minor cleanups.

src/main/java/org/apache/datasketches/filters/bloomfilter/BitArray.java

@@ -27,13 +27,13 @@
 
 /**
  * This class holds an array of bits suitable for use in a Bloom Filter
- * 
+ *
  * <p>Rounds the number of bits up to the smallest multiple of 64 (one long)
  * that is not smaller than the specified number.
  */
 final class BitArray {
   // MAX_BITS using longs, based on array indices being capped at Integer.MAX_VALUE
-  private static final long MAX_BITS = Integer.MAX_VALUE * (long) Long.SIZE; 
+  private static final long MAX_BITS = Integer.MAX_VALUE * (long) Long.SIZE;
 
   private long numBitsSet_;  // if -1, need to recompute value
   private boolean isDirty_;
@@ -68,10 +68,10 @@ static BitArray heapify(final Buffer buffer, final boolean isEmpty) {
     if (numLongs < 0) {
       throw new SketchesArgumentException("Possible corruption: Must have strictly positive array size. Found: " + numLongs);
     }
-    
+
     if (isEmpty) {
       return new BitArray((long) numLongs * Long.SIZE);
-    }    
+    }
 
     buffer.getInt(); // unused
 
@@ -120,7 +120,7 @@ long getNumBitsSet() {
       numBitsSet_ = 0;
       for (final long val : data_) {
         numBitsSet_ += Long.bitCount(val);
-      }  
+      }
     }
     return numBitsSet_;
   }
@@ -184,7 +184,7 @@ long getSerializedSizeBytes() {
   void writeToBuffer(final WritableBuffer wbuf) {
     wbuf.putInt(data_.length);
     wbuf.putInt(0); // unused
-    
+
     if (!isEmpty()) {
       wbuf.putLong(isDirty_ ? -1 : numBitsSet_);
       wbuf.putLongArray(data_, 0, data_.length);
@@ -204,7 +204,7 @@ public String toString() {
   }
 
   // prints a long as a series of 0s and 1s as little endian
-  private String printLong(final long val) {
+  private static String printLong(final long val) {
     final StringBuilder sb = new StringBuilder();
     for (int j = 0; j < Long.SIZE; ++j) {
       sb.append((val & (1L << j)) != 0 ? "1" : "0");

src/main/java/org/apache/datasketches/filters/bloomfilter/BloomFilterBuilder.java

@@ -26,7 +26,7 @@
 /**
  * <p>This class provides methods to help estimate the correct paramters to use when
  * creating a Bloom filter, and methods to create the filter using those values.</p>
- * 
+ *
  * <p>The underlying math is described in the
  * <a href='https://en.wikipedia.org/wiki/Bloom_filter#Optimal_number_of_hash_functions'>
  * Wikipedia article on Bloom filters</a>.</p>
@@ -75,7 +75,7 @@ public static long suggestNumFilterBits(final long maxDistinctItems, final doubl
     if (targetFalsePositiveProb <= 0.0 || targetFalsePositiveProb > 1.0) {
       throw new SketchesArgumentException("targetFalsePositiveProb must be a valid probability and strictly greater than 0");
     }
-    return (long) Math.round(-maxDistinctItems * Math.log(targetFalsePositiveProb) / (Math.log(2) * Math.log(2)));
+    return Math.round(-maxDistinctItems * Math.log(targetFalsePositiveProb) / (Math.log(2) * Math.log(2)));
   }
 
   /**
@@ -93,7 +93,7 @@ public static BloomFilter createByAccuracy(final long maxDistinctItems, final do
    * using the provided base seed for the hash function.
    * @param maxDistinctItems The maximum expected number of distinct items to add to the filter
    * @param targetFalsePositiveProb A desired false positive probability per item
-   * @param seed A base hash seed 
+   * @param seed A base hash seed
    * @return A new BloomFilter configured for the given input parameters
    */
   public static BloomFilter createByAccuracy(final long maxDistinctItems, final double targetFalsePositiveProb, final long seed) {

src/main/java/org/apache/datasketches/filters/bloomfilter/package-info.java

@@ -0,0 +1,20 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.apache.datasketches.filters.bloomfilter;