001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019 package org.apache.hadoop.fs;
020
021 import java.util.regex.PatternSyntaxException;
022 import java.io.IOException;
023
024 import org.apache.hadoop.classification.InterfaceAudience;
025 import org.apache.hadoop.classification.InterfaceStability;
026
027 /**
028 * A filter for POSIX glob pattern with brace expansions.
029 */
030 @InterfaceAudience.Public
031 @InterfaceStability.Evolving
032 public class GlobFilter implements PathFilter {
033 private final static PathFilter DEFAULT_FILTER = new PathFilter() {
034 @Override
035 public boolean accept(Path file) {
036 return true;
037 }
038 };
039
040 private PathFilter userFilter = DEFAULT_FILTER;
041 private GlobPattern pattern;
042
043 /**
044 * Creates a glob filter with the specified file pattern.
045 *
046 * @param filePattern the file pattern.
047 * @throws IOException thrown if the file pattern is incorrect.
048 */
049 public GlobFilter(String filePattern) throws IOException {
050 init(filePattern, DEFAULT_FILTER);
051 }
052
053 /**
054 * Creates a glob filter with the specified file pattern and an user filter.
055 *
056 * @param filePattern the file pattern.
057 * @param filter user filter in addition to the glob pattern.
058 * @throws IOException thrown if the file pattern is incorrect.
059 */
060 public GlobFilter(String filePattern, PathFilter filter) throws IOException {
061 init(filePattern, filter);
062 }
063
064 void init(String filePattern, PathFilter filter) throws IOException {
065 try {
066 userFilter = filter;
067 pattern = new GlobPattern(filePattern);
068 }
069 catch (PatternSyntaxException e) {
070 // Existing code expects IOException startWith("Illegal file pattern")
071 throw new IOException("Illegal file pattern: "+ e.getMessage(), e);
072 }
073 }
074
075 boolean hasPattern() {
076 return pattern.hasWildcard();
077 }
078
079 @Override
080 public boolean accept(Path path) {
081 return pattern.matches(path.getName()) && userFilter.accept(path);
082 }
083 }