Java tutorial
/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * See LICENSE.txt included in this distribution for the specific * language governing permissions and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at LICENSE.txt. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 2006, 2013, Oracle and/or its affiliates. All rights reserved. */ package org.opensolaris.opengrok.history; import java.io.BufferedReader; import java.io.File; import java.io.FileReader; import java.io.IOException; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import java.util.TreeMap; import java.util.logging.Level; import java.util.logging.Logger; import org.apache.commons.jrcs.rcs.Archive; import org.apache.commons.jrcs.rcs.Node; import org.apache.commons.jrcs.rcs.ParseException; import org.apache.commons.jrcs.rcs.Version; import org.opensolaris.opengrok.logger.LoggerFactory; /** * Virtualise RCS file as a reader, getting a specified version */ class RCSHistoryParser { private static final Logger LOGGER = LoggerFactory.getLogger(RCSHistoryParser.class); private static File readCVSRoot(File root, File CVSdir, String name) throws IOException { String cvsroot = readFirstLine(root); if (cvsroot == null) { return null; } if (cvsroot.charAt(0) != '/') { return null; } File repository = new File(CVSdir, "Repository"); String repo = readFirstLine(repository); String dir = cvsroot + File.separatorChar + repo; String filename = name + ",v"; File rcsFile = new File(dir, filename); if (!rcsFile.exists()) { File atticFile = new File(dir + File.separatorChar + "Attic", filename); if (atticFile.exists()) { rcsFile = atticFile; } } return rcsFile; } History parse(File file, Repository repos) throws HistoryException { try { return parseFile(file); } catch (IOException ioe) { throw new HistoryException(ioe); } } private History parseFile(File file) throws IOException { try { Archive archive = new Archive(getRCSFile(file).getPath()); Version ver = archive.getRevisionVersion(); Node n = archive.findNode(ver); n = n.root(); ArrayList<HistoryEntry> entries = new ArrayList<HistoryEntry>(); traverse(n, entries); History history = new History(); history.setHistoryEntries(entries); return history; } catch (ParseException pe) { throw RCSRepository.wrapInIOException("Could not parse file " + file.getPath(), pe); } } private void traverse(Node n, List<HistoryEntry> history) { if (n == null) { return; } traverse(n.getChild(), history); TreeMap<?, ?> brt = n.getBranches(); if (brt != null) { for (Iterator<?> i = brt.values().iterator(); i.hasNext();) { Node b = (Node) i.next(); traverse(b, history); } } if (!n.isGhost()) { HistoryEntry entry = new HistoryEntry(); entry.setRevision(n.getVersion().toString()); entry.setDate(n.getDate()); entry.setAuthor(n.getAuthor()); entry.setMessage(n.getLog()); entry.setActive(true); history.add(entry); } } protected static File getRCSFile(File file) { return getRCSFile(file.getParent(), file.getName()); } protected static File getRCSFile(String parent, String name) { File rcsDir = new File(parent, "RCS"); File rcsFile = new File(rcsDir, name + ",v"); if (rcsFile.exists()) { return rcsFile; } // not RCS, try CVS instead return getCVSFile(parent, name); } protected static File getCVSFile(String parent, String name) { try { File CVSdir = new File(parent, "CVS"); if (CVSdir.isDirectory() && CVSdir.canRead()) { File root = new File(CVSdir, "Root"); if (root.canRead()) { return readCVSRoot(root, CVSdir, name); } } } catch (Exception e) { LOGGER.log(Level.WARNING, "Failed to retrieve CVS file of parent: " + parent + ", name: " + name, e); } return null; } /** * Read the first line of a file. * @param file the file from which to read * @return the first line of the file, or {@code null} if the file is empty * @throws IOException if an I/O error occurs while reading the file */ private static String readFirstLine(File file) throws IOException { try (BufferedReader in = new BufferedReader(new FileReader(file))) { return in.readLine(); } } }