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 019package org.apache.hadoop.fs; 020 021import java.util.regex.PatternSyntaxException; 022import java.io.IOException; 023 024import org.apache.hadoop.classification.InterfaceAudience; 025import org.apache.hadoop.classification.InterfaceStability; 026 027/** 028 * A filter for POSIX glob pattern with brace expansions. 029 */ 030@InterfaceAudience.Public 031@InterfaceStability.Evolving 032public 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}