/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
using System;
namespace Lucene.Net.Index
{
/// Filename filter that accept filenames and extensions only created by Lucene.
///
///
/// $rcs = ' $Id: Exp $ ' ;
///
public class IndexFileNameFilter
{
private static IndexFileNameFilter singleton = new IndexFileNameFilter();
private System.Collections.Hashtable extensions;
private System.Collections.Hashtable extensionsInCFS;
// Prevent instantiation.
private IndexFileNameFilter()
{
extensions = new System.Collections.Hashtable();
for (int i = 0; i < IndexFileNames.INDEX_EXTENSIONS.Length; i++)
{
extensions.Add(IndexFileNames.INDEX_EXTENSIONS[i], IndexFileNames.INDEX_EXTENSIONS[i]);
}
extensionsInCFS = new System.Collections.Hashtable();
for (int i = 0; i < IndexFileNames.INDEX_EXTENSIONS_IN_COMPOUND_FILE.Length; i++)
{
extensionsInCFS.Add(IndexFileNames.INDEX_EXTENSIONS_IN_COMPOUND_FILE[i], IndexFileNames.INDEX_EXTENSIONS_IN_COMPOUND_FILE[i]);
}
}
/* (non-Javadoc)
* @see java.io.FilenameFilter#accept(java.io.File, java.lang.String)
*/
public virtual bool Accept(System.IO.FileInfo dir, System.String name)
{
int i = name.LastIndexOf((System.Char) '.');
if (i != - 1)
{
System.String extension = name.Substring(1 + i);
if (extensions.Contains(extension))
{
return true;
}
else if (extension.StartsWith("f") && (new System.Text.RegularExpressions.Regex("f\\d+")).Match(extension).Success)
{
return true;
}
else if (extension.StartsWith("s") && (new System.Text.RegularExpressions.Regex("s\\d+")).Match(extension).Success)
{
return true;
}
}
else
{
if (name.Equals(IndexFileNames.DELETABLE))
return true;
else if (name.StartsWith(IndexFileNames.SEGMENTS))
return true;
}
return false;
}
/// Returns true if this is a file that would be contained
/// in a CFS file. This function should only be called on
/// files that pass the above "accept" (ie, are already
/// known to be a Lucene index file).
///
public virtual bool IsCFSFile(System.String name)
{
int i = name.LastIndexOf((System.Char) '.');
if (i != - 1)
{
System.String extension = name.Substring(1 + i);
if (extensionsInCFS.Contains(extension))
{
return true;
}
if (extension.StartsWith("f") && (new System.Text.RegularExpressions.Regex("f\\d+")).Match(extension).Success)
{
return true;
}
}
return false;
}
public static IndexFileNameFilter GetFilter()
{
return singleton;
}
}
}