Java tutorial
/** * DataCleaner (community edition) * Copyright (C) 2014 Neopost - Customer Information Management * * This copyrighted material is made available to anyone wishing to use, modify, * copy, or redistribute it subject to the terms and conditions of the GNU * Lesser General Public License, as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License * for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this distribution; if not, write to: * Free Software Foundation, Inc. * 51 Franklin Street, Fifth Floor * Boston, MA 02110-1301 USA */ package org.datacleaner.user.upgrade; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.URL; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.Comparator; import java.util.List; import org.apache.commons.vfs2.AllFileSelector; import org.apache.commons.vfs2.FileDepthSelector; import org.apache.commons.vfs2.FileObject; import org.apache.commons.vfs2.FileSystemException; import org.apache.commons.vfs2.FileType; import org.apache.metamodel.util.FileHelper; import org.datacleaner.Version; import org.datacleaner.VersionComparator; import org.datacleaner.user.DemoConfiguration; import org.datacleaner.util.ResourceManager; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Checks if there is DataCleanerHome set up for previous versions of * DataCleaner and upgrades. */ public final class DataCleanerHomeUpgrader { private static final Logger logger = LoggerFactory.getLogger(DataCleanerHomeUpgrader.class); private static final List<String> candidateBlacklist = Arrays.asList("log", Version.UNKNOWN_VERSION); /** * Finds a folder to upgrade from based on the "newFolder" parameter - * upgrades are performed only within the same major version. * * @param newFolder * The folder we want to upgrade to (the new version) * @return true if upgrade was successful, false otherwise */ public boolean upgrade(FileObject newFolder) { try { if (newFolder.getChildren().length != 0) { // if the folder is not new then we don't want to touch it return false; } final FileObject upgradeFromFolderCandidate = findUpgradeCandidate(newFolder); if (upgradeFromFolderCandidate == null) { logger.info("Did not find a suitable upgrade candidate"); return false; } logger.info("Upgrading DATACLEANER_HOME from : {}", upgradeFromFolderCandidate); newFolder.copyFrom(upgradeFromFolderCandidate, new AllFileSelector()); // special handling of userpreferences.dat - we only want to keep // the good parts ;-) final UserPreferencesUpgrader userPreferencesUpgrader = new UserPreferencesUpgrader(newFolder); userPreferencesUpgrader.upgrade(); // Overwrite example jobs final List<String> allFilePaths = DemoConfiguration.getAllFilePaths(); for (String filePath : allFilePaths) { overwriteFileWithDefaults(newFolder, filePath); } return true; } catch (FileSystemException e) { logger.warn("Exception occured during upgrading: {}", e); return false; } } private FileObject findUpgradeCandidate(FileObject target) throws FileSystemException { FileObject parentFolder = target.getParent(); List<FileObject> versionFolders = new ArrayList<>(); FileObject[] allFoldersInParent = parentFolder.findFiles(new FileDepthSelector(1, 1)); for (FileObject folderInParent : allFoldersInParent) { final String folderInParentName = folderInParent.getName().getBaseName(); if (folderInParent.getType().equals(FileType.FOLDER) && (!folderInParentName.equals(target.getName().getBaseName())) && (!candidateBlacklist.contains(folderInParentName))) { versionFolders.add(folderInParent); } } List<FileObject> validatedVersionFolders = validateVersionFolders(versionFolders); if (!validatedVersionFolders.isEmpty()) { List<String> versions = new ArrayList<>(); for (FileObject validatedVersionFolder : validatedVersionFolders) { String baseName = validatedVersionFolder.getName().getBaseName(); versions.add(baseName); } final Comparator<String> comp = new VersionComparator(); String latestVersion = Collections.max(versions, comp); FileObject latestVersionFolder = null; for (FileObject validatedVersionFolder : validatedVersionFolders) { if (validatedVersionFolder.getName().getBaseName().equals(latestVersion)) { latestVersionFolder = validatedVersionFolder; } } return latestVersionFolder; } else { return null; } } private static List<FileObject> validateVersionFolders(List<FileObject> versionFolders) { List<FileObject> validatedVersionFolders = new ArrayList<>(); Integer currentMajorVersion = Version.getMajorVersion(); if (currentMajorVersion == null) { return validatedVersionFolders; } for (FileObject versionFolder : versionFolders) { String baseName = versionFolder.getName().getBaseName(); String[] versionParts = baseName.split("\\."); try { int majorVersion = Integer.parseInt(versionParts[0]); if (majorVersion != currentMajorVersion) { continue; } } catch (NumberFormatException e) { continue; } boolean validated = true; for (String versionPart : versionParts) { if (versionPart.endsWith("-SNAPSHOT")) { versionPart = versionPart.substring(0, versionPart.lastIndexOf("-SNAPSHOT")); } try { Integer.parseInt(versionPart); } catch (NumberFormatException e) { logger.warn( "Found a version folder in home directory ({}) with a part that could not be parsed to an integer: {} Removing this folder from potential upgrade candidates.", baseName, versionPart); validated = false; } } if (validated) { validatedVersionFolders.add(versionFolder); } } return validatedVersionFolders; } private static FileObject overwriteFileWithDefaults(FileObject targetDirectory, String targetFilename) throws FileSystemException { FileObject file = targetDirectory.resolveFile(targetFilename); FileObject parentFile = file.getParent(); if (!parentFile.exists()) { parentFile.createFolder(); } final ResourceManager resourceManager = ResourceManager.get(); final URL url = resourceManager.getUrl("datacleaner-home/" + targetFilename); if (url == null) { return null; } InputStream in = null; OutputStream out = null; try { in = url.openStream(); out = file.getContent().getOutputStream(); FileHelper.copy(in, out); } catch (IOException e) { throw new IllegalArgumentException(e); } finally { FileHelper.safeClose(in, out); } return file; } }