Removing unnecessary ByteArrayDataInput allocations by resetting inplace (#14113)

Removing unnecessary ByteArrayDataInput allocations by resetting inplace

Signed-off-by: Ankit Jain <[email protected]>

Author: jainankitk

lucene/CHANGES.txt

@@ -52,6 +52,8 @@ Improvements
   (Robert Muir)
 * GITHUB#13984: Add HNSW graph checks and stats to CheckIndex
 
+* GITHUB#14113: Remove unnecessary ByteArrayDataInput allocations from `Lucene90DocValuesProducer$TermsDict.decompressBlock`. (Ankit Jain)
+
 Optimizations
 ---------------------
 

lucene/core/src/java/org/apache/lucene/codecs/lucene90/Lucene90DocValuesProducer.java

@@ -1122,10 +1122,9 @@ private class TermsDict extends BaseTermsEnum {
     final LongValues indexAddresses;
     final RandomAccessInput indexBytes;
     final BytesRef term;
+    final BytesRef blockBuffer;
+    final ByteArrayDataInput blockInput;
     long ord = -1;
-
-    BytesRef blockBuffer = null;
-    ByteArrayDataInput blockInput = null;
     long currentCompressedBlockStart = -1;
     long currentCompressedBlockEnd = -1;
 
@@ -1149,6 +1148,7 @@ private class TermsDict extends BaseTermsEnum {
       // add 7 padding bytes can help decompression run faster.
       int bufferSize = entry.maxBlockLength + entry.maxTermLength + LZ4_DECOMPRESSOR_PADDING;
       blockBuffer = new BytesRef(new byte[bufferSize], 0, bufferSize);
+      blockInput = new ByteArrayDataInput();
     }
 
     @Override
@@ -1324,8 +1324,7 @@ private void decompressBlock() throws IOException {
         }
 
         // Reset the buffer.
-        blockInput =
-            new ByteArrayDataInput(blockBuffer.bytes, blockBuffer.offset, blockBuffer.length);
+        blockInput.reset(blockBuffer.bytes, blockBuffer.offset, blockBuffer.length);
       }
     }