| /* |
| * Copyright (C) 2009, Google Inc. |
| * Copyright (C) 2008, Marek Zawirski <marek.zawirski@gmail.com> |
| * Copyright (C) 2007, Robin Rosenberg <robin.rosenberg@dewire.com> |
| * Copyright (C) 2006-2008, Shawn O. Pearce <spearce@spearce.org> |
| * 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.lib; |
| |
| import java.io.IOException; |
| import java.io.OutputStream; |
| |
| /** |
| * Base class for a set of object loader classes for packed objects. |
| */ |
| abstract class PackedObjectLoader extends ObjectLoader { |
| protected final PackFile pack; |
| |
| protected final long dataOffset; |
| |
| protected final long objectOffset; |
| |
| protected int objectType; |
| |
| protected int objectSize; |
| |
| protected byte[] cachedBytes; |
| |
| PackedObjectLoader(final PackFile pr, final long dataOffset, |
| final long objectOffset) { |
| pack = pr; |
| this.dataOffset = dataOffset; |
| this.objectOffset = objectOffset; |
| } |
| |
| /** |
| * Force this object to be loaded into memory and pinned in this loader. |
| * <p> |
| * Once materialized, subsequent get operations for the following methods |
| * will always succeed without raising an exception, as all information is |
| * pinned in memory by this loader instance. |
| * <ul> |
| * <li>{@link #getType()}</li> |
| * <li>{@link #getSize()}</li> |
| * <li>{@link #getBytes()}, {@link #getCachedBytes}</li> |
| * <li>{@link #getRawSize()}</li> |
| * <li>{@link #getRawType()}</li> |
| * </ul> |
| * |
| * @param curs |
| * temporary thread storage during data access. |
| * @throws IOException |
| * the object cannot be read. |
| */ |
| public abstract void materialize(WindowCursor curs) throws IOException; |
| |
| public final int getType() { |
| return objectType; |
| } |
| |
| public final long getSize() { |
| return objectSize; |
| } |
| |
| @Override |
| public final byte[] getCachedBytes() { |
| return cachedBytes; |
| } |
| |
| /** |
| * @return offset of object header within pack file |
| */ |
| public final long getObjectOffset() { |
| return objectOffset; |
| } |
| |
| /** |
| * @return offset of object data within pack file |
| */ |
| public final long getDataOffset() { |
| return dataOffset; |
| } |
| |
| /** |
| * Peg the pack file open to support data copying. |
| * <p> |
| * Applications trying to copy raw pack data should ensure the pack stays |
| * open and available throughout the entire copy. To do that use: |
| * |
| * <pre> |
| * loader.beginCopyRawData(); |
| * try { |
| * loader.copyRawData(out, tmpbuf, curs); |
| * } finally { |
| * loader.endCopyRawData(); |
| * } |
| * </pre> |
| * |
| * @throws IOException |
| * this loader contains stale information and cannot be used. |
| * The most likely cause is the underlying pack file has been |
| * deleted, and the object has moved to another pack file. |
| */ |
| public void beginCopyRawData() throws IOException { |
| pack.beginCopyRawData(); |
| } |
| |
| /** |
| * Copy raw object representation from storage to provided output stream. |
| * <p> |
| * Copied data doesn't include object header. User must provide temporary |
| * buffer used during copying by underlying I/O layer. |
| * </p> |
| * |
| * @param out |
| * output stream when data is copied. No buffering is guaranteed. |
| * @param buf |
| * temporary buffer used during copying. Recommended size is at |
| * least few kB. |
| * @param curs |
| * temporary thread storage during data access. |
| * @throws IOException |
| * when the object cannot be read. |
| * @see #beginCopyRawData() |
| */ |
| public void copyRawData(OutputStream out, byte buf[], WindowCursor curs) |
| throws IOException { |
| pack.copyRawData(this, out, buf, curs); |
| } |
| |
| /** Release resources after {@link #beginCopyRawData()}. */ |
| public void endCopyRawData() { |
| pack.endCopyRawData(); |
| } |
| |
| /** |
| * @return true if this loader is capable of fast raw-data copying basing on |
| * compressed data checksum; false if raw-data copying needs |
| * uncompressing and compressing data |
| * @throws IOException |
| * the index file format cannot be determined. |
| */ |
| public boolean supportsFastCopyRawData() throws IOException { |
| return pack.supportsFastCopyRawData(); |
| } |
| |
| /** |
| * @return id of delta base object for this object representation. null if |
| * object is not stored as delta. |
| * @throws IOException |
| * when delta base cannot read. |
| */ |
| public abstract ObjectId getDeltaBase() throws IOException; |
| } |