Java tutorial
/* blizzy's Backup - Easy to use personal file backup application Copyright (C) 2011-2012 Maik Schreiber 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 de.blizzy.backup.vfs; import java.io.BufferedInputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.nio.file.attribute.FileTime; import java.util.HashSet; import java.util.Set; import org.apache.commons.io.IOUtils; import org.apache.commons.lang3.StringUtils; import org.apache.commons.vfs2.FileContent; import org.apache.commons.vfs2.FileObject; import org.apache.commons.vfs2.FileSystemException; import org.apache.commons.vfs2.FileType; public abstract class RemoteFileOrFolder<L extends RemoteLocation> implements IFolder, IFile { private static final int BUFFER_SIZE = 128 * 1024; private String file; private L location; private FileObject fileObject; private FileContent fileContent; private Boolean isFolder; public RemoteFileOrFolder(String file, L location) { this.file = file; this.location = location; } @Override public String getName() { return StringUtils.substringAfterLast(file, "/"); //$NON-NLS-1$ } @Override public String getAbsolutePath() { return location.getProtocol() + "://" + location.getHost() + file; //$NON-NLS-1$ } @Override public IFolder getParentFolder() { if (!file.equals("/")) { //$NON-NLS-1$ String parentFolder = StringUtils.substringBeforeLast(file, "/"); //$NON-NLS-1$ if (StringUtils.isBlank(parentFolder)) { parentFolder = "/"; //$NON-NLS-1$ } return getFolder(parentFolder); } return null; } protected abstract IFolder getFolder(String folder); protected L getLocation() { return location; } @Override public boolean isHidden() { return getName().startsWith("."); //$NON-NLS-1$ } @Override public FileTime getCreationTime() { return null; } @Override public FileTime getLastModificationTime() throws IOException { FileContent content = getFileContent(); try { long lastModifiedTime = content.getLastModifiedTime(); return FileTime.fromMillis(lastModifiedTime); } catch (FileSystemException e) { return null; } } private FileObject getFileObject() throws IOException { if (fileObject == null) { IAction<FileObject> action = new IAction<FileObject>() { @Override public FileObject run() throws IOException { return location.resolveFile(file); } @Override public boolean canRetry(IOException e) { return location.canRetryAction(e); } }; fileObject = new ActionRunner<>(action, RemoteLocation.MAX_TRIES, location).run(); } return fileObject; } private FileContent getFileContent() throws IOException { if (fileContent == null) { final FileObject fileObject = getFileObject(); IAction<FileContent> action = new IAction<FileContent>() { @Override public FileContent run() throws IOException { return fileObject.getContent(); } @Override public boolean canRetry(IOException e) { return location.canRetryAction(e); } }; fileContent = new ActionRunner<>(action, RemoteLocation.MAX_TRIES, location).run(); } return fileContent; } @Override public boolean isFolder() throws IOException { if (isFolder == null) { isFolder = Boolean.valueOf(getFileObject().getType().equals(FileType.FOLDER)); } return isFolder.booleanValue(); } public void setIsFolder() { isFolder = Boolean.TRUE; } @Override public void copy(final IOutputStreamProvider outputStreamProvider) throws IOException { final FileContent fileContent = getFileContent(); IAction<Void> action = new IAction<Void>() { @Override public Void run() throws IOException { InputStream in = null; OutputStream out = null; try { in = new BufferedInputStream(fileContent.getInputStream(), BUFFER_SIZE); out = outputStreamProvider.getOutputStream(); IOUtils.copy(in, out); } finally { IOUtils.closeQuietly(in); IOUtils.closeQuietly(out); } return null; } @Override public boolean canRetry(IOException e) { return location.canRetryAction(e); } }; new ActionRunner<>(action, RemoteLocation.MAX_TRIES, location).run(); } @Override public long getLength() throws IOException { return getFileContent().getSize(); } @Override public Set<IFileSystemEntry> list() throws IOException { final FileObject fileObject = getFileObject(); IAction<Set<IFileSystemEntry>> action = new IAction<Set<IFileSystemEntry>>() { @Override public Set<IFileSystemEntry> run() throws IOException { Set<IFileSystemEntry> result = new HashSet<>(); for (FileObject child : fileObject.getChildren()) { result.add(getFileOrFolder(file + "/" + child.getName().getBaseName())); //$NON-NLS-1$ } return result; } @Override public boolean canRetry(IOException e) { return location.canRetryAction(e); } }; return new ActionRunner<>(action, RemoteLocation.MAX_TRIES, location).run(); } protected abstract IFolder getFileOrFolder(String file); @Override public int hashCode() { return file.hashCode(); } @Override public boolean equals(Object o) { if (o == this) { return true; } else if ((o != null) && o.getClass().equals(getClass())) { RemoteFileOrFolder<?> other = (RemoteFileOrFolder<?>) o; return other.file.equals(file); } return false; } }