org.eclipse.jgit/src/org/eclipse/jgit/notes/NoteMap.java - jgit - Git at Google

 /*
  * Copyright (C) 2010, 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.notes;

 import java.io.IOException;

 import org.eclipse.jgit.errors.CorruptObjectException;
 import org.eclipse.jgit.errors.IncorrectObjectTypeException;
 import org.eclipse.jgit.errors.LargeObjectException;
 import org.eclipse.jgit.errors.MissingObjectException;
 import org.eclipse.jgit.lib.AbbreviatedObjectId;
 import org.eclipse.jgit.lib.AnyObjectId;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectReader;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevTree;

 /**
  * Index of notes from a note branch.
  *
  * This class is not thread-safe, and relies on an {@link ObjectReader} that it
  * borrows/shares with the caller. The reader can be used during any call, and
  * is not released by this class. The caller should arrange for releasing the
  * shared {@code ObjectReader} at the proper times.
  */
 public class NoteMap {
 	/**
 	 * Load a collection of notes from a branch.
 	 *
 	 * @param reader
 	 *            reader to scan the note branch with. This reader may be
 	 *            retained by the NoteMap for the life of the map in order to
 	 *            support lazy loading of entries.
 	 * @param commit
 	 *            the revision of the note branch to read.
 	 * @return the note map read from the commit.
 	 * @throws IOException
 	 *             the repository cannot be accessed through the reader.
 	 * @throws CorruptObjectException
 	 *             a tree object is corrupt and cannot be read.
 	 * @throws IncorrectObjectTypeException
 	 *             a tree object wasn't actually a tree.
 	 * @throws MissingObjectException
 	 *             a reference tree object doesn't exist.
 	 */
 	public static NoteMap read(ObjectReader reader, RevCommit commit)
 			throws MissingObjectException, IncorrectObjectTypeException,
 			CorruptObjectException, IOException {
 		return read(reader, commit.getTree());
 	}

 	/**
 	 * Load a collection of notes from a tree.
 	 *
 	 * @param reader
 	 *            reader to scan the note branch with. This reader may be
 	 *            retained by the NoteMap for the life of the map in order to
 	 *            support lazy loading of entries.
 	 * @param tree
 	 *            the note tree to read.
 	 * @return the note map read from the tree.
 	 * @throws IOException
 	 *             the repository cannot be accessed through the reader.
 	 * @throws CorruptObjectException
 	 *             a tree object is corrupt and cannot be read.
 	 * @throws IncorrectObjectTypeException
 	 *             a tree object wasn't actually a tree.
 	 * @throws MissingObjectException
 	 *             a reference tree object doesn't exist.
 	 */
 	public static NoteMap read(ObjectReader reader, RevTree tree)
 			throws MissingObjectException, IncorrectObjectTypeException,
 			CorruptObjectException, IOException {
 		return readTree(reader, tree);
 	}

 	/**
 	 * Load a collection of notes from a tree.
 	 *
 	 * @param reader
 	 *            reader to scan the note branch with. This reader may be
 	 *            retained by the NoteMap for the life of the map in order to
 	 *            support lazy loading of entries.
 	 * @param treeId
 	 *            the note tree to read.
 	 * @return the note map read from the tree.
 	 * @throws IOException
 	 *             the repository cannot be accessed through the reader.
 	 * @throws CorruptObjectException
 	 *             a tree object is corrupt and cannot be read.
 	 * @throws IncorrectObjectTypeException
 	 *             a tree object wasn't actually a tree.
 	 * @throws MissingObjectException
 	 *             a reference tree object doesn't exist.
 	 */
 	public static NoteMap readTree(ObjectReader reader, ObjectId treeId)
 			throws MissingObjectException, IncorrectObjectTypeException,
 			CorruptObjectException, IOException {
 		NoteMap map = new NoteMap(reader);
 		map.load(treeId);
 		return map;
 	}

 	/** Borrowed reader to access the repository. */
 	private final ObjectReader reader;

 	/** All of the notes that have been loaded. */
 	private InMemoryNoteBucket root;

 	private NoteMap(ObjectReader reader) {
 		this.reader = reader;
 	}

 	/**
 	 * Lookup a note for a specific ObjectId.
 	 *
 	 * @param id
 	 *            the object to look for.
 	 * @return the note's blob ObjectId, or null if no note exists.
 	 * @throws IOException
 	 *             a portion of the note space is not accessible.
 	 */
 	public ObjectId get(AnyObjectId id) throws IOException {
 		return root.get(id, reader);
 	}

 	/**
 	 * Determine if a note exists for the specified ObjectId.
 	 *
 	 * @param id
 	 *            the object to look for.
 	 * @return true if a note exists; false if there is no note.
 	 * @throws IOException
 	 *             a portion of the note space is not accessible.
 	 */
 	public boolean contains(AnyObjectId id) throws IOException {
 		return get(id) != null;
 	}

 	/**
 	 * Open and return the content of an object's note.
 	 *
 	 * This method assumes the note is fairly small and can be accessed
 	 * efficiently. Larger notes should be accessed by streaming:
 	 *
 	 * <pre>
 	 * ObjectId dataId = thisMap.get(id);
 	 * if (dataId != null)
 	 * 	reader.open(dataId).openStream();
 	 * </pre>
 	 *
 	 * @param id
 	 *            object to lookup the note of.
 	 * @param sizeLimit
 	 *            maximum number of bytes to return. If the note data size is
 	 *            larger than this limit, LargeObjectException will be thrown.
 	 * @return if a note is defined for {@code id}, the note content. If no note
 	 *         is defined, null.
 	 * @throws LargeObjectException
 	 *             the note data is larger than {@code sizeLimit}.
 	 * @throws MissingObjectException
 	 *             the note's blob does not exist in the repository.
 	 * @throws IOException
 	 *             the note's blob cannot be read from the repository
 	 */
 	public byte[] getCachedBytes(AnyObjectId id, int sizeLimit)
 			throws LargeObjectException, MissingObjectException, IOException {
 		ObjectId dataId = get(id);
 		if (dataId != null)
 			return reader.open(dataId).getCachedBytes(sizeLimit);
 		else
 			return null;
 	}

 	private void load(ObjectId rootTree) throws MissingObjectException,
 			IncorrectObjectTypeException, CorruptObjectException, IOException {
 		AbbreviatedObjectId none = AbbreviatedObjectId.fromString("");
 		root = NoteParser.parse(none, rootTree, reader);
 	}
 }
	/*
	* Copyright (C) 2010, 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.notes;

	import java.io.IOException;

	import org.eclipse.jgit.errors.CorruptObjectException;
	import org.eclipse.jgit.errors.IncorrectObjectTypeException;
	import org.eclipse.jgit.errors.LargeObjectException;
	import org.eclipse.jgit.errors.MissingObjectException;
	import org.eclipse.jgit.lib.AbbreviatedObjectId;
	import org.eclipse.jgit.lib.AnyObjectId;
	import org.eclipse.jgit.lib.ObjectId;
	import org.eclipse.jgit.lib.ObjectReader;
	import org.eclipse.jgit.revwalk.RevCommit;
	import org.eclipse.jgit.revwalk.RevTree;

	/**
	* Index of notes from a note branch.
	*
	* This class is not thread-safe, and relies on an {@link ObjectReader} that it
	* borrows/shares with the caller. The reader can be used during any call, and
	* is not released by this class. The caller should arrange for releasing the
	* shared {@code ObjectReader} at the proper times.
	*/
	public class NoteMap {
	/**
	* Load a collection of notes from a branch.
	*
	* @param reader
	* reader to scan the note branch with. This reader may be
	* retained by the NoteMap for the life of the map in order to
	* support lazy loading of entries.
	* @param commit
	* the revision of the note branch to read.
	* @return the note map read from the commit.
	* @throws IOException
	* the repository cannot be accessed through the reader.
	* @throws CorruptObjectException
	* a tree object is corrupt and cannot be read.
	* @throws IncorrectObjectTypeException
	* a tree object wasn't actually a tree.
	* @throws MissingObjectException
	* a reference tree object doesn't exist.
	*/
	public static NoteMap read(ObjectReader reader, RevCommit commit)
	throws MissingObjectException, IncorrectObjectTypeException,
	CorruptObjectException, IOException {
	return read(reader, commit.getTree());
	}

	/**
	* Load a collection of notes from a tree.
	*
	* @param reader
	* reader to scan the note branch with. This reader may be
	* retained by the NoteMap for the life of the map in order to
	* support lazy loading of entries.
	* @param tree
	* the note tree to read.
	* @return the note map read from the tree.
	* @throws IOException
	* the repository cannot be accessed through the reader.
	* @throws CorruptObjectException
	* a tree object is corrupt and cannot be read.
	* @throws IncorrectObjectTypeException
	* a tree object wasn't actually a tree.
	* @throws MissingObjectException
	* a reference tree object doesn't exist.
	*/
	public static NoteMap read(ObjectReader reader, RevTree tree)
	throws MissingObjectException, IncorrectObjectTypeException,
	CorruptObjectException, IOException {
	return readTree(reader, tree);
	}

	/**
	* Load a collection of notes from a tree.
	*
	* @param reader
	* reader to scan the note branch with. This reader may be
	* retained by the NoteMap for the life of the map in order to
	* support lazy loading of entries.
	* @param treeId
	* the note tree to read.
	* @return the note map read from the tree.
	* @throws IOException
	* the repository cannot be accessed through the reader.
	* @throws CorruptObjectException
	* a tree object is corrupt and cannot be read.
	* @throws IncorrectObjectTypeException
	* a tree object wasn't actually a tree.
	* @throws MissingObjectException
	* a reference tree object doesn't exist.
	*/
	public static NoteMap readTree(ObjectReader reader, ObjectId treeId)
	throws MissingObjectException, IncorrectObjectTypeException,
	CorruptObjectException, IOException {
	NoteMap map = new NoteMap(reader);
	map.load(treeId);
	return map;
	}

	/** Borrowed reader to access the repository. */
	private final ObjectReader reader;

	/** All of the notes that have been loaded. */
	private InMemoryNoteBucket root;

	private NoteMap(ObjectReader reader) {
	this.reader = reader;
	}

	/**
	* Lookup a note for a specific ObjectId.
	*
	* @param id
	* the object to look for.
	* @return the note's blob ObjectId, or null if no note exists.
	* @throws IOException
	* a portion of the note space is not accessible.
	*/
	public ObjectId get(AnyObjectId id) throws IOException {
	return root.get(id, reader);
	}

	/**
	* Determine if a note exists for the specified ObjectId.
	*
	* @param id
	* the object to look for.
	* @return true if a note exists; false if there is no note.
	* @throws IOException
	* a portion of the note space is not accessible.
	*/
	public boolean contains(AnyObjectId id) throws IOException {
	return get(id) != null;
	}

	/**
	* Open and return the content of an object's note.
	*
	* This method assumes the note is fairly small and can be accessed
	* efficiently. Larger notes should be accessed by streaming:
	*
	* <pre>
	* ObjectId dataId = thisMap.get(id);
	* if (dataId != null)
	* reader.open(dataId).openStream();
	* </pre>
	*
	* @param id
	* object to lookup the note of.
	* @param sizeLimit
	* maximum number of bytes to return. If the note data size is
	* larger than this limit, LargeObjectException will be thrown.
	* @return if a note is defined for {@code id}, the note content. If no note
	* is defined, null.
	* @throws LargeObjectException
	* the note data is larger than {@code sizeLimit}.
	* @throws MissingObjectException
	* the note's blob does not exist in the repository.
	* @throws IOException
	* the note's blob cannot be read from the repository
	*/
	public byte[] getCachedBytes(AnyObjectId id, int sizeLimit)
	throws LargeObjectException, MissingObjectException, IOException {
	ObjectId dataId = get(id);
	if (dataId != null)
	return reader.open(dataId).getCachedBytes(sizeLimit);
	else
	return null;
	}

	private void load(ObjectId rootTree) throws MissingObjectException,
	IncorrectObjectTypeException, CorruptObjectException, IOException {
	AbbreviatedObjectId none = AbbreviatedObjectId.fromString("");
	root = NoteParser.parse(none, rootTree, reader);
	}
	}