Allocate postings payload buffers only when the query requests them

Author: slow-J

lucene/CHANGES.txt

@@ -568,6 +568,8 @@ Optimizations
 
 * GITHUB#16228: Reuse scratch int[] for ordinal translation. (Tim Brooks)
 
+* GITHUB#16248: Allocate payload buffers in Lucene104PostingsReader only if payloads are requested. (Jakub Slowinski)
+
 Bug Fixes
 ---------------------
 * GITHUB#15754: Fix HTMLStripCharFilter to prevent tags from incorrectly consuming subsequent

lucene/core/src/java/org/apache/lucene/codecs/lucene104/Lucene104PostingsReader.java

@@ -476,7 +476,7 @@ public BlockPostingsEnum(FieldInfo fieldInfo, int flags, boolean needsImpacts)
         endOffset = -1;
       }
 
-      if (indexHasPayloads) {
+      if (needsPayloads) {
         payloadLengthBuffer = new int[BLOCK_SIZE];
         payloadBytes = new byte[128];
         payload = new BytesRef();
@@ -1180,12 +1180,12 @@ private void refillLastPositionBlock() throws IOException {
       for (int i = 0; i < count; i++) {
         int code = posIn.readVInt();
         if (indexHasPayloads) {
+          posDeltaBuffer[i] = code >>> 1;
           if ((code & 1) != 0) {
             payloadLength = posIn.readVInt();
           }
-          if (payloadLengthBuffer != null) { // needs payloads
+          if (needsPayloads) {
             payloadLengthBuffer[i] = payloadLength;
-            posDeltaBuffer[i] = code >>> 1;
             if (payloadLength != 0) {
               if (payloadByteUpto + payloadLength > payloadBytes.length) {
                 payloadBytes = ArrayUtil.grow(payloadBytes, payloadByteUpto + payloadLength);