Remove IOContext from Directory#openChecksumInput (#12027)

lucene/CHANGES.txt

@@ -37,6 +37,8 @@ API Changes
 * GITHUB#11840: Query rewrite now takes an IndexSearcher instead of IndexReader to enable concurrent
   rewriting. (Patrick Zhai)
 
+* GITHUB#11933: Remove IOContext from Directory#openChecksumInput. (Zach Chen)
+
 * GITHUB#11814: Support deletions in IndexRearranger. (Stefan Vodita)
 
 New Features

lucene/MIGRATE.md

@@ -74,6 +74,12 @@ determine the number of valid ordinals for the currently-positioned document up-
 illegal to call `SortedSetDocValues#nextOrd()` more than `SortedSetDocValues#docValueCount()` times
 for the currently-positioned document (doing so will result in undefined behavior).
 
+### IOContext removed from Directory#openChecksumInput (GITHUB-12027)
+
+`Directory#openChecksumInput` no longer takes in `IOContext` as a parameter, and will always use value
+`IOContext.READONCE` for opening internally, as that's the only valid usage pattern for checksum input.
+Callers should remove the parameter when calling this method.
+
 ## Migration from Lucene 9.0 to Lucene 9.1
 
 ### Test framework package migration and module (LUCENE-10301)

lucene/analysis/common/src/java/org/apache/lucene/analysis/hunspell/Dictionary.java

@@ -1136,7 +1136,7 @@ private WordStorage readSortedDictionaries(
         new WordStorage.Builder(wordCount, hasCustomMorphData, flags, allNonSuggestibleFlags());
 
     try (ByteSequencesReader reader =
-        new ByteSequencesReader(tempDir.openChecksumInput(sorted, IOContext.READONCE), sorted)) {
+        new ByteSequencesReader(tempDir.openChecksumInput(sorted), sorted)) {
 
       // TODO: the flags themselves can be double-chars (long) or also numeric
       // either way the trick is to encode them as char... but they must be parsed differently

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene90/Lucene90FieldInfosFormat.java

@@ -122,7 +122,7 @@ public FieldInfos read(
       throws IOException {
     final String fileName =
         IndexFileNames.segmentFileName(segmentInfo.name, segmentSuffix, EXTENSION);
-    try (ChecksumIndexInput input = directory.openChecksumInput(fileName, context)) {
+    try (ChecksumIndexInput input = directory.openChecksumInput(fileName)) {
       Throwable priorE = null;
       FieldInfo[] infos = null;
       try {

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene90/Lucene90HnswVectorsReader.java

@@ -93,7 +93,7 @@ private int readMetadata(SegmentReadState state) throws IOException {
         IndexFileNames.segmentFileName(
             state.segmentInfo.name, state.segmentSuffix, Lucene90HnswVectorsFormat.META_EXTENSION);
     int versionMeta = -1;
-    try (ChecksumIndexInput meta = state.directory.openChecksumInput(metaFileName, state.context)) {
+    try (ChecksumIndexInput meta = state.directory.openChecksumInput(metaFileName)) {
       Throwable priorE = null;
       try {
         versionMeta =

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene91/Lucene91HnswVectorsReader.java

@@ -90,7 +90,7 @@ private int readMetadata(SegmentReadState state) throws IOException {
         IndexFileNames.segmentFileName(
             state.segmentInfo.name, state.segmentSuffix, Lucene91HnswVectorsFormat.META_EXTENSION);
     int versionMeta = -1;
-    try (ChecksumIndexInput meta = state.directory.openChecksumInput(metaFileName, state.context)) {
+    try (ChecksumIndexInput meta = state.directory.openChecksumInput(metaFileName)) {
       Throwable priorE = null;
       try {
         versionMeta =

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene92/Lucene92HnswVectorsReader.java

@@ -88,7 +88,7 @@ private int readMetadata(SegmentReadState state) throws IOException {
         IndexFileNames.segmentFileName(
             state.segmentInfo.name, state.segmentSuffix, Lucene92HnswVectorsFormat.META_EXTENSION);
     int versionMeta = -1;
-    try (ChecksumIndexInput meta = state.directory.openChecksumInput(metaFileName, state.context)) {
+    try (ChecksumIndexInput meta = state.directory.openChecksumInput(metaFileName)) {
       Throwable priorE = null;
       try {
         versionMeta =

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene94/Lucene94HnswVectorsReader.java

@@ -38,7 +38,6 @@
 import org.apache.lucene.search.TotalHits;
 import org.apache.lucene.store.ChecksumIndexInput;
 import org.apache.lucene.store.DataInput;
-import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.util.Bits;
 import org.apache.lucene.util.BytesRef;
@@ -89,8 +88,7 @@ private int readMetadata(SegmentReadState state) throws IOException {
         IndexFileNames.segmentFileName(
             state.segmentInfo.name, state.segmentSuffix, Lucene94HnswVectorsFormat.META_EXTENSION);
     int versionMeta = -1;
-    try (ChecksumIndexInput meta =
-        state.directory.openChecksumInput(metaFileName, IOContext.READONCE)) {
+    try (ChecksumIndexInput meta = state.directory.openChecksumInput(metaFileName)) {
       Throwable priorE = null;
       try {
         versionMeta =

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/store/EndiannessReverserUtil.java

@@ -45,7 +45,7 @@ public static IndexInput openInput(Directory directory, String name, IOContext c
   /** Open a checksum index input */
   public static ChecksumIndexInput openChecksumInput(
       Directory directory, String name, IOContext context) throws IOException {
-    return new EndiannessReverserChecksumIndexInput(directory.openChecksumInput(name, context));
+    return new EndiannessReverserChecksumIndexInput(directory.openChecksumInput(name));
   }
 
   /** Open an index output */

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene60/bkd/BKDWriter60.java

@@ -32,7 +32,6 @@
 import org.apache.lucene.store.ChecksumIndexInput;
 import org.apache.lucene.store.DataOutput;
 import org.apache.lucene.store.Directory;
-import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexOutput;
 import org.apache.lucene.store.TrackingDirectoryWrapper;
 import org.apache.lucene.util.ArrayUtil;
@@ -1577,7 +1576,7 @@ private Error verifyChecksum(Throwable priorException, PointWriter writer) throw
       // We are reading from a temp file; go verify the checksum:
       String tempFileName = ((OfflinePointWriter) writer).name;
       if (tempDir.getCreatedFiles().contains(tempFileName)) {
-        try (ChecksumIndexInput in = tempDir.openChecksumInput(tempFileName, IOContext.READONCE)) {
+        try (ChecksumIndexInput in = tempDir.openChecksumInput(tempFileName)) {
           CodecUtil.checkFooter(in, priorException);
         }
       }

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/store/TestEndiannessReverserCheckSumIndexInput.java

@@ -29,7 +29,7 @@ public class TestEndiannessReverserCheckSumIndexInput extends EndiannessReverser
   @Override
   protected IndexInput getEndiannessReverserInput(Directory dir, String name, IOContext context)
       throws IOException {
-    return new EndiannessReverserChecksumIndexInput(dir.openChecksumInput(name, context));
+    return new EndiannessReverserChecksumIndexInput(dir.openChecksumInput(name));
   }
 
   @Override

lucene/codecs/src/java/org/apache/lucene/codecs/bloom/BloomFilteringPostingsFormat.java

@@ -152,7 +152,7 @@ public BloomFilteredFieldsProducer(SegmentReadState state) throws IOException {
       ChecksumIndexInput bloomIn = null;
       boolean success = false;
       try {
-        bloomIn = state.directory.openChecksumInput(bloomFileName, state.context);
+        bloomIn = state.directory.openChecksumInput(bloomFileName);
         CodecUtil.checkIndexHeader(
             bloomIn,
             BLOOM_CODEC_NAME,

lucene/codecs/src/java/org/apache/lucene/codecs/simpletext/SimpleTextBKDWriter.java

@@ -45,7 +45,6 @@
 import org.apache.lucene.index.PointValues.Relation;
 import org.apache.lucene.store.ChecksumIndexInput;
 import org.apache.lucene.store.Directory;
-import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexOutput;
 import org.apache.lucene.store.TrackingDirectoryWrapper;
 import org.apache.lucene.util.ArrayUtil;
@@ -841,7 +840,7 @@ private Error verifyChecksum(Throwable priorException, PointWriter writer) throw
     if (writer instanceof OfflinePointWriter) {
       // We are reading from a temp file; go verify the checksum:
       String tempFileName = ((OfflinePointWriter) writer).name;
-      try (ChecksumIndexInput in = tempDir.openChecksumInput(tempFileName, IOContext.READONCE)) {
+      try (ChecksumIndexInput in = tempDir.openChecksumInput(tempFileName)) {
         CodecUtil.checkFooter(in, priorException);
       }
     }

lucene/codecs/src/java/org/apache/lucene/codecs/simpletext/SimpleTextFieldInfosFormat.java

@@ -79,7 +79,7 @@ public FieldInfos read(
       throws IOException {
     final String fileName =
         IndexFileNames.segmentFileName(segmentInfo.name, segmentSuffix, FIELD_INFOS_EXTENSION);
-    ChecksumIndexInput input = directory.openChecksumInput(fileName, iocontext);
+    ChecksumIndexInput input = directory.openChecksumInput(fileName);
     BytesRefBuilder scratch = new BytesRefBuilder();
 
     boolean success = false;

lucene/codecs/src/java/org/apache/lucene/codecs/simpletext/SimpleTextKnnVectorsReader.java

@@ -82,8 +82,7 @@ public class SimpleTextKnnVectorsReader extends KnnVectorsReader {
             SimpleTextKnnVectorsFormat.VECTOR_EXTENSION);
 
     boolean success = false;
-    try (ChecksumIndexInput in =
-        readState.directory.openChecksumInput(metaFileName, IOContext.DEFAULT)) {
+    try (ChecksumIndexInput in = readState.directory.openChecksumInput(metaFileName)) {
       int fieldNumber = readInt(in, FIELD_NUMBER);
       while (fieldNumber != -1) {
         String fieldName = readString(in, FIELD_NAME);

lucene/codecs/src/java/org/apache/lucene/codecs/simpletext/SimpleTextLiveDocsFormat.java

@@ -61,7 +61,7 @@ public Bits readLiveDocs(Directory dir, SegmentCommitInfo info, IOContext contex
     ChecksumIndexInput in = null;
     boolean success = false;
     try {
-      in = dir.openChecksumInput(fileName, context);
+      in = dir.openChecksumInput(fileName);
 
       SimpleTextUtil.readLine(in, scratch);
       assert StringHelper.startsWith(scratch.get(), SIZE);

lucene/codecs/src/java/org/apache/lucene/codecs/simpletext/SimpleTextPointsReader.java

@@ -70,8 +70,7 @@ public SimpleTextPointsReader(SegmentReadState readState) throws IOException {
             readState.segmentInfo.name,
             readState.segmentSuffix,
             SimpleTextPointsFormat.POINT_INDEX_EXTENSION);
-    try (ChecksumIndexInput in =
-        readState.directory.openChecksumInput(indexFileName, IOContext.DEFAULT)) {
+    try (ChecksumIndexInput in = readState.directory.openChecksumInput(indexFileName)) {
       readLine(in);
       int count = parseInt(FIELD_COUNT);
       for (int i = 0; i < count; i++) {

lucene/codecs/src/java/org/apache/lucene/codecs/simpletext/SimpleTextSegmentInfoFormat.java

@@ -78,7 +78,7 @@ public SegmentInfo read(
     BytesRefBuilder scratch = new BytesRefBuilder();
     String segFileName =
         IndexFileNames.segmentFileName(segmentName, "", SimpleTextSegmentInfoFormat.SI_EXTENSION);
-    try (ChecksumIndexInput input = directory.openChecksumInput(segFileName, context)) {
+    try (ChecksumIndexInput input = directory.openChecksumInput(segFileName)) {
       SimpleTextUtil.readLine(input, scratch);
       assert StringHelper.startsWith(scratch.get(), SI_VERSION);
       final Version version;

lucene/core/src/java/org/apache/lucene/codecs/lucene90/Lucene90CompoundFormat.java

@@ -110,7 +110,7 @@ private void writeCompoundFile(
       // align file start offset
       long startOffset = data.alignFilePointer(Long.BYTES);
       // write bytes for file
-      try (ChecksumIndexInput in = dir.openChecksumInput(file, IOContext.READONCE)) {
+      try (ChecksumIndexInput in = dir.openChecksumInput(file)) {
 
         // just copies the index header, verifying that its id matches what we expect
         CodecUtil.verifyAndCopyIndexHeader(in, data, si.getId());

lucene/core/src/java/org/apache/lucene/codecs/lucene90/Lucene90CompoundReader.java

@@ -106,8 +106,7 @@ public Lucene90CompoundReader(Directory directory, SegmentInfo si, IOContext con
   private Map<String, FileEntry> readEntries(
       byte[] segmentID, Directory dir, String entriesFileName) throws IOException {
     Map<String, FileEntry> mapping = null;
-    try (ChecksumIndexInput entriesStream =
-        dir.openChecksumInput(entriesFileName, IOContext.READONCE)) {
+    try (ChecksumIndexInput entriesStream = dir.openChecksumInput(entriesFileName)) {
       Throwable priorE = null;
       try {
         version =

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

@@ -42,7 +42,6 @@
 import org.apache.lucene.store.ByteArrayDataInput;
 import org.apache.lucene.store.ChecksumIndexInput;
 import org.apache.lucene.store.DataInput;
-import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.RandomAccessInput;
 import org.apache.lucene.util.BytesRef;
@@ -83,7 +82,7 @@ final class Lucene90DocValuesProducer extends DocValuesProducer {
     merging = false;
 
     // read in the entries from the metadata file.
-    try (ChecksumIndexInput in = state.directory.openChecksumInput(metaName, IOContext.READONCE)) {
+    try (ChecksumIndexInput in = state.directory.openChecksumInput(metaName)) {
       Throwable priorE = null;
 
       try {

lucene/core/src/java/org/apache/lucene/codecs/lucene90/Lucene90LiveDocsFormat.java

@@ -68,7 +68,7 @@ public Bits readLiveDocs(Directory dir, SegmentCommitInfo info, IOContext contex
     long gen = info.getDelGen();
     String name = IndexFileNames.fileNameFromGeneration(info.info.name, EXTENSION, gen);
     final int length = info.info.maxDoc();
-    try (ChecksumIndexInput input = dir.openChecksumInput(name, context)) {
+    try (ChecksumIndexInput input = dir.openChecksumInput(name)) {
       Throwable priorE = null;
       try {
         CodecUtil.checkIndexHeader(

lucene/core/src/java/org/apache/lucene/codecs/lucene90/Lucene90NormsProducer.java

@@ -32,7 +32,6 @@
 import org.apache.lucene.index.NumericDocValues;
 import org.apache.lucene.index.SegmentReadState;
 import org.apache.lucene.store.ChecksumIndexInput;
-import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.RandomAccessInput;
 import org.apache.lucene.util.IOUtils;
@@ -61,7 +60,7 @@ final class Lucene90NormsProducer extends NormsProducer implements Cloneable {
     int version = -1;
 
     // read in the entries from the metadata file.
-    try (ChecksumIndexInput in = state.directory.openChecksumInput(metaName, IOContext.READONCE)) {
+    try (ChecksumIndexInput in = state.directory.openChecksumInput(metaName)) {
       Throwable priorE = null;
       try {
         version =

lucene/core/src/java/org/apache/lucene/codecs/lucene90/Lucene90PointsReader.java

@@ -81,8 +81,7 @@ public Lucene90PointsReader(SegmentReadState readState) throws IOException {
       CodecUtil.retrieveChecksum(dataIn);
 
       long indexLength = -1, dataLength = -1;
-      try (ChecksumIndexInput metaIn =
-          readState.directory.openChecksumInput(metaFileName, IOContext.READONCE)) {
+      try (ChecksumIndexInput metaIn = readState.directory.openChecksumInput(metaFileName)) {
         Throwable priorE = null;
         try {
           CodecUtil.checkIndexHeader(

lucene/core/src/java/org/apache/lucene/codecs/lucene90/Lucene90SegmentInfoFormat.java

@@ -99,7 +99,7 @@ public Lucene90SegmentInfoFormat() {}
   public SegmentInfo read(Directory dir, String segment, byte[] segmentID, IOContext context)
       throws IOException {
     final String fileName = IndexFileNames.segmentFileName(segment, "", SI_EXTENSION);
-    try (ChecksumIndexInput input = dir.openChecksumInput(fileName, context)) {
+    try (ChecksumIndexInput input = dir.openChecksumInput(fileName)) {
       Throwable priorE = null;
       SegmentInfo si = null;
       try {

lucene/core/src/java/org/apache/lucene/codecs/lucene90/blocktree/Lucene90BlockTreeTermsReader.java

@@ -150,8 +150,7 @@ public Lucene90BlockTreeTermsReader(PostingsReaderBase postingsReader, SegmentRe
       Map<String, FieldReader> fieldMap = null;
       Throwable priorE = null;
       long indexLength = -1, termsLength = -1;
-      try (ChecksumIndexInput metaIn =
-          state.directory.openChecksumInput(metaName, IOContext.READONCE)) {
+      try (ChecksumIndexInput metaIn = state.directory.openChecksumInput(metaName)) {
         try {
           CodecUtil.checkIndexHeader(
               metaIn,

lucene/core/src/java/org/apache/lucene/codecs/lucene90/compressing/FieldsIndexWriter.java

@@ -120,8 +120,7 @@ void finish(int numDocs, long maxPointer, IndexOutput metaOut) throws IOExceptio
       metaOut.writeInt(totalChunks + 1);
       metaOut.writeLong(dataOut.getFilePointer());
 
-      try (ChecksumIndexInput docsIn =
-          dir.openChecksumInput(docsOut.getName(), IOContext.READONCE)) {
+      try (ChecksumIndexInput docsIn = dir.openChecksumInput(docsOut.getName())) {
         CodecUtil.checkHeader(docsIn, codecName + "Docs", VERSION_CURRENT, VERSION_CURRENT);
         Throwable priorE = null;
         try {
@@ -147,8 +146,7 @@ void finish(int numDocs, long maxPointer, IndexOutput metaOut) throws IOExceptio
       docsOut = null;
 
       metaOut.writeLong(dataOut.getFilePointer());
-      try (ChecksumIndexInput filePointersIn =
-          dir.openChecksumInput(filePointersOut.getName(), IOContext.READONCE)) {
+      try (ChecksumIndexInput filePointersIn = dir.openChecksumInput(filePointersOut.getName())) {
         CodecUtil.checkHeader(
             filePointersIn, codecName + "FilePointers", VERSION_CURRENT, VERSION_CURRENT);
         Throwable priorE = null;

lucene/core/src/java/org/apache/lucene/codecs/lucene90/compressing/Lucene90CompressingStoredFieldsReader.java

@@ -137,7 +137,7 @@ public Lucene90CompressingStoredFieldsReader(
 
       final String metaStreamFN =
           IndexFileNames.segmentFileName(segment, segmentSuffix, META_EXTENSION);
-      metaIn = d.openChecksumInput(metaStreamFN, IOContext.READONCE);
+      metaIn = d.openChecksumInput(metaStreamFN);
       CodecUtil.checkIndexHeader(
           metaIn,
           INDEX_CODEC_NAME + "Meta",

lucene/core/src/java/org/apache/lucene/codecs/lucene90/compressing/Lucene90CompressingTermVectorsReader.java

@@ -143,7 +143,7 @@ public Lucene90CompressingTermVectorsReader(
 
       final String metaStreamFN =
           IndexFileNames.segmentFileName(segment, segmentSuffix, VECTORS_META_EXTENSION);
-      metaIn = d.openChecksumInput(metaStreamFN, IOContext.READONCE);
+      metaIn = d.openChecksumInput(metaStreamFN);
       CodecUtil.checkIndexHeader(
           metaIn,
           VECTORS_INDEX_CODEC_NAME + "Meta",

lucene/core/src/java/org/apache/lucene/codecs/lucene94/Lucene94FieldInfosFormat.java

@@ -127,7 +127,7 @@ public FieldInfos read(
       throws IOException {
     final String fileName =
         IndexFileNames.segmentFileName(segmentInfo.name, segmentSuffix, EXTENSION);
-    try (ChecksumIndexInput input = directory.openChecksumInput(fileName, context)) {
+    try (ChecksumIndexInput input = directory.openChecksumInput(fileName)) {
       Throwable priorE = null;
       FieldInfo[] infos = null;
       try {

lucene/core/src/java/org/apache/lucene/codecs/lucene95/Lucene95HnswVectorsReader.java

@@ -38,7 +38,6 @@
 import org.apache.lucene.search.TotalHits;
 import org.apache.lucene.store.ChecksumIndexInput;
 import org.apache.lucene.store.DataInput;
-import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.RandomAccessInput;
 import org.apache.lucene.util.Accountable;
@@ -96,8 +95,7 @@ private int readMetadata(SegmentReadState state) throws IOException {
         IndexFileNames.segmentFileName(
             state.segmentInfo.name, state.segmentSuffix, Lucene95HnswVectorsFormat.META_EXTENSION);
     int versionMeta = -1;
-    try (ChecksumIndexInput meta =
-        state.directory.openChecksumInput(metaFileName, IOContext.READONCE)) {
+    try (ChecksumIndexInput meta = state.directory.openChecksumInput(metaFileName)) {
       Throwable priorE = null;
       try {
         versionMeta =

lucene/core/src/java/org/apache/lucene/index/SegmentInfos.java

@@ -288,7 +288,7 @@ static final SegmentInfos readCommit(
 
     long generation = generationFromSegmentsFileName(segmentFileName);
     // System.out.println(Thread.currentThread() + ": SegmentInfos.readCommit " + segmentFileName);
-    try (ChecksumIndexInput input = directory.openChecksumInput(segmentFileName, IOContext.READ)) {
+    try (ChecksumIndexInput input = directory.openChecksumInput(segmentFileName)) {
       try {
         return readCommit(directory, input, generation, minSupportedMajorVersion);
       } catch (EOFException | NoSuchFileException | FileNotFoundException e) {

lucene/core/src/java/org/apache/lucene/store/Directory.java

@@ -152,8 +152,8 @@ public abstract IndexOutput createTempOutput(String prefix, String suffix, IOCon
    * @param name the name of an existing file.
    * @throws IOException in case of I/O error
    */
-  public ChecksumIndexInput openChecksumInput(String name, IOContext context) throws IOException {
-    return new BufferedChecksumIndexInput(openInput(name, context));
+  public ChecksumIndexInput openChecksumInput(String name) throws IOException {
+    return new BufferedChecksumIndexInput(openInput(name, IOContext.READONCE));
   }
 
   /**

lucene/core/src/java/org/apache/lucene/util/OfflineSorter.java

@@ -283,8 +283,7 @@ public String sort(String inputFileName) throws IOException {
     TrackingDirectoryWrapper trackingDir = new TrackingDirectoryWrapper(dir);
 
     boolean success = false;
-    try (ByteSequencesReader is =
-        getReader(dir.openChecksumInput(inputFileName, IOContext.READONCE), inputFileName)) {
+    try (ByteSequencesReader is = getReader(dir.openChecksumInput(inputFileName), inputFileName)) {
       while (true) {
         Partition part = readPartition(is);
         if (part.count == 0) {
@@ -367,7 +366,7 @@ public String sort(String inputFileName) throws IOException {
    */
   private void verifyChecksum(Throwable priorException, ByteSequencesReader reader)
       throws IOException {
-    try (ChecksumIndexInput in = dir.openChecksumInput(reader.name, IOContext.READONCE)) {
+    try (ChecksumIndexInput in = dir.openChecksumInput(reader.name)) {
       CodecUtil.checkFooter(in, priorException);
     }
   }
@@ -701,9 +700,7 @@ protected boolean lessThan(FileAndTop a, FileAndTop b) {
         // Open streams and read the top for each file
         for (int i = 0; i < segmentsToMerge.size(); i++) {
           Partition segment = getPartition(segmentsToMerge.get(i));
-          streams[i] =
-              getReader(
-                  dir.openChecksumInput(segment.fileName, IOContext.READONCE), segment.fileName);
+          streams[i] = getReader(dir.openChecksumInput(segment.fileName), segment.fileName);
 
           BytesRef item = null;
           try {