Index: lucene/core/src/java/org/apache/lucene/codecs/compressing/CompressingTermVectorsReader.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/codecs/compressing/CompressingTermVectorsReader.java	(revision 1491444)
+++ lucene/core/src/java/org/apache/lucene/codecs/compressing/CompressingTermVectorsReader.java	(working copy)
@@ -102,20 +102,23 @@
     numDocs = si.getDocCount();
     IndexInput indexStream = null;
     try {
-      vectorsStream = d.openInput(IndexFileNames.segmentFileName(segment, segmentSuffix, VECTORS_EXTENSION), context);
+      // Load the index into memory
       final String indexStreamFN = IndexFileNames.segmentFileName(segment, segmentSuffix, VECTORS_INDEX_EXTENSION);
       indexStream = d.openInput(indexStreamFN, context);
-
       final String codecNameIdx = formatName + CODEC_SFX_IDX;
-      final String codecNameDat = formatName + CODEC_SFX_DAT;
       CodecUtil.checkHeader(indexStream, codecNameIdx, VERSION_START, VERSION_CURRENT);
-      CodecUtil.checkHeader(vectorsStream, codecNameDat, VERSION_START, VERSION_CURRENT);
-      assert CodecUtil.headerLength(codecNameDat) == vectorsStream.getFilePointer();
       assert CodecUtil.headerLength(codecNameIdx) == indexStream.getFilePointer();
-
       indexReader = new CompressingStoredFieldsIndexReader(indexStream, si);
+      indexStream.close();
       indexStream = null;
 
+      // Open the data file and read metadata
+      final String vectorsStreamFN = IndexFileNames.segmentFileName(segment, segmentSuffix, VECTORS_EXTENSION);
+      vectorsStream = d.openInput(vectorsStreamFN, context);
+      final String codecNameDat = formatName + CODEC_SFX_DAT;
+      CodecUtil.checkHeader(vectorsStream, codecNameDat, VERSION_START, VERSION_CURRENT);
+      assert CodecUtil.headerLength(codecNameDat) == vectorsStream.getFilePointer();
+
       packedIntsVersion = vectorsStream.readVInt();
       chunkSize = vectorsStream.readVInt();
       decompressor = compressionMode.newDecompressor();
@@ -161,7 +164,7 @@
   @Override
   public void close() throws IOException {
     if (!closed) {
-      IOUtils.close(vectorsStream, indexReader);
+      IOUtils.close(vectorsStream);
       closed = true;
     }
   }
Index: lucene/core/src/java/org/apache/lucene/codecs/compressing/CompressingStoredFieldsIndexReader.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/codecs/compressing/CompressingStoredFieldsIndexReader.java	(revision 1491444)
+++ lucene/core/src/java/org/apache/lucene/codecs/compressing/CompressingStoredFieldsIndexReader.java	(working copy)
@@ -17,7 +17,6 @@
  * limitations under the License.
  */
 
-import java.io.Closeable;
 import java.io.IOException;
 import java.util.Arrays;
 
@@ -25,17 +24,14 @@
 import org.apache.lucene.index.SegmentInfo;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.util.ArrayUtil;
-import org.apache.lucene.util.IOUtils;
 import org.apache.lucene.util.packed.PackedInts;
 
 /**
  * Random-access reader for {@link CompressingStoredFieldsIndexWriter}.
  * @lucene.internal
  */
-public final class CompressingStoredFieldsIndexReader implements Closeable, Cloneable {
+public final class CompressingStoredFieldsIndexReader implements Cloneable {
 
-  final IndexInput fieldsIndexIn;
-
   static long moveLowOrderBitToSign(long n) {
     return ((n >>> 1) ^ -(n & 1));
   }
@@ -48,8 +44,9 @@
   final PackedInts.Reader[] docBasesDeltas; // delta from the avg
   final PackedInts.Reader[] startPointersDeltas; // delta from the avg
 
+  // It is the responsibility of the caller to close fieldsIndexIn after this constructor
+  // has been called
   CompressingStoredFieldsIndexReader(IndexInput fieldsIndexIn, SegmentInfo si) throws IOException {
-    this.fieldsIndexIn = fieldsIndexIn;
     maxDoc = si.getDocCount();
     int[] docBases = new int[16];
     long[] startPointers = new long[16];
@@ -106,17 +103,6 @@
     this.startPointersDeltas = Arrays.copyOf(startPointersDeltas, blockCount);
   }
 
-  private CompressingStoredFieldsIndexReader(CompressingStoredFieldsIndexReader other) {
-    this.fieldsIndexIn = null;
-    this.maxDoc = other.maxDoc;
-    this.docBases = other.docBases;
-    this.startPointers = other.startPointers;
-    this.avgChunkDocs = other.avgChunkDocs;
-    this.avgChunkSizes = other.avgChunkSizes;
-    this.docBasesDeltas = other.docBasesDeltas;
-    this.startPointersDeltas = other.startPointersDeltas;
-  }
-
   private int block(int docID) {
     int lo = 0, hi = docBases.length - 1;
     while (lo <= hi) {
@@ -172,16 +158,7 @@
 
   @Override
   public CompressingStoredFieldsIndexReader clone() {
-    if (fieldsIndexIn == null) {
-      return this;
-    } else {
-      return new CompressingStoredFieldsIndexReader(this);
-    }
+    return this;
   }
 
-  @Override
-  public void close() throws IOException {
-    IOUtils.close(fieldsIndexIn);
-  }
-
 }
Index: lucene/core/src/java/org/apache/lucene/codecs/compressing/CompressingStoredFieldsReader.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/codecs/compressing/CompressingStoredFieldsReader.java	(revision 1491444)
+++ lucene/core/src/java/org/apache/lucene/codecs/compressing/CompressingStoredFieldsReader.java	(working copy)
@@ -96,20 +96,23 @@
     numDocs = si.getDocCount();
     IndexInput indexStream = null;
     try {
-      fieldsStream = d.openInput(IndexFileNames.segmentFileName(segment, segmentSuffix, FIELDS_EXTENSION), context);
+      // Load the index into memory
       final String indexStreamFN = IndexFileNames.segmentFileName(segment, segmentSuffix, FIELDS_INDEX_EXTENSION);
       indexStream = d.openInput(indexStreamFN, context);
-
       final String codecNameIdx = formatName + CODEC_SFX_IDX;
-      final String codecNameDat = formatName + CODEC_SFX_DAT;
       CodecUtil.checkHeader(indexStream, codecNameIdx, VERSION_START, VERSION_CURRENT);
-      CodecUtil.checkHeader(fieldsStream, codecNameDat, VERSION_START, VERSION_CURRENT);
-      assert CodecUtil.headerLength(codecNameDat) == fieldsStream.getFilePointer();
       assert CodecUtil.headerLength(codecNameIdx) == indexStream.getFilePointer();
-
       indexReader = new CompressingStoredFieldsIndexReader(indexStream, si);
+      indexStream.close();
       indexStream = null;
 
+      // Open the data file and read metadata
+      final String fieldsStreamFN = IndexFileNames.segmentFileName(segment, segmentSuffix, FIELDS_EXTENSION);
+      fieldsStream = d.openInput(fieldsStreamFN, context);
+      final String codecNameDat = formatName + CODEC_SFX_DAT;
+      CodecUtil.checkHeader(fieldsStream, codecNameDat, VERSION_START, VERSION_CURRENT);
+      assert CodecUtil.headerLength(codecNameDat) == fieldsStream.getFilePointer();
+
       packedIntsVersion = fieldsStream.readVInt();
       decompressor = compressionMode.newDecompressor();
       this.bytes = new BytesRef();
@@ -137,7 +140,7 @@
   @Override
   public void close() throws IOException {
     if (!closed) {
-      IOUtils.close(fieldsStream, indexReader);
+      IOUtils.close(fieldsStream);
       closed = true;
     }
   }
Index: lucene/CHANGES.txt
===================================================================
--- lucene/CHANGES.txt	(revision 1491444)
+++ lucene/CHANGES.txt	(working copy)
@@ -168,6 +168,9 @@
 * LUCENE-4941: Sort "from" terms only once when using JoinUtil.
   (Martijn van Groningen)
 
+* LUCENE-5050: Close the stored fields and term vectors index files as soon as
+  the index has been loaded into memory to save file descriptors. (Adrien Grand)
+
 New Features
 
 * LUCENE-4766: Added a PatternCaptureGroupTokenFilter that uses Java regexes to