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/*
* 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.vfs2.filter;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.apache.commons.vfs2.FileFilter;
import org.apache.commons.vfs2.FileSelectInfo;
/**
* Filters file names for a certain prefix.
*
* For example, to print all files and directories in the current directory
* whose name starts with a .:
*
*
*
* FileSystemManager fsManager = VFS.getManager();
* FileObject dir = fsManager.toFileObject(new File("."));
* FileObject[] files = dir.findFiles(new FileFilterSelector(new PrefixFileFilter(".")));
* for (int i = 0; i < files.length; i++) {
* System.out.println(files[i]);
* }
*
*
* @author This code was originally ported from Apache Commons IO File Filter
* @see "http://commons.apache.org/proper/commons-io/"
* @since 2.4
*/
public class PrefixFileFilter implements FileFilter, Serializable {
private static final long serialVersionUID = 1L;
/** Whether the comparison is case sensitive. */
private final IOCase caseSensitivity;
/** The file name prefixes to search for. */
private final List prefixes;
/**
* Constructs a new Prefix file filter for a list of prefixes.
*
* @param prefixes the prefixes to allow, must not be null
*/
public PrefixFileFilter(final List prefixes) {
this(IOCase.SENSITIVE, prefixes);
}
/**
* Constructs a new Prefix file filter for a list of prefixes specifying
* case-sensitivity.
*
* @param caseSensitivity how to handle case sensitivity, null means
* case-sensitive
* @param prefixes the prefixes to allow, must not be null
*/
public PrefixFileFilter(final IOCase caseSensitivity, final List prefixes) {
if (prefixes == null) {
throw new IllegalArgumentException("The list of prefixes must not be null");
}
this.prefixes = new ArrayList<>(prefixes);
this.caseSensitivity = caseSensitivity == null ? IOCase.SENSITIVE : caseSensitivity;
}
/**
* 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
*/
public PrefixFileFilter(final String... prefixes) {
this(IOCase.SENSITIVE, prefixes);
}
/**
* Constructs a new Prefix file filter for any of an array of prefixes
* specifying case-sensitivity.
*
* @param prefixes the prefixes to allow, must not be null
* @param caseSensitivity how to handle case sensitivity, null means
* case-sensitive
*/
public PrefixFileFilter(final IOCase caseSensitivity, final String... prefixes) {
if (prefixes == null) {
throw new IllegalArgumentException("The array of prefixes must not be null");
}
this.prefixes = new ArrayList<>(Arrays.asList(prefixes));
this.caseSensitivity = caseSensitivity == null ? IOCase.SENSITIVE : caseSensitivity;
}
/**
* Checks to see if the file name starts with the prefix.
*
* @param fileInfo the File to check
*
* @return true if the file name starts with one of our prefixes
*/
@Override
public boolean accept(final FileSelectInfo fileInfo) {
final String name = fileInfo.getFile().getName().getBaseName();
for (final String prefix : this.prefixes) {
if (caseSensitivity.checkStartsWith(name, prefix)) {
return true;
}
}
return false;
}
/**
* Provide a String representation of this file filter.
*
* @return a String representation
*/
@Override
public String toString() {
final StringBuilder buffer = new StringBuilder();
buffer.append(super.toString());
buffer.append("(");
if (prefixes != null) {
for (int i = 0; i < prefixes.size(); i++) {
if (i > 0) {
buffer.append(",");
}
buffer.append(prefixes.get(i));
}
}
buffer.append(")");
return buffer.toString();
}
}