| /* |
| * Copyright (C) 2019, Google LLC |
| * 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.reftable; |
| |
| import org.eclipse.jgit.lib.ReflogEntry; |
| import org.eclipse.jgit.lib.ReflogReader; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.concurrent.locks.Lock; |
| |
| /** |
| * Implement the ReflogReader interface for a reflog stored in reftable. |
| */ |
| public class ReftableReflogReader implements ReflogReader { |
| private final Lock lock; |
| |
| private final Reftable reftable; |
| |
| private final String refname; |
| |
| ReftableReflogReader(Lock lock, Reftable merged, String refname) { |
| this.lock = lock; |
| this.reftable = merged; |
| this.refname = refname; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public ReflogEntry getLastEntry() throws IOException { |
| lock.lock(); |
| try { |
| LogCursor cursor = reftable.seekLog(refname); |
| return cursor.next() ? cursor.getReflogEntry() : null; |
| } finally { |
| lock.unlock(); |
| } |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public List<ReflogEntry> getReverseEntries() throws IOException { |
| return getReverseEntries(Integer.MAX_VALUE); |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public ReflogEntry getReverseEntry(int number) throws IOException { |
| lock.lock(); |
| try { |
| LogCursor cursor = reftable.seekLog(refname); |
| while (true) { |
| if (!cursor.next() || number < 0) { |
| return null; |
| } |
| if (number == 0) { |
| return cursor.getReflogEntry(); |
| } |
| number--; |
| } |
| } finally { |
| lock.unlock(); |
| } |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public List<ReflogEntry> getReverseEntries(int max) throws IOException { |
| lock.lock(); |
| try { |
| LogCursor cursor = reftable.seekLog(refname); |
| |
| List<ReflogEntry> result = new ArrayList<>(); |
| while (cursor.next() && result.size() < max) { |
| result.add(cursor.getReflogEntry()); |
| } |
| |
| return result; |
| } finally { |
| lock.unlock(); |
| } |
| } |
| } |