org.apache.commons.io.filefilter.PrefixFileFilter Maven / Gradle / Ivy
/*
* 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.util.List;
/**
* Filters filenames for a certain prefix.
*
* For example, to print all files and directories in the
* current directory whose name starts with Test:
*
*
* File dir = new File(".");
* String[] files = dir.list( new PrefixFileFilter("Test") );
* for ( int i = 0; i < files.length; i++ ) {
* System.out.println(files[i]);
* }
*
*
* @since Commons IO 1.0
* @version $Revision: 471628 $ $Date: 2006-11-06 05:06:45 +0100 (Mo, 06 Nov 2006) $
*
* @author Stephen Colebourne
* @author Federico Barbieri
* @author Serge Knystautas
* @author Peter Donald
*/
public class PrefixFileFilter extends AbstractFileFilter {
/** The filename prefixes to search for */
private String[] prefixes;
/**
* Constructs a new Prefix file filter for a single prefix.
*
* @param prefix the prefix to allow, must not be null
* @throws IllegalArgumentException if the prefix is null
*/
public PrefixFileFilter(String prefix) {
if (prefix == null) {
throw new IllegalArgumentException("The prefix must not be null");
}
this.prefixes = new String[] {prefix};
}
/**
* Constructs a new Prefix file filter for any of an array of prefixes.
*
* The array is not cloned, so could be changed after constructing the
* instance. This would be inadvisable however.
*
* @param prefixes the prefixes to allow, must not be null
* @throws IllegalArgumentException if the prefix array is null
*/
public PrefixFileFilter(String[] prefixes) {
if (prefixes == null) {
throw new IllegalArgumentException("The array of prefixes must not be null");
}
this.prefixes = prefixes;
}
/**
* Constructs a new Prefix file filter for a list of prefixes.
*
* @param prefixes the prefixes to allow, must not be null
* @throws IllegalArgumentException if the prefix list is null
* @throws ClassCastException if the list does not contain Strings
*/
public PrefixFileFilter(List prefixes) {
if (prefixes == null) {
throw new IllegalArgumentException("The list of prefixes must not be null");
}
this.prefixes = (String[]) prefixes.toArray(new String[prefixes.size()]);
}
/**
* Checks to see if the filename starts with the prefix.
*
* @param file the File to check
* @return true if the filename starts with one of our prefixes
*/
public boolean accept(File file) {
String name = file.getName();
for (int i = 0; i < this.prefixes.length; i++) {
if (name.startsWith(this.prefixes[i])) {
return true;
}
}
return false;
}
/**
* Checks to see if the filename starts with the prefix.
*
* @param file the File directory
* @param name the filename
* @return true if the filename starts with one of our prefixes
*/
public boolean accept(File file, String name) {
for (int i = 0; i < prefixes.length; i++) {
if (name.startsWith(prefixes[i])) {
return true;
}
}
return false;
}
}