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- /*
- * Copyright (C) 2010, Constantine Plotnikov <constantine.plotnikov@gmail.com>
- * Copyright (C) 2010, JetBrains s.r.o.
- * 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.util.Collection;
-
- /**
- * {@link ObjectDatabase} wrapper providing temporary lookup caching.
- * <p>
- * The base class for {@code ObjectDatabase}s that wrap other database instances
- * and optimize querying for objects by caching some database dependent
- * information. Instances of this class (or any of its subclasses) can be
- * returned from the method {@link ObjectDatabase#newCachedDatabase()}. This
- * class can be used in scenarios where the database does not change, or when
- * changes in the database while some operation is in progress is an acceptable
- * risk.
- * <p>
- * The default implementation delegates all requests to the wrapped database.
- * The instance might be indirectly invalidated if the wrapped instance is
- * closed. Closing the delegating instance does not implies closing the wrapped
- * instance. For alternative databases, cached instances are used as well.
- */
- public class CachedObjectDatabase extends ObjectDatabase {
- /**
- * The wrapped database instance
- */
- protected final ObjectDatabase wrapped;
-
- /**
- * Create the delegating database instance
- *
- * @param wrapped
- * the wrapped object database
- */
- public CachedObjectDatabase(ObjectDatabase wrapped) {
- this.wrapped = wrapped;
- }
-
- @Override
- protected boolean hasObject1(AnyObjectId objectId) {
- return wrapped.hasObject1(objectId);
- }
-
- @Override
- protected ObjectLoader openObject1(WindowCursor curs, AnyObjectId objectId)
- throws IOException {
- return wrapped.openObject1(curs, objectId);
- }
-
- @Override
- protected boolean hasObject2(String objectName) {
- return wrapped.hasObject2(objectName);
- }
-
- @Override
- protected ObjectDatabase[] loadAlternates() throws IOException {
- ObjectDatabase[] loaded = wrapped.getAlternates();
- ObjectDatabase[] result = new ObjectDatabase[loaded.length];
- for (int i = 0; i < loaded.length; i++) {
- result[i] = loaded[i].newCachedDatabase();
- }
- return result;
- }
-
- @Override
- protected ObjectLoader openObject2(WindowCursor curs, String objectName,
- AnyObjectId objectId) throws IOException {
- return wrapped.openObject2(curs, objectName, objectId);
- }
-
- @Override
- void openObjectInAllPacks1(Collection<PackedObjectLoader> out,
- WindowCursor curs, AnyObjectId objectId) throws IOException {
- wrapped.openObjectInAllPacks1(out, curs, objectId);
- }
-
- @Override
- protected boolean tryAgain1() {
- return wrapped.tryAgain1();
- }
-
- @Override
- public ObjectDatabase newCachedDatabase() {
- // Note that "this" is not returned since subclasses might actually do something,
- // on closeSelf() (for example closing database connections or open repositories).
- // The situation might become even more tricky if we will consider alternates.
- return wrapped.newCachedDatabase();
- }
- }
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