HBASE-20928 Rewrite calculation of midpoint in binarySearch functions to prevent overflow

HBASE-20928 Rewrite calculation of midpoint - addendum (Xu Cang)

Signed-off-by: tedyu <yuzhihong@gmail.com>

Conflicts:
	hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/RowIndexSeekerV1.java
	hbase-common/src/main/java/org/apache/hadoop/hbase/util/Bytes.java

Amending-Author: Andrew Purtell <apurtell@apache.org>

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/RowIndexSeekerV1.java

@@ -154,15 +154,13 @@ public class RowIndexSeekerV1 extends AbstractEncodedSeeker {
   private int binarySearch(Cell seekCell, boolean seekBefore) {
     int low = 0;
     int high = rowNumber - 1;
-    int mid = (low + high) >>> 1;
+    int mid = low + ((high - low) >> 1);
     int comp = 0;
     SimpleMutableByteRange row = new SimpleMutableByteRange();
     while (low <= high) {
-      mid = (low + high) >>> 1;
+      mid = low + ((high - low) >> 1);
       getRow(mid, row);
-      comp = comparator.compareRows(row.getBytes(), row.getOffset(),
+      comp = compareRows(row, seekCell);
-          row.getLength(), seekCell.getRowArray(), seekCell.getRowOffset(),
-          seekCell.getRowLength());
       if (comp < 0) {
         low = mid + 1;
       } else if (comp > 0) {
@@ -184,6 +182,12 @@ public class RowIndexSeekerV1 extends AbstractEncodedSeeker {
     }
   }
 
+  private int compareRows(SimpleMutableByteRange row, Cell seekCell) {
+    return comparator.compareRows(row.getBytes(), row.getOffset(),
+      row.getLength(), seekCell.getRowArray(), seekCell.getRowOffset(),
+      seekCell.getRowLength());
+  }
+
   private void getRow(int index, SimpleMutableByteRange row) {
     int offset = Bytes.toIntUnsafe(rowOffsets.array(), rowOffsets.arrayOffset()
         + (index << 2)); // index * Bytes.SIZEOF_INT

hbase-common/src/main/java/org/apache/hadoop/hbase/util/Bytes.java

@@ -2145,7 +2145,7 @@ public class Bytes implements Comparable<Bytes> {
     int high = arr.length - 1;
 
     while (low <= high) {
-      int mid = (low+high) >>> 1;
+      int mid = low + ((high - low) >> 1);
       // we have to compare in this order, because the comparator order
       // has special logic when the 'left side' is a special key.
       int cmp = comparator.compare(key, offset, length,
@@ -2182,7 +2182,7 @@ public class Bytes implements Comparable<Bytes> {
     int high = arr.length - 1;
     KeyValue.KeyOnlyKeyValue r = new KeyValue.KeyOnlyKeyValue();
     while (low <= high) {
-      int mid = (low+high) >>> 1;
+      int mid = low + ((high - low) >> 1);
       // we have to compare in this order, because the comparator order
       // has special logic when the 'left side' is a special key.
       r.setKey(arr[mid], 0, arr[mid].length);
@@ -2357,7 +2357,7 @@ public class Bytes implements Comparable<Bytes> {
     int high = toIndex - 1;
 
     while (low <= high) {
-      int mid = (low + high) >>> 1;
+      int mid = low + ((high - low) >> 1);
       int midVal = a[mid] & 0xff;
 
       if (midVal < unsignedKey) {

hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileBlockIndex.java

@@ -533,7 +533,7 @@ public class HFileBlockIndex {
       // keys[low - 1] < key < keys[high + 1] while narrowing down the range.
       KeyValue.KeyOnlyKeyValue nonRootIndexKV = new KeyValue.KeyOnlyKeyValue();
       while (low <= high) {
-        mid = (low + high) >>> 1;
+        mid = low + ((high - low) >> 1);
 
         // Midkey's offset relative to the end of secondary index
         int midKeyRelOffset = nonRootIndex.getInt(

hbase-server/src/main/java/org/apache/hadoop/hbase/util/BoundedPriorityBlockingQueue.java

@@ -119,7 +119,7 @@ public class BoundedPriorityBlockingQueue<E> extends AbstractQueue<E> implements
 
     private int upperBound(int start, int end, E key) {
       while (start < end) {
-        int mid = (start + end) >>> 1;
+        int mid = start + ((end - start) >> 1);
         E mitem = objects[mid];
         int cmp = comparator.compare(mitem, key);
         if (cmp > 0) {