Revert "Add a method to DfsOutputStream to read as an InputStream"

This reverts commit b646578d89513c5db30151f0b865c7335c88d682.

openInputStream() is never used in JGit, nor is it used by any
known working DFS implementation. The method was added as a
utility for reading back from a DfsInserter, but the final
implementation of that feature does not requrire this method.

Change-Id: I075ad95e40af49c92b554480f8993ef5658f7684

3 files changed, 39 insertions, 145 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsOutputStream.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsOutputStream.java
index acd92d7d85..ef3173e87d 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsOutputStream.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsOutputStream.java
@@ -44,7 +44,6 @@
 package org.eclipse.jgit.internal.storage.dfs;
 
 import java.io.IOException;
-import java.io.InputStream;
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
 
@@ -97,62 +96,4 @@ public abstract class DfsOutputStream extends OutputStream {
 	 *             to DFS errors.
 	 */
 	public abstract int read(long position, ByteBuffer buf) throws IOException;
-
-	/**
-	 * Open a stream to read back a portion of already written data.
-	 * <p>
-	 * The writing position of the output stream is not affected by a read. The
-	 * input stream can be read up to the current writing position. Closing the
-	 * returned stream has no effect on the underlying {@link DfsOutputStream}.
-	 *
-	 * @param position
-	 *            offset to read from.
-	 * @return new input stream
-	 */
-	public InputStream openInputStream(final long position) {
-		return new ReadBackStream(position);
-	}
-
-	private class ReadBackStream extends InputStream {
-		private final ByteBuffer buf;
-		private long position;
-
-		private ReadBackStream(long position) {
-			int bs = blockSize();
-			this.position = position;
-			buf = ByteBuffer.allocate(bs > 0 ? bs : 8192);
-			buf.position(buf.limit());
-		}
-
-		@Override
-		public int read(byte[] b, int off, int len) throws IOException {
-			int cnt = 0;
-			while (0 < len) {
-				if (!buf.hasRemaining()) {
-					buf.rewind();
-					int nr = DfsOutputStream.this.read(position, buf);
-					if (nr < 0) {
-						buf.position(buf.limit());
-						break;
-					}
-					position += nr;
-					buf.flip();
-				}
-				int n = Math.min(len, buf.remaining());
-				buf.get(b, off, n);
-				off += n;
-				len -= n;
-				cnt += n;
-			}
-			if (cnt == 0 && len > 0) return -1;
-			return cnt;
-		}
-
-		@Override
-		public int read() throws IOException {
-			byte[] b = new byte[1];
-			int n = read(b);
-			return n == 1 ? b[0] & 0xff : -1;
-		}
-	}
 }
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/InMemoryOutputStream.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/InMemoryOutputStream.java
deleted file mode 100644
index 9a5f6a6084..0000000000
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/InMemoryOutputStream.java
+++ /dev/null
@@ -1,85 +0,0 @@
-/*
- * Copyright (C) 2013, Google Inc.
- * and other copyright owners as documented in the project's IP log.
- *
- * This program and the accompanying materials are made available
- * under the terms of the Eclipse Distribution License v1.0 which
- * accompanies this distribution, is reproduced below, and is
- * available at http://www.eclipse.org/org/documents/edl-v10.php
- *
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or
- * without modification, are permitted provided that the following
- * conditions are met:
- *
- * - Redistributions of source code must retain the above copyright
- *   notice, this list of conditions and the following disclaimer.
- *
- * - Redistributions in binary form must reproduce the above
- *   copyright notice, this list of conditions and the following
- *   disclaimer in the documentation and/or other materials provided
- *   with the distribution.
- *
- * - Neither the name of the Eclipse Foundation, Inc. nor the
- *   names of its contributors may be used to endorse or promote
- *   products derived from this software without specific prior
- *   written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
- * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
- * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
- * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
- * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-package org.eclipse.jgit.internal.storage.dfs;
-
-import java.io.ByteArrayOutputStream;
-import java.nio.ByteBuffer;
-
-class InMemoryOutputStream extends DfsOutputStream {
-	private final ByteArrayOutputStream dst = new ByteArrayOutputStream();
-
-	private byte[] data;
-
-	@Override
-	public void write(byte[] buf, int off, int len) {
-		data = null;
-		dst.write(buf, off, len);
-	}
-
-	@Override
-	public int read(long position, ByteBuffer buf) {
-		byte[] d = getData();
-		int n = Math.min(buf.remaining(), d.length - (int) position);
-		if (n <= 0)
-			return -1;
-		buf.put(d, (int) position, n);
-		return n;
-	}
-
-	byte[] getData() {
-		if (data == null)
-			data = dst.toByteArray();
-		return data;
-	}
-
-	@Override
-	public void flush() {
-		// Default implementation does nothing;
-	}
-
-	@Override
-	public void close() {
-		flush();
-	}
-}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/InMemoryRepository.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/InMemoryRepository.java
index fe4625b547..56efdd683c 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/InMemoryRepository.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/InMemoryRepository.java
@@ -1,5 +1,6 @@
 package org.eclipse.jgit.internal.storage.dfs;
 
+import java.io.ByteArrayOutputStream;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.nio.ByteBuffer;
@@ -116,7 +117,7 @@ public class InMemoryRepository extends DfsRepository {
 		protected DfsOutputStream writeFile(
 				DfsPackDescription desc, final PackExt ext) throws IOException {
 			final MemPack memPack = (MemPack) desc;
-			return new InMemoryOutputStream() {
+			return new Out() {
 				@Override
 				public void flush() {
 					memPack.fileMap.put(ext, getData());
@@ -134,6 +135,43 @@ public class InMemoryRepository extends DfsRepository {
 		}
 	}
 
+	private abstract static class Out extends DfsOutputStream {
+		private final ByteArrayOutputStream dst = new ByteArrayOutputStream();
+
+		private byte[] data;
+
+		@Override
+		public void write(byte[] buf, int off, int len) {
+			data = null;
+			dst.write(buf, off, len);
+		}
+
+		@Override
+		public int read(long position, ByteBuffer buf) {
+			byte[] d = getData();
+			int n = Math.min(buf.remaining(), d.length - (int) position);
+			if (n == 0)
+				return -1;
+			buf.put(d, (int) position, n);
+			return n;
+		}
+
+		byte[] getData() {
+			if (data == null)
+				data = dst.toByteArray();
+			return data;
+		}
+
+		@Override
+		public abstract void flush();
+
+		@Override
+		public void close() {
+			flush();
+		}
+
+	}
+
 	private static class ByteArrayReadableChannel implements ReadableChannel {
 		private final byte[] data;