Java tutorial
/* * Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.nio.file; import java.nio.file.attribute.BasicFileAttributes; import java.io.IOException; import java.util.Objects; /** * A simple visitor of files with default behavior to visit all files and to * re-throw I/O errors. * * <p> Methods in this class may be overridden subject to their general contract. * * @param <T> The type of reference to the files * * @since 1.7 */ public class SimpleFileVisitor<T> implements FileVisitor<T> { /** * Initializes a new instance of this class. */ protected SimpleFileVisitor() { } /** * Invoked for a directory before entries in the directory are visited. * * <p> Unless overridden, this method returns {@link FileVisitResult#CONTINUE * CONTINUE}. */ @Override public FileVisitResult preVisitDirectory(T dir, BasicFileAttributes attrs) throws IOException { Objects.requireNonNull(dir); Objects.requireNonNull(attrs); return FileVisitResult.CONTINUE; } /** * Invoked for a file in a directory. * * <p> Unless overridden, this method returns {@link FileVisitResult#CONTINUE * CONTINUE}. */ @Override public FileVisitResult visitFile(T file, BasicFileAttributes attrs) throws IOException { Objects.requireNonNull(file); Objects.requireNonNull(attrs); return FileVisitResult.CONTINUE; } /** * Invoked for a file that could not be visited. * * <p> Unless overridden, this method re-throws the I/O exception that prevented * the file from being visited. */ @Override public FileVisitResult visitFileFailed(T file, IOException exc) throws IOException { Objects.requireNonNull(file); throw exc; } /** * Invoked for a directory after entries in the directory, and all of their * descendants, have been visited. * * <p> Unless overridden, this method returns {@link FileVisitResult#CONTINUE * CONTINUE} if the directory iteration completes without an I/O exception; * otherwise this method re-throws the I/O exception that caused the iteration * of the directory to terminate prematurely. */ @Override public FileVisitResult postVisitDirectory(T dir, IOException exc) throws IOException { Objects.requireNonNull(dir); if (exc != null) throw exc; return FileVisitResult.CONTINUE; } }