[] splitPoints, QuantileSearchCriteria searchCrit);
 
   /**
+   * Returns the sketch item class
    * @return the sketch item class
    */
   Class<T> getClassOfT();
diff --git a/src/main/java/org/apache/datasketches/sampling/SampleSubsetSummary.java b/src/main/java/org/apache/datasketches/sampling/SampleSubsetSummary.java
index b7758b148..1504542f7 100644
--- a/src/main/java/org/apache/datasketches/sampling/SampleSubsetSummary.java
+++ b/src/main/java/org/apache/datasketches/sampling/SampleSubsetSummary.java
@@ -41,13 +41,15 @@ public class SampleSubsetSummary {
   }
 
   /**
-   * @return the Lower Bound
+   * Returns the lower bound
+   * @return the lower bound
    */
   public double getLowerBound() {
     return lowerBound;
   }
 
   /**
+   * Returns the total sketch weight
    * @return the total sketch weight
    */
   public double getTotalSketchWeight() {
@@ -55,13 +57,15 @@ public double getTotalSketchWeight() {
   }
 
   /**
-   * @return the Upper Bound
+   * Returns the upper bound
+   * @return the upper bound
    */
   public double getUpperBound() {
     return upperBound;
   }
 
   /**
+   * Returns the unique count estimate
    * @return the unique count estimate
    */
   public double getEstimate() {
diff --git a/src/main/java/org/apache/datasketches/tdigest/TDigestDouble.java b/src/main/java/org/apache/datasketches/tdigest/TDigestDouble.java
index 951bd7244..d44a439d1 100644
--- a/src/main/java/org/apache/datasketches/tdigest/TDigestDouble.java
+++ b/src/main/java/org/apache/datasketches/tdigest/TDigestDouble.java
@@ -86,6 +86,7 @@ public TDigestDouble(final short k) {
   }
 
   /**
+   * Returns parameter k (compression) that was used to configure this TDigest
    * @return parameter k (compression) that was used to configure this TDigest
    */
   public short getK() {
@@ -137,6 +138,7 @@ private void compress() {
   }
 
   /**
+   * Returns true if TDigest has not seen any data
    * @return true if TDigest has not seen any data
    */
   public boolean isEmpty() {
@@ -144,6 +146,7 @@ public boolean isEmpty() {
   }
 
   /**
+   * Returns minimum value seen by TDigest
    * @return minimum value seen by TDigest
    */
   public double getMinValue() {
@@ -152,6 +155,7 @@ public double getMinValue() {
   }
 
   /**
+   * Returns maximum value seen by TDigest
    * @return maximum value seen by TDigest
    */
   public double getMaxValue() {
@@ -160,6 +164,7 @@ public double getMaxValue() {
   }
 
   /**
+   * Returns total weight
    * @return total weight
    */
   public long getTotalWeight() {
diff --git a/src/main/java/org/apache/datasketches/theta/AnotB.java b/src/main/java/org/apache/datasketches/theta/AnotB.java
index 322e66ef7..d9ab37416 100644
--- a/src/main/java/org/apache/datasketches/theta/AnotB.java
+++ b/src/main/java/org/apache/datasketches/theta/AnotB.java
@@ -56,6 +56,11 @@
  */
 public abstract class AnotB extends SetOperation {
 
+  /**
+   * Constructor
+   */
+  AnotB() {}
+
   @Override
   public Family getFamily() {
     return Family.A_NOT_B;
diff --git a/src/main/java/org/apache/datasketches/theta/SetOperation.java b/src/main/java/org/apache/datasketches/theta/SetOperation.java
index b89ca9703..c198dceb7 100644
--- a/src/main/java/org/apache/datasketches/theta/SetOperation.java
+++ b/src/main/java/org/apache/datasketches/theta/SetOperation.java
@@ -39,6 +39,9 @@
 public abstract class SetOperation implements MemoryStatus {
   static final int CONST_PREAMBLE_LONGS = 3;
 
+  /**
+   * Constructor
+   */
   SetOperation() {}
 
   /**
diff --git a/src/main/java/org/apache/datasketches/thetacommon/HashOperations.java b/src/main/java/org/apache/datasketches/thetacommon/HashOperations.java
index 848bb47ed..f6b22cb50 100644
--- a/src/main/java/org/apache/datasketches/thetacommon/HashOperations.java
+++ b/src/main/java/org/apache/datasketches/thetacommon/HashOperations.java
@@ -287,6 +287,7 @@ public static int hashSearchOrInsertMemory(final WritableMemory wmem, final int
   //Other related methods
 
   /**
+   * Checks that the given theta is not negative nor zero.
    * @param thetaLong must be greater than zero otherwise throws an exception.
    * <a href="{@docRoot}/resources/dictionary.html#thetaLong">See Theta Long</a>
    */
@@ -299,6 +300,7 @@ public static void checkThetaCorruption(final long thetaLong) {
   }
 
   /**
+   * Checks that the given hash value is not negative.
    * @param hash must be greater than -1 otherwise throws an exception.
    * Note a hash of zero is normally ignored, but a negative hash is never allowed.
    */
diff --git a/src/main/java/org/apache/datasketches/tuple/DeserializeResult.java b/src/main/java/org/apache/datasketches/tuple/DeserializeResult.java
index 21adb45e2..db8ad682b 100644
--- a/src/main/java/org/apache/datasketches/tuple/DeserializeResult.java
+++ b/src/main/java/org/apache/datasketches/tuple/DeserializeResult.java
@@ -38,6 +38,7 @@ public DeserializeResult(final T object, final int size) {
   }
 
   /**
+   * Returns Deserialized object
    * @return Deserialized object
    */
   public T getObject() {
@@ -45,7 +46,8 @@ public T getObject() {
   }
 
   /**
-   * @return Size in bytes occupied by the object in the serialized form
+   * Returns size in bytes occupied by the object in the serialized form
+   * @return size in bytes occupied by the object in the serialized form
    */
   public int getSize() {
     return size;
diff --git a/src/main/java/org/apache/datasketches/tuple/Sketch.java b/src/main/java/org/apache/datasketches/tuple/Sketch.java
index dcc7a2c16..f0003bf3c 100644
--- a/src/main/java/org/apache/datasketches/tuple/Sketch.java
+++ b/src/main/java/org/apache/datasketches/tuple/Sketch.java
@@ -145,6 +145,7 @@ public boolean isEstimationMode() {
   }
 
   /**
+   * Returns number of retained entries
    * @return number of retained entries
    */
   public abstract int getRetainedEntries();
diff --git a/src/main/java/org/apache/datasketches/tuple/Sketches.java b/src/main/java/org/apache/datasketches/tuple/Sketches.java
index b4c1eed14..fba8ab604 100644
--- a/src/main/java/org/apache/datasketches/tuple/Sketches.java
+++ b/src/main/java/org/apache/datasketches/tuple/Sketches.java
@@ -28,6 +28,7 @@
 public final class Sketches {
 
   /**
+   * Creates an empty sketch.
    * @param <S> Type of Summary
    * @return an empty instance of Sketch
    */
diff --git a/src/main/java/org/apache/datasketches/tuple/SummaryFactory.java b/src/main/java/org/apache/datasketches/tuple/SummaryFactory.java
index 4b20b6772..5c5648f9d 100644
--- a/src/main/java/org/apache/datasketches/tuple/SummaryFactory.java
+++ b/src/main/java/org/apache/datasketches/tuple/SummaryFactory.java
@@ -26,6 +26,7 @@
 public interface SummaryFactory<S extends Summary> {
 
   /**
+   * Returns new instance of Summary
    * @return new instance of Summary
    */
   public S newSummary();
diff --git a/src/main/java/org/apache/datasketches/tuple/Util.java b/src/main/java/org/apache/datasketches/tuple/Util.java
index 88fef2602..92193ca56 100644
--- a/src/main/java/org/apache/datasketches/tuple/Util.java
+++ b/src/main/java/org/apache/datasketches/tuple/Util.java
@@ -119,16 +119,18 @@ public static String stringConcat(final String[] strArr) {
   }
 
   /**
+   * Returns the hash of the given string
    * @param s the string to hash
-   * @return the hash of the string
+   * @return the hash of the given string
    */
   public static long stringHash(final String s) {
     return hashString(s, 0, s.length(), PRIME);
   }
 
   /**
+   * Returns the hash of the concatenated strings
    * @param strArray array of Strings
-   * @return long hash of concatenated strings.
+   * @return the hash of concatenated strings.
    */
   public static long stringArrHash(final String[] strArray) {
     final String s = stringConcat(strArray);
diff --git a/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSketch.java b/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSketch.java
index d78f4e8b1..1bb9edeca 100644
--- a/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSketch.java
+++ b/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSketch.java
@@ -24,6 +24,7 @@
 import org.apache.datasketches.tuple.UpdatableSketch;
 
 /**
+ * Extends UpdatableSketch&lt;Double, DoubleSummary&gt;
  * @author Lee Rhodes
  */
 public class DoubleSketch extends UpdatableSketch<Double, DoubleSummary> {
diff --git a/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSummary.java b/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSummary.java
index a54c11afc..f678fba06 100644
--- a/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSummary.java
+++ b/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSummary.java
@@ -125,6 +125,7 @@ public DoubleSummary copy() {
   }
 
   /**
+   * Returns current value of the DoubleSummary
    * @return current value of the DoubleSummary
    */
   public double getValue() {
diff --git a/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSummaryDeserializer.java b/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSummaryDeserializer.java
index f8fae67a7..90e01b72b 100644
--- a/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSummaryDeserializer.java
+++ b/src/main/java/org/apache/datasketches/tuple/adouble/DoubleSummaryDeserializer.java
@@ -24,6 +24,7 @@
 import org.apache.datasketches.tuple.SummaryDeserializer;
 
 /**
+ * Implements SummaryDeserializer&lt;DoubleSummary&gt;
  * @author Lee Rhodes
  */
 public class DoubleSummaryDeserializer implements SummaryDeserializer<DoubleSummary> {
diff --git a/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSketch.java b/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSketch.java
index 438879824..0bad790cc 100644
--- a/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSketch.java
+++ b/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSketch.java
@@ -24,6 +24,7 @@
 import org.apache.datasketches.tuple.UpdatableSketch;
 
 /**
+ * Extends UpdatableSketch&lt;Integer, IntegerSummary&gt;
  * @author Lee Rhodes
  */
 public class IntegerSketch extends UpdatableSketch<Integer, IntegerSummary> {
diff --git a/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSummary.java b/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSummary.java
index 72695355e..a8cfdab56 100644
--- a/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSummary.java
+++ b/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSummary.java
@@ -125,6 +125,7 @@ public IntegerSummary copy() {
   }
 
   /**
+   * Returns the current value of the IntegerSummary
    * @return current value of the IntegerSummary
    */
   public int getValue() {
diff --git a/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSummaryDeserializer.java b/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSummaryDeserializer.java
index 0a4529e07..68d468785 100644
--- a/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSummaryDeserializer.java
+++ b/src/main/java/org/apache/datasketches/tuple/aninteger/IntegerSummaryDeserializer.java
@@ -24,6 +24,7 @@
 import org.apache.datasketches.tuple.SummaryDeserializer;
 
 /**
+ * Implements SummaryDeserializer&lt;IntegerSummary&gt;
  * @author Lee Rhodes
  */
 public class IntegerSummaryDeserializer implements SummaryDeserializer<IntegerSummary> {
diff --git a/src/main/java/org/apache/datasketches/tuple/arrayofdoubles/ArrayOfDoublesSketch.java b/src/main/java/org/apache/datasketches/tuple/arrayofdoubles/ArrayOfDoublesSketch.java
index 9453c872d..111427b7c 100644
--- a/src/main/java/org/apache/datasketches/tuple/arrayofdoubles/ArrayOfDoublesSketch.java
+++ b/src/main/java/org/apache/datasketches/tuple/arrayofdoubles/ArrayOfDoublesSketch.java
@@ -172,6 +172,7 @@ public boolean isEmpty() {
   }
 
   /**
+   * Returns number of double values associated with each key
    * @return number of double values associated with each key
    */
   public int getNumValues() {
@@ -196,11 +197,13 @@ public double getTheta() {
   }
 
   /**
+   * Returns number of retained entries
    * @return number of retained entries
    */
   public abstract int getRetainedEntries();
 
   /**
+   * Returns the maximum number of bytes for this sketch when serialized.
    * @return the maximum number of bytes for this sketch when serialized.
    */
   public abstract int getMaxBytes();
@@ -212,11 +215,13 @@ public double getTheta() {
   public abstract int getCurrentBytes();
 
   /**
+   * Returns serialized representation of the sketch
    * @return serialized representation of the sketch
    */
   public abstract byte[] toByteArray();
 
   /**
+   * Returns array of arrays of double values in the sketch
    * @return array of arrays of double values in the sketch
    */
   public abstract double[][] getValues();
@@ -226,6 +231,7 @@ public double getTheta() {
   abstract long[] getKeys();
 
   /**
+   * Returns the value of theta as a long
    * @return the value of theta as a long
    */
   long getThetaLong() {
@@ -235,11 +241,13 @@ long getThetaLong() {
   abstract short getSeedHash();
 
   /**
-   * @return iterator over the sketch
+   * Returns an iterator over the sketch
+   * @return an iterator over the sketch
    */
   public abstract ArrayOfDoublesSketchIterator iterator();
 
   /**
+   * Returns this sketch in compact form, which is immutable.
    * @return this sketch in compact form, which is immutable.
    */
   public ArrayOfDoublesCompactSketch compact() {
@@ -247,7 +255,7 @@ public ArrayOfDoublesCompactSketch compact() {
   }
 
   /**
-   *
+   * Returns this sketch in compact form, which is immutable.
    * @param dstMem the destination WritableMemory
    * @return this sketch in compact form, which is immutable.
    */
diff --git a/src/main/java/org/apache/datasketches/tuple/arrayofdoubles/ArrayOfDoublesUnion.java b/src/main/java/org/apache/datasketches/tuple/arrayofdoubles/ArrayOfDoublesUnion.java
index 599418f75..9e1db0ada 100644
--- a/src/main/java/org/apache/datasketches/tuple/arrayofdoubles/ArrayOfDoublesUnion.java
+++ b/src/main/java/org/apache/datasketches/tuple/arrayofdoubles/ArrayOfDoublesUnion.java
@@ -189,6 +189,7 @@ public void reset() {
   //      ||   15   |   14   |   13   |   12   |   11    |   10   |    9   |     8              |
   //  1   ||---------------------------Union Theta Long-----------------------------------------|
   /**
+   * Returns a byte array representation of this object
    * @return a byte array representation of this object
    */
   public byte[] toByteArray() {
@@ -206,6 +207,7 @@ public byte[] toByteArray() {
   }
 
   /**
+   * Returns maximum required storage bytes given nomEntries and numValues
    * @param nomEntries Nominal number of entries. Forced to the nearest power of 2 greater than or equal to
    * given value.
    * @param numValues Number of double values to keep for each key
diff --git a/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSketch.java b/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSketch.java
index c66802f06..99ddeee16 100644
--- a/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSketch.java
+++ b/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSketch.java
@@ -26,6 +26,7 @@
 import org.apache.datasketches.tuple.UpdatableSketch;
 
 /**
+ * Extends UpdatableSketch&lt;String[], ArrayOfStringsSummary&gt;
  * @author Lee Rhodes
  */
 public class ArrayOfStringsSketch extends UpdatableSketch<String[], ArrayOfStringsSummary> {
diff --git a/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummary.java b/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummary.java
index 69ee83e8e..48b2d6d6a 100644
--- a/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummary.java
+++ b/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummary.java
@@ -31,6 +31,7 @@
 import org.apache.datasketches.tuple.UpdatableSummary;
 
 /**
+ * Implements UpdatableSummary&lt;String[]&gt;
  * @author Lee Rhodes
  */
 public final class ArrayOfStringsSummary implements UpdatableSummary<String[]> {
@@ -115,6 +116,7 @@ public boolean equals(final Object summary) {
   }
 
   /**
+   * Returns the nodes array for this summary.
    * @return the nodes array for this summary.
    */
   public String[] getValue() {
diff --git a/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummaryDeserializer.java b/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummaryDeserializer.java
index 1fb47db1a..16467f338 100644
--- a/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummaryDeserializer.java
+++ b/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummaryDeserializer.java
@@ -24,6 +24,7 @@
 import org.apache.datasketches.tuple.SummaryDeserializer;
 
 /**
+ * Implements SummaryDeserializer&lt;ArrayOfStringsSummary&gt;
  * @author Lee Rhodes
  */
 public class ArrayOfStringsSummaryDeserializer implements SummaryDeserializer<ArrayOfStringsSummary> {
diff --git a/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummaryFactory.java b/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummaryFactory.java
index 8294b2bae..98fb7fb58 100644
--- a/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummaryFactory.java
+++ b/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummaryFactory.java
@@ -22,6 +22,7 @@
 import org.apache.datasketches.tuple.SummaryFactory;
 
 /**
+ * Implements SummaryFactory&lt;ArrayOfStringsSummary&gt;
  * @author Lee Rhodes
  */
 public class ArrayOfStringsSummaryFactory implements SummaryFactory<ArrayOfStringsSummary> {
diff --git a/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummarySetOperations.java b/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummarySetOperations.java
index dd24eabaa..2650b84ae 100644
--- a/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummarySetOperations.java
+++ b/src/main/java/org/apache/datasketches/tuple/strings/ArrayOfStringsSummarySetOperations.java
@@ -22,6 +22,7 @@
 import org.apache.datasketches.tuple.SummarySetOperations;
 
 /**
+ * Implements SummarySetOperations&lt;ArrayOfStringsSummary&gt;
  * @author Lee Rhodes
  */
 public class ArrayOfStringsSummarySetOperations implements SummarySetOperations<ArrayOfStringsSummary> {