Java tutorial
/* * Syncany, www.syncany.org * Copyright (C) 2011-2015 Philipp C. Heckel <philipp.heckel@gmail.com> * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package org.syncany.operations.down.actions; import java.io.File; import java.io.FileNotFoundException; import java.io.IOException; import java.nio.file.Files; import java.nio.file.Path; import java.nio.file.Paths; import java.nio.file.attribute.DosFileAttributes; import java.nio.file.attribute.FileTime; import java.nio.file.attribute.PosixFilePermission; import java.nio.file.attribute.PosixFilePermissions; import java.text.SimpleDateFormat; import java.util.Date; import java.util.Set; import java.util.logging.Level; import java.util.logging.Logger; import org.apache.commons.io.FileExistsException; import org.apache.commons.io.FileUtils; import org.syncany.config.Config; import org.syncany.database.FileVersion; import org.syncany.database.FileVersion.FileType; import org.syncany.database.FileVersionComparator; import org.syncany.database.FileVersionComparator.FileChange; import org.syncany.database.FileVersionComparator.FileVersionComparison; import org.syncany.database.MemoryDatabase; import org.syncany.util.CollectionUtil; import org.syncany.util.EnvironmentUtil; import org.syncany.util.FileUtil; import org.syncany.util.NormalizedPath; /** * File system actions perform operations on the local disk -- creating, updating and * deleting files. Given an expected and a new {@link FileVersion} (namely file1 and file2), * the concrete implementation of a file system action performs an action on the file. * * <p>Implementations of this class treat file1 and file2 differently, depending on what * action they implement. * * @author Philipp C. Heckel <philipp.heckel@gmail.com> */ public abstract class FileSystemAction { protected static final Logger logger = Logger.getLogger(FileSystemAction.class.getSimpleName()); protected Config config; protected MemoryDatabase winningDatabase; protected FileVersion fileVersion1; protected FileVersion fileVersion2; protected FileVersionComparator fileVersionHelper; public FileSystemAction(Config config, MemoryDatabase winningDatabase, FileVersion file1, FileVersion file2) { this.config = config; this.winningDatabase = winningDatabase; this.fileVersion1 = file1; this.fileVersion2 = file2; this.fileVersionHelper = new FileVersionComparator(config.getLocalDir(), config.getChunker().getChecksumAlgorithm()); } public FileVersion getFile1() { return fileVersion1; } public FileVersion getFile2() { return fileVersion2; } public FileType getType() { if (fileVersion1 != null) { return fileVersion1.getType(); } else { return fileVersion2.getType(); } } protected void createSymlink(FileVersion reconstructedFileVersion) throws Exception { File reconstructedFileAtFinalLocation = getAbsolutePathFile(reconstructedFileVersion.getPath()); if (EnvironmentUtil.symlinksSupported()) { // Make directory if it does not exist File reconstructedFileParentDir = reconstructedFileAtFinalLocation.getParentFile(); if (!FileUtil.exists(reconstructedFileParentDir)) { logger.log(Level.INFO, " - Parent folder does not exist, creating " + reconstructedFileParentDir + " ..."); reconstructedFileParentDir.mkdirs(); } // Make link logger.log(Level.INFO, " - Creating symlink at " + reconstructedFileAtFinalLocation + " (target: " + reconstructedFileVersion.getLinkTarget() + ") ..."); FileUtil.createSymlink(reconstructedFileVersion.getLinkTarget(), reconstructedFileAtFinalLocation); } else { logger.log(Level.INFO, " - Skipping symlink (not supported) at " + reconstructedFileAtFinalLocation + " (target: " + reconstructedFileVersion.getLinkTarget() + ") ..."); } } protected void setLastModified(FileVersion reconstructedFileVersion) { File reconstructedFilesAtFinalLocation = getAbsolutePathFile(reconstructedFileVersion.getPath()); setLastModified(reconstructedFileVersion, reconstructedFilesAtFinalLocation); } protected void setLastModified(FileVersion reconstructedFileVersion, File reconstructedFilesAtFinalLocation) { // Using Files.setLastModifiedTime() instead of File.setLastModified() // due to pre-1970 issue. See #374 for details. try { FileTime newLastModifiedTime = FileTime .fromMillis(reconstructedFileVersion.getLastModified().getTime()); Files.setLastModifiedTime(reconstructedFilesAtFinalLocation.toPath(), newLastModifiedTime); } catch (IOException e) { logger.log(Level.WARNING, "Warning: Could not set last modified date for file " + reconstructedFilesAtFinalLocation + "; Ignoring error.", e); } } protected void moveToConflictFile(FileVersion targetFileVersion) throws IOException { NormalizedPath targetConflictingFile = new NormalizedPath(config.getLocalDir(), targetFileVersion.getPath()); moveToConflictFile(targetConflictingFile); } protected void moveToConflictFile(NormalizedPath conflictingPath) throws IOException { if (!FileUtil.exists(conflictingPath.toFile())) { logger.log(Level.INFO, " - Creation of conflict file not necessary. Locally conflicting file vanished from " + conflictingPath); return; } int attempts = 0; while (attempts++ < 10) { NormalizedPath conflictedCopyPath = null; try { conflictedCopyPath = findConflictFilename(conflictingPath); logger.log(Level.INFO, " - Local version conflicts, moving local file " + conflictingPath + " to " + conflictedCopyPath + " ..."); if (conflictingPath.toFile().isDirectory()) { FileUtils.moveDirectory(conflictingPath.toFile(), conflictedCopyPath.toFile()); } else { FileUtils.moveFile(conflictingPath.toFile(), conflictedCopyPath.toFile()); } // Success! break; } catch (FileExistsException e) { logger.log(Level.SEVERE, " - Cannot create conflict file; attempt = " + attempts + " for file: " + conflictedCopyPath, e); } catch (FileNotFoundException e) { logger.log(Level.INFO, " - Conflict file vanished. Don't care!", e); } catch (Exception e) { throw new RuntimeException("What to do here?", e); } } } protected File moveFileToFinalLocation(File reconstructedFileInCache, FileVersion targetFileVersion) throws IOException { NormalizedPath originalPath = new NormalizedPath(config.getLocalDir(), targetFileVersion.getPath()); NormalizedPath targetPath = originalPath; try { // Clean filename if (targetPath.hasIllegalChars()) { targetPath = targetPath.toCreatable("filename conflict", true); } // Try creating folder createFolder(targetPath.getParent()); } catch (Exception e) { throw new RuntimeException("What to do here?!"); } // Try moving file to final destination try { FileUtils.moveFile(reconstructedFileInCache, targetPath.toFile()); } catch (FileExistsException e) { logger.log(Level.FINE, "File already existed", e); moveToConflictFile(targetPath); } catch (Exception e) { throw new RuntimeException("What to do here?!"); } return targetPath.toFile(); } protected void createFolder(NormalizedPath targetDir) throws Exception { if (!FileUtil.exists(targetDir.toFile())) { logger.log(Level.INFO, " - Creating folder at " + targetDir.toFile() + " ..."); boolean targetDirCreated = targetDir.toFile().mkdirs(); if (!targetDirCreated) { throw new Exception("Cannot create target dir: " + targetDir); } } else if (!FileUtil.isDirectory(targetDir.toFile())) { logger.log(Level.INFO, " - Expected a folder at " + targetDir.toFile() + " ..."); moveToConflictFile(targetDir); } } private NormalizedPath findConflictFilename(NormalizedPath conflictingPath) throws Exception { String conflictUserName = (config.getDisplayName() != null) ? config.getDisplayName() : config.getMachineName(); boolean conflictUserNameEndsWithS = conflictUserName.endsWith("s"); String conflictDate = new SimpleDateFormat("d MMM yy, h-mm a").format(new Date()); String conflictFilenameSuffix; if (conflictUserNameEndsWithS) { conflictFilenameSuffix = String.format("%s' conflicted copy, %s", conflictUserName, conflictDate); } else { conflictFilenameSuffix = String.format("%s's conflicted copy, %s", conflictUserName, conflictDate); } return conflictingPath.withSuffix(conflictFilenameSuffix, false); } protected void setFileAttributes(FileVersion reconstructedFileVersion) throws IOException { File reconstructedFilesAtFinalLocation = getAbsolutePathFile(reconstructedFileVersion.getPath()); setFileAttributes(reconstructedFileVersion, reconstructedFilesAtFinalLocation); } protected void setFileAttributes(FileVersion reconstructedFileVersion, File reconstructedFilesAtFinalLocation) throws IOException { if (EnvironmentUtil.isWindows()) { if (reconstructedFileVersion.getDosAttributes() != null) { logger.log(Level.INFO, " - Setting DOS attributes: " + reconstructedFileVersion.getDosAttributes() + " ..."); DosFileAttributes dosAttrs = FileUtil .dosAttrsFromString(reconstructedFileVersion.getDosAttributes()); Path filePath = Paths.get(reconstructedFilesAtFinalLocation.getAbsolutePath()); try { Files.setAttribute(filePath, "dos:readonly", dosAttrs.isReadOnly()); Files.setAttribute(filePath, "dos:hidden", dosAttrs.isHidden()); Files.setAttribute(filePath, "dos:archive", dosAttrs.isArchive()); Files.setAttribute(filePath, "dos:system", dosAttrs.isSystem()); } catch (IOException e) { logger.log(Level.WARNING, " - WARNING: Cannot set file attributes for " + filePath, e); } } } else if (EnvironmentUtil.isUnixLikeOperatingSystem()) { if (reconstructedFileVersion.getPosixPermissions() != null) { logger.log(Level.INFO, " - Setting POSIX permissions: " + reconstructedFileVersion.getPosixPermissions() + " ..."); Set<PosixFilePermission> posixPerms = PosixFilePermissions .fromString(reconstructedFileVersion.getPosixPermissions()); Path filePath = Paths.get(reconstructedFilesAtFinalLocation.getAbsolutePath()); try { Files.setPosixFilePermissions(filePath, posixPerms); } catch (IOException e) { logger.log(Level.WARNING, " - WARNING: Cannot set file permissions for " + filePath, e); } } } } protected boolean fileAsExpected(FileVersion expectedLocalFileVersion) { return fileAsExpected(expectedLocalFileVersion, new FileChange[] {}); } protected boolean fileAsExpected(FileVersion expectedLocalFileVersion, FileChange... allowedFileChanges) { FileVersionComparison fileVersionComparison = fileChanges(expectedLocalFileVersion); if (fileVersionComparison.areEqual()) { return true; } else if (allowedFileChanges.length > 0) { return CollectionUtil.containsOnly(fileVersionComparison.getFileChanges(), allowedFileChanges); } else { return false; } } protected FileVersionComparison fileChanges(FileVersion expectedLocalFileVersion) { File actualLocalFile = getAbsolutePathFile(expectedLocalFileVersion.getPath()); FileVersionComparison fileVersionComparison = fileVersionHelper.compare(expectedLocalFileVersion, actualLocalFile, true); return fileVersionComparison; } protected boolean fileExists(FileVersion expectedLocalFileVersion) { File actualLocalFile = getAbsolutePathFile(expectedLocalFileVersion.getPath()); return FileUtil.exists(actualLocalFile); } protected void deleteFile(FileVersion deleteFileVersion) { File fromFileOnDisk = getAbsolutePathFile(deleteFileVersion.getPath()); fromFileOnDisk.delete(); } protected File getAbsolutePathFile(String relativePath) { return new File(config.getLocalDir(), relativePath); // TODO [medium] This does not work for 'some\file' on windows! } public abstract FileSystemActionResult execute() throws Exception; }