Java tutorial
/* * Copyright (C) 2009, Constantine Plotnikov <constantine.plotnikov@gmail.com> * Copyright (C) 2009, Google Inc. * Copyright (C) 2009, 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 static java.nio.charset.StandardCharsets.UTF_8; import java.io.FileNotFoundException; import java.io.IOException; import java.text.MessageFormat; import org.eclipse.jgit.errors.ConfigInvalidException; import org.eclipse.jgit.errors.IncorrectObjectTypeException; import org.eclipse.jgit.errors.MissingObjectException; import org.eclipse.jgit.internal.JGitText; import org.eclipse.jgit.revwalk.RevCommit; import org.eclipse.jgit.revwalk.RevTree; import org.eclipse.jgit.revwalk.RevWalk; import org.eclipse.jgit.treewalk.TreeWalk; import org.eclipse.jgit.util.RawParseUtils; /** * Configuration file based on the blobs stored in the repository. * * This implementation currently only provides reading support, and is primarily * useful for supporting the {@code .gitmodules} file. */ public class BlobBasedConfig extends Config { /** * Parse a configuration from a byte array. * * @param base * the base configuration file * @param blob * the byte array, should be UTF-8 encoded text. * @throws org.eclipse.jgit.errors.ConfigInvalidException * the byte array is not a valid configuration format. */ public BlobBasedConfig(Config base, byte[] blob) throws ConfigInvalidException { super(base); final String decoded; if (isUtf8(blob)) { decoded = RawParseUtils.decode(UTF_8, blob, 3, blob.length); } else { decoded = RawParseUtils.decode(blob); } fromText(decoded); } /** * Load a configuration file from a blob. * * @param base * the base configuration file * @param db * the repository * @param objectId * the object identifier * @throws java.io.IOException * the blob cannot be read from the repository. * @throws org.eclipse.jgit.errors.ConfigInvalidException * the blob is not a valid configuration format. */ public BlobBasedConfig(Config base, Repository db, AnyObjectId objectId) throws IOException, ConfigInvalidException { this(base, read(db, objectId)); } private static byte[] read(Repository db, AnyObjectId blobId) throws MissingObjectException, IncorrectObjectTypeException, IOException { try (ObjectReader or = db.newObjectReader()) { return read(or, blobId); } } private static byte[] read(ObjectReader or, AnyObjectId blobId) throws MissingObjectException, IncorrectObjectTypeException, IOException { ObjectLoader loader = or.open(blobId, Constants.OBJ_BLOB); return loader.getCachedBytes(Integer.MAX_VALUE); } /** * Load a configuration file from a blob stored in a specific commit. * * @param base * the base configuration file * @param db * the repository containing the objects. * @param treeish * the tree (or commit) that contains the object * @param path * the path within the tree * @throws java.io.FileNotFoundException * the path does not exist in the commit's tree. * @throws java.io.IOException * the tree and/or blob cannot be accessed. * @throws org.eclipse.jgit.errors.ConfigInvalidException * the blob is not a valid configuration format. */ public BlobBasedConfig(Config base, Repository db, AnyObjectId treeish, String path) throws FileNotFoundException, IOException, ConfigInvalidException { this(base, read(db, treeish, path)); } private static byte[] read(Repository db, AnyObjectId treeish, String path) throws MissingObjectException, IncorrectObjectTypeException, IOException { try (ObjectReader or = db.newObjectReader()) { TreeWalk tree = TreeWalk.forPath(or, path, asTree(or, treeish)); if (tree == null) throw new FileNotFoundException(MessageFormat.format(JGitText.get().entryNotFoundByPath, path)); return read(or, tree.getObjectId(0)); } } private static AnyObjectId asTree(ObjectReader or, AnyObjectId treeish) throws MissingObjectException, IncorrectObjectTypeException, IOException { if (treeish instanceof RevTree) return treeish; if (treeish instanceof RevCommit && ((RevCommit) treeish).getTree() != null) return ((RevCommit) treeish).getTree(); try (RevWalk rw = new RevWalk(or)) { return rw.parseTree(treeish).getId(); } } }