/*
* 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.
*/
package org.apache.commons.io.filefilter;
import java.io.File;
import java.io.Serializable;
import java.util.regex.Pattern;
import org.apache.commons.io.IOCase;
/**
* Filters files using supplied regular expression(s).
* <p/>
* See java.util.regex.Pattern for regex matching rules
* <p/>
*
* <p/>
* e.g.
* <pre>
* File dir = new File(".");
* FileFilter fileFilter = new RegexFileFilter("^.*[tT]est(-\\d+)?\\.java$");
* File[] files = dir.listFiles(fileFilter);
* for (int i = 0; i < files.length; i++) {
* System.out.println(files[i]);
* }
* </pre>
*
* @author Oliver Siegmar
* @version $Revision: 659817 $
* @since Commons IO 1.4
*/
public class RegexFileFilter extends AbstractFileFilter implements Serializable {
/** The regular expression pattern that will be used to match filenames */
private final Pattern pattern;
/**
* Construct a new regular expression filter.
*
* @param pattern regular string expression to match
* @throws IllegalArgumentException if the pattern is null
*/
public RegexFileFilter(String pattern) {
if (pattern == null) {
throw new IllegalArgumentException("Pattern is missing");
}
this.pattern = Pattern.compile(pattern);
}
/**
* Construct a new regular expression filter with the specified flags case sensitivity.
*
* @param pattern regular string expression to match
* @param caseSensitivity how to handle case sensitivity, null means case-sensitive
* @throws IllegalArgumentException if the pattern is null
*/
public RegexFileFilter(String pattern, IOCase caseSensitivity) {
if (pattern == null) {
throw new IllegalArgumentException("Pattern is missing");
}
int flags = 0;
if (caseSensitivity != null && !caseSensitivity.isCaseSensitive()) {
flags = Pattern.CASE_INSENSITIVE;
}
this.pattern = Pattern.compile(pattern, flags);
}
/**
* Construct a new regular expression filter with the specified flags.
*
* @param pattern regular string expression to match
* @param flags pattern flags - e.g. {@link Pattern#CASE_INSENSITIVE}
* @throws IllegalArgumentException if the pattern is null
*/
public RegexFileFilter(String pattern, int flags) {
if (pattern == null) {
throw new IllegalArgumentException("Pattern is missing");
}
this.pattern = Pattern.compile(pattern, flags);
}
/**
* Construct a new regular expression filter for a compiled regular expression
*
* @param pattern regular expression to match
* @throws IllegalArgumentException if the pattern is null
*/
public RegexFileFilter(Pattern pattern) {
if (pattern == null) {
throw new IllegalArgumentException("Pattern is missing");
}
this.pattern = pattern;
}
/**
* Checks to see if the filename matches one of the regular expressions.
*
* @param dir the file directory
* @param name the filename
* @return true if the filename matches one of the regular expressions
*/
@Override
public boolean accept(File dir, String name) {
return (pattern.matcher(name).matches());
}
}
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