diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/ReftableStack.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/ReftableStack.java new file mode 100644 index 000000000..8d1cc989d --- /dev/null +++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/ReftableStack.java @@ -0,0 +1,108 @@ +/* + * Copyright (C) 2017, 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.IOException; +import java.util.ArrayList; +import java.util.Collections; +import java.util.List; + +import org.eclipse.jgit.internal.storage.reftable.Reftable; + +/** Tracks multiple open {@link Reftable} instances. */ +public class ReftableStack implements AutoCloseable { + /** + * Opens a stack of tables for reading. + * + * @param ctx + * context to read the tables with. This {@code ctx} will be + * retained by the stack and each of the table readers. + * @param tables + * the tables to open. + * @return stack reference to close the tables. + * @throws IOException + * a table could not be opened + */ + public static ReftableStack open(DfsReader ctx, List tables) + throws IOException { + ReftableStack stack = new ReftableStack(tables.size()); + boolean close = true; + try { + for (DfsReftable t : tables) { + stack.tables.add(t.open(ctx)); + } + close = false; + return stack; + } finally { + if (close) { + stack.close(); + } + } + } + + private final List tables; + + private ReftableStack(int tableCnt) { + this.tables = new ArrayList<>(tableCnt); + } + + /** + * @return unmodifiable list of tables, in the same order the files were + * passed to {@link #open(DfsReader, List)}. + */ + public List readers() { + return Collections.unmodifiableList(tables); + } + + @Override + public void close() { + for (Reftable t : tables) { + try { + t.close(); + } catch (IOException e) { + // Ignore close failures. + } + } + } +}