Index: lucene/core/src/java/org/apache/lucene/index/DirectoryReader.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/index/DirectoryReader.java	(revision 1491970)
+++ lucene/core/src/java/org/apache/lucene/index/DirectoryReader.java	(working copy)
@@ -19,6 +19,7 @@
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.NoSuchFileException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -291,7 +292,7 @@
           // IOException allowed to throw there, in case
           // segments_N is corrupt
           sis.read(dir, fileName);
-        } catch (FileNotFoundException fnfe) {
+        } catch (FileNotFoundException | NoSuchFileException fnfe) {
           // LUCENE-948: on NFS (and maybe others), if
           // you have writers switching back and forth
           // between machines, it's very likely that the
Index: lucene/core/src/java/org/apache/lucene/index/IndexFileDeleter.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/index/IndexFileDeleter.java	(revision 1491970)
+++ lucene/core/src/java/org/apache/lucene/index/IndexFileDeleter.java	(working copy)
@@ -20,6 +20,7 @@
 import java.io.Closeable;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.NoSuchFileException;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -170,7 +171,7 @@
             SegmentInfos sis = new SegmentInfos();
             try {
               sis.read(directory, fileName);
-            } catch (FileNotFoundException e) {
+            } catch (FileNotFoundException | NoSuchFileException e) {
               // LUCENE-948: on NFS (and maybe others), if
               // you have writers switching back and forth
               // between machines, it's very likely that the
Index: lucene/core/src/java/org/apache/lucene/index/SegmentInfos.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/index/SegmentInfos.java	(revision 1491970)
+++ lucene/core/src/java/org/apache/lucene/index/SegmentInfos.java	(working copy)
@@ -17,7 +17,6 @@
  * limitations under the License.
  */
 
-import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.PrintStream;
 import java.util.ArrayList;
Index: lucene/core/src/java/org/apache/lucene/store/Directory.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/store/Directory.java	(revision 1491970)
+++ lucene/core/src/java/org/apache/lucene/store/Directory.java	(working copy)
@@ -21,6 +21,7 @@
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.Closeable;
+import java.nio.file.NoSuchFileException;
 import java.util.Collection; // for javadocs
 
 import org.apache.lucene.util.IOUtils;
@@ -70,12 +71,12 @@
    * Returns the length of a file in the directory. This method follows the
    * following contract:
    * <ul>
-   * <li>Throws {@link FileNotFoundException} if the file does not exist
+   * <li>Throws {@link FileNotFoundException} or {@link NoSuchFileException}
+   * if the file does not exist.
    * <li>Returns a value &ge;0 if the file exists, which specifies its length.
    * </ul>
    * 
    * @param name the name of the file for which to return the length.
-   * @throws FileNotFoundException if the file does not exist.
    * @throws IOException if there was an IO error while retrieving the file's
    *         length.
    */
@@ -106,7 +107,9 @@
    * the only Directory implementations that respect this
    * parameter are {@link FSDirectory} and {@link
    * CompoundFileDirectory}.
-  */
+   * <p>Throws {@link FileNotFoundException} or {@link NoSuchFileException}
+   * if the file does not exist.
+   */
   public abstract IndexInput openInput(String name, IOContext context) throws IOException; 
   
   /** Construct a {@link Lock}.
@@ -223,6 +226,8 @@
    * efficiently open one or more sliced {@link IndexInput} instances from a
    * single file handle. The underlying file handle is kept open until the
    * {@link IndexInputSlicer} is closed.
+   * <p>Throws {@link FileNotFoundException} or {@link NoSuchFileException}
+   * if the file does not exist.
    *
    * @throws IOException
    *           if an {@link IOException} occurs
Index: lucene/core/src/test/org/apache/lucene/index/TestAddIndexes.java
===================================================================
--- lucene/core/src/test/org/apache/lucene/index/TestAddIndexes.java	(revision 1491970)
+++ lucene/core/src/test/org/apache/lucene/index/TestAddIndexes.java	(working copy)
@@ -19,6 +19,7 @@
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.NoSuchFileException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -888,7 +889,7 @@
 
       if (t instanceof AlreadyClosedException || t instanceof MergePolicy.MergeAbortedException || t instanceof NullPointerException) {
         report = !didClose;
-      } else if (t instanceof FileNotFoundException)  {
+      } else if (t instanceof FileNotFoundException || t instanceof NoSuchFileException)  {
         report = !didClose;
       } else if (t instanceof IOException)  {
         Throwable t2 = t.getCause();
Index: lucene/core/src/test/org/apache/lucene/index/TestDirectoryReader.java
===================================================================
--- lucene/core/src/test/org/apache/lucene/index/TestDirectoryReader.java	(revision 1491970)
+++ lucene/core/src/test/org/apache/lucene/index/TestDirectoryReader.java	(working copy)
@@ -20,6 +20,7 @@
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.NoSuchFileException;
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.Iterator;
@@ -428,8 +429,8 @@
     }
     try {
       DirectoryReader.open(fileDirName);
-      fail("opening DirectoryReader on empty directory failed to produce FileNotFoundException");
-    } catch (FileNotFoundException e) {
+      fail("opening DirectoryReader on empty directory failed to produce FileNotFoundException/NoSuchFileException");
+    } catch (FileNotFoundException | NoSuchFileException e) {
       // GOOD
     }
     rmDir(fileDirName);
@@ -470,8 +471,8 @@
     Directory dir = newFSDirectory(dirFile);
     try {
       DirectoryReader.open(dir);
-      fail("expected FileNotFoundException");
-    } catch (FileNotFoundException e) {
+      fail("expected FileNotFoundException/NoSuchFileException");
+    } catch (FileNotFoundException | NoSuchFileException e) {
       // expected
     }
 
@@ -480,8 +481,8 @@
     // Make sure we still get a CorruptIndexException (not NPE):
     try {
       DirectoryReader.open(dir);
-      fail("expected FileNotFoundException");
-    } catch (FileNotFoundException e) {
+      fail("expected FileNotFoundException/NoSuchFileException");
+    } catch (FileNotFoundException | NoSuchFileException e) {
       // expected
     }
     
Index: lucene/core/src/test/org/apache/lucene/index/TestIndexWriterExceptions.java
===================================================================
--- lucene/core/src/test/org/apache/lucene/index/TestIndexWriterExceptions.java	(revision 1491970)
+++ lucene/core/src/test/org/apache/lucene/index/TestIndexWriterExceptions.java	(working copy)
@@ -21,6 +21,7 @@
 import java.io.IOException;
 import java.io.Reader;
 import java.io.StringReader;
+import java.nio.file.NoSuchFileException;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
@@ -1671,7 +1672,7 @@
       } catch (CorruptIndexException ex) {
         // Exceptions are fine - we are running out of file handlers here
         continue;
-      } catch (FileNotFoundException ex) {
+      } catch (FileNotFoundException | NoSuchFileException ex) {
         continue;
       }
       failure.clearDoFail();
Index: lucene/core/src/test/org/apache/lucene/index/TestIndexWriterLockRelease.java
===================================================================
--- lucene/core/src/test/org/apache/lucene/index/TestIndexWriterLockRelease.java	(revision 1491970)
+++ lucene/core/src/test/org/apache/lucene/index/TestIndexWriterLockRelease.java	(working copy)
@@ -19,6 +19,7 @@
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.NoSuchFileException;
 
 import org.apache.lucene.analysis.MockAnalyzer;
 import org.apache.lucene.index.IndexWriterConfig.OpenMode;
@@ -37,10 +38,10 @@
     Directory dir = newFSDirectory(_TestUtil.getTempDir("testLockRelease"));
     try {
       new IndexWriter(dir, new IndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random())).setOpenMode(OpenMode.APPEND));
-    } catch (FileNotFoundException e) {
+    } catch (FileNotFoundException | NoSuchFileException e) {
       try {
         new IndexWriter(dir, new IndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random())).setOpenMode(OpenMode.APPEND));
-      } catch (FileNotFoundException e1) {
+      } catch (FileNotFoundException | NoSuchFileException e1) {
       }
     } finally {
       dir.close();
Index: lucene/core/src/test/org/apache/lucene/store/TestDirectory.java
===================================================================
--- lucene/core/src/test/org/apache/lucene/store/TestDirectory.java	(revision 1491970)
+++ lucene/core/src/test/org/apache/lucene/store/TestDirectory.java	(working copy)
@@ -20,6 +20,7 @@
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.NoSuchFileException;
 import java.util.Arrays;
 
 import org.apache.lucene.store.MockDirectoryWrapper.Throttling;
@@ -98,7 +99,7 @@
              try {
               IndexInput input = dir.openInput(file, newIOContext(random()));
               input.close();
-              } catch (FileNotFoundException e) {
+              } catch (FileNotFoundException | NoSuchFileException e) {
                 // ignore
               } catch (IOException e) {
                 if (e.getMessage().contains("still open for writing")) {
Index: lucene/replicator/src/test/org/apache/lucene/replicator/LocalReplicatorTest.java
===================================================================
--- lucene/replicator/src/test/org/apache/lucene/replicator/LocalReplicatorTest.java	(revision 1491970)
+++ lucene/replicator/src/test/org/apache/lucene/replicator/LocalReplicatorTest.java	(working copy)
@@ -155,10 +155,8 @@
     try {
       replicator.obtainFile(res.id, res.sourceFiles.keySet().iterator().next(), "madeUpFile");
       fail("should have failed obtaining an unrecognized file");
-    } catch (FileNotFoundException e) {
+    } catch (FileNotFoundException | NoSuchFileException e) {
       // expected
-    } catch (NoSuchFileException e) {
-      // expected (only java 1.7)
     }
   }
   
Index: lucene/test-framework/src/java/org/apache/lucene/store/MockDirectoryWrapper.java
===================================================================
--- lucene/test-framework/src/java/org/apache/lucene/store/MockDirectoryWrapper.java	(revision 1491970)
+++ lucene/test-framework/src/java/org/apache/lucene/store/MockDirectoryWrapper.java	(working copy)
@@ -20,6 +20,7 @@
 import java.io.Closeable;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.NoSuchFileException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -385,7 +386,7 @@
       if (randomState.nextBoolean()) {
         throw new IOException("a random IOException (" + name + ")");
       } else {
-        throw new FileNotFoundException("a random IOException (" + name + ")");
+        throw randomState.nextBoolean() ? new FileNotFoundException("a random IOException (" + name + ")") : new NoSuchFileException("a random IOException (" + name + ")");
       }
     }
   }
@@ -544,7 +545,7 @@
       maybeThrowDeterministicException();
     }
     if (!delegate.fileExists(name)) {
-      throw new FileNotFoundException(name + " in dir=" + delegate);
+      throw randomState.nextBoolean() ? new FileNotFoundException(name + " in dir=" + delegate) : new NoSuchFileException(name + " in dir=" + delegate);
     }
 
     // cannot open a file for input if it's still open for
@@ -920,7 +921,7 @@
       throws IOException {
     maybeYield();
     if (!delegate.fileExists(name)) {
-      throw new FileNotFoundException(name);
+      throw randomState.nextBoolean() ? new FileNotFoundException(name) : new NoSuchFileException(name);
     }
     // cannot open a file for input if it's still open for
     // output, except for segments.gen and segments_N