    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 */
    017package org.apache.commons.io.filefilter;
    018
    019import java.io.File;
    020import java.io.Serializable;
    021import java.nio.file.FileVisitResult;
    022import java.nio.file.Path;
    023import java.nio.file.attribute.BasicFileAttributes;
    024import java.util.List;
    025import java.util.Objects;
    026import java.util.stream.Stream;
    027
    028import org.apache.commons.io.IOCase;
    029import org.apache.commons.io.file.PathUtils;
    030
    031/**
    032 * Filters files based on the suffix (what the file name ends with).
    033 * This is used in retrieving all the files of a particular type.
    034 * <p>
    035 * For example, to retrieve and print all {@code *.java} files
    036 * in the current directory:
    037 * </p>
    038 * <h2>Using Classic IO</h2>
    039 * <pre>
    040 * File dir = FileUtils.current();
    041 * String[] files = dir.list(new SuffixFileFilter(".java"));
    042 * for (String file : files) {
    043 *     System.out.println(file);
    044 * }
    045 * </pre>
    046 *
    047 * <h2>Using NIO</h2>
    048 * <pre>
    049 * final Path dir = PathUtils.current();
    050 * final AccumulatorPathVisitor visitor = AccumulatorPathVisitor.withLongCounters(new SuffixFileFilter(".java"));
    051 * //
    052 * // Walk one directory
    053 * Files.<strong>walkFileTree</strong>(dir, Collections.emptySet(), 1, visitor);
    054 * System.out.println(visitor.getPathCounters());
    055 * System.out.println(visitor.getFileList());
    056 * //
    057 * visitor.getPathCounters().reset();
    058 * //
    059 * // Walk directory tree
    060 * Files.<strong>walkFileTree</strong>(dir, visitor);
    061 * System.out.println(visitor.getPathCounters());
    062 * System.out.println(visitor.getDirList());
    063 * System.out.println(visitor.getFileList());
    064 * </pre>
    065 * <h2>Deprecating Serialization</h2>
    066 * <p>
    067 * <em>Serialization is deprecated and will be removed in 3.0.</em>
    068 * </p>
    069 *
    070 * @since 1.0
    071 * @see FileFilterUtils#suffixFileFilter(String)
    072 * @see FileFilterUtils#suffixFileFilter(String, IOCase)
    073 */
    074public class SuffixFileFilter extends AbstractFileFilter implements Serializable {
    075
    076    private static final long serialVersionUID = -3389157631240246157L;
    077
    078    /** The file name suffixes to search for */
    079    private final String[] suffixes;
    080
    081    /** Whether the comparison is case-sensitive. */
    082    private final IOCase ioCase;
    083
    084    /**
    085     * Constructs a new Suffix file filter for a list of suffixes.
    086     *
    087     * @param suffixes  the suffixes to allow, must not be null
    088     * @throws IllegalArgumentException if the suffix list is null
    089     * @throws ClassCastException if the list does not contain Strings
    090     */
    091    public SuffixFileFilter(final List<String> suffixes) {
    092        this(suffixes, IOCase.SENSITIVE);
    093    }
    094
    095    /**
    096     * Constructs a new Suffix file filter for a list of suffixes
    097     * specifying case-sensitivity.
    098     *
    099     * @param suffixes  the suffixes to allow, must not be null
    100     * @param ioCase  how to handle case sensitivity, null means case-sensitive
    101     * @throws IllegalArgumentException if the suffix list is null
    102     * @throws ClassCastException if the list does not contain Strings
    103     * @since 1.4
    104     */
    105    public SuffixFileFilter(final List<String> suffixes, final IOCase ioCase) {
    106        Objects.requireNonNull(suffixes, "suffixes");
    107        this.suffixes = suffixes.toArray(EMPTY_STRING_ARRAY);
    108        this.ioCase = IOCase.value(ioCase, IOCase.SENSITIVE);
    109    }
    110
    111    /**
    112     * Constructs a new Suffix file filter for a single extension.
    113     *
    114     * @param suffix  the suffix to allow, must not be null
    115     * @throws IllegalArgumentException if the suffix is null
    116     */
    117    public SuffixFileFilter(final String suffix) {
    118        this(suffix, IOCase.SENSITIVE);
    119    }
    120
    121    /**
    122     * Constructs a new Suffix file filter for an array of suffixes.
    123     * <p>
    124     * The array is not cloned, so could be changed after constructing the
    125     * instance. This would be inadvisable however.
    126     * </p>
    127     *
    128     * @param suffixes  the suffixes to allow, must not be null
    129     * @throws NullPointerException if the suffix array is null
    130     */
    131    public SuffixFileFilter(final String... suffixes) {
    132        this(suffixes, IOCase.SENSITIVE);
    133    }
    134
    135    /**
    136     * Constructs a new Suffix file filter for a single extension
    137     * specifying case-sensitivity.
    138     *
    139     * @param suffix  the suffix to allow, must not be null
    140     * @param ioCase  how to handle case sensitivity, null means case-sensitive
    141     * @throws NullPointerException if the suffix is null
    142     * @since 1.4
    143     */
    144    public SuffixFileFilter(final String suffix, final IOCase ioCase) {
    145        Objects.requireNonNull(suffix, "suffix");
    146        this.suffixes = new String[] {suffix};
    147        this.ioCase = IOCase.value(ioCase, IOCase.SENSITIVE);
    148    }
    149
    150    /**
    151     * Constructs a new Suffix file filter for an array of suffixes
    152     * specifying case-sensitivity.
    153     *
    154     * @param suffixes  the suffixes to allow, must not be null
    155     * @param ioCase  how to handle case sensitivity, null means case-sensitive
    156     * @throws NullPointerException if the suffix array is null
    157     * @since 1.4
    158     */
    159    public SuffixFileFilter(final String[] suffixes, final IOCase ioCase) {
    160        Objects.requireNonNull(suffixes, "suffixes");
    161        this.suffixes = suffixes.clone();
    162        this.ioCase = IOCase.value(ioCase, IOCase.SENSITIVE);
    163    }
    164
    165    /**
    166     * Checks to see if the file name ends with the suffix.
    167     *
    168     * @param file  the File to check
    169     * @return true if the file name ends with one of our suffixes
    170     */
    171    @Override
    172    public boolean accept(final File file) {
    173        return accept(file.getName());
    174    }
    175
    176    /**
    177     * Checks to see if the file name ends with the suffix.
    178     *
    179     * @param file  the File directory
    180     * @param name  the file name
    181     * @return true if the file name ends with one of our suffixes
    182     */
    183    @Override
    184    public boolean accept(final File file, final String name) {
    185        return accept(name);
    186    }
    187
    188    /**
    189     * Checks to see if the file name ends with the suffix.
    190     *
    191     * @param path       the File to check
    192     * @param attributes the path's basic attributes (may be null).
    193     * @return true if the file name ends with one of our suffixes
    194     * @since 2.9.0
    195     */
    196    @Override
    197    public FileVisitResult accept(final Path path, final BasicFileAttributes attributes) {
    198        return toFileVisitResult(accept(PathUtils.getFileNameString(path)));
    199    }
    200
    201    private boolean accept(final String name) {
    202        return Stream.of(suffixes).anyMatch(suffix -> ioCase.checkEndsWith(name, suffix));
    203    }
    204
    205    /**
    206     * Provide a String representation of this file filter.
    207     *
    208     * @return a String representation
    209     */
    210    @Override
    211    public String toString() {
    212        final StringBuilder buffer = new StringBuilder();
    213        buffer.append(super.toString());
    214        buffer.append("(");
    215        append(suffixes, buffer);
    216        buffer.append(")");
    217        return buffer.toString();
    218    }
    219
    220}