001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.io.file;
019
020import java.io.IOException;
021import java.nio.file.DirectoryStream;
022import java.nio.file.FileVisitResult;
023import java.nio.file.Path;
024import java.util.Objects;
025
026/**
027 * A {@link java.nio.file.DirectoryStream.Filter DirectoryStream.Filter} that delegates to a {@link PathFilter}.
028 * <p>
029 * You pass this filter to {@link java.nio.file.Files#newDirectoryStream(Path, DirectoryStream.Filter)
030 * Files#newDirectoryStream(Path, DirectoryStream.Filter)}.
031 * </p>
032 *
033 * @since 2.9.0
034 */
035public class DirectoryStreamFilter implements DirectoryStream.Filter<Path> {
036
037    private final PathFilter pathFilter;
038
039    /**
040     * Constructs a new instance for the given path filter.
041     *
042     * @param pathFilter How to filter paths.
043     */
044    public DirectoryStreamFilter(final PathFilter pathFilter) {
045        // TODO Instead of NPE, we could map null to FalseFileFilter.
046        this.pathFilter = Objects.requireNonNull(pathFilter, "pathFilter");
047    }
048
049    @Override
050    public boolean accept(final Path path) throws IOException {
051        return pathFilter.accept(path, PathUtils.readBasicFileAttributes(path, PathUtils.EMPTY_LINK_OPTION_ARRAY)) == FileVisitResult.CONTINUE;
052    }
053
054    /**
055     * Gets the path filter.
056     *
057     * @return the path filter.
058     */
059    public PathFilter getPathFilter() {
060        return pathFilter;
061    }
062
063}