Commons IO example source code file (NameFileFilter.java)

This example Commons IO source code file (NameFileFilter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons IO tags/keywords

abstractfilefilter, illegalargumentexception, io, iocase, iocase, namefilefilter, namefilefilter, override, serializable, string, string, stringbuilder, the, the, util

The Commons IO NameFileFilter.java source code

/*
 * 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.List;

import org.apache.commons.io.IOCase;

/**
 * Filters filenames for a certain name.
 * <p>
 * For example, to print all files and directories in the 
 * current directory whose name is <code>Test:
 *
 * <pre>
 * File dir = new File(".");
 * String[] files = dir.list( new NameFileFilter("Test") );
 * for ( int i = 0; i < files.length; i++ ) {
 *     System.out.println(files[i]);
 * }
 * </pre>
 *
 * @since Commons IO 1.0
 * @version $Revision: 1005099 $ $Date: 2010-10-06 17:13:01 +0100 (Wed, 06 Oct 2010) $
 * 
 * @author Stephen Colebourne
 * @author Federico Barbieri
 * @author Serge Knystautas
 * @author Peter Donald
 * @see FileFilterUtils#nameFileFilter(String)
 * @see FileFilterUtils#nameFileFilter(String, IOCase)
 */
public class NameFileFilter extends AbstractFileFilter implements Serializable {
    
    /** The filenames to search for */
    private final String[] names;
    /** Whether the comparison is case sensitive. */
    private final IOCase caseSensitivity;

    /**
     * Constructs a new case-sensitive name file filter for a single name.
     * 
     * @param name  the name to allow, must not be null
     * @throws IllegalArgumentException if the name is null
     */
    public NameFileFilter(String name) {
        this(name, null);
    }

    /**
     * Construct a new name file filter specifying case-sensitivity.
     *
     * @param name  the name to allow, must not be null
     * @param caseSensitivity  how to handle case sensitivity, null means case-sensitive
     * @throws IllegalArgumentException if the name is null
     */
    public NameFileFilter(String name, IOCase caseSensitivity) {
        if (name == null) {
            throw new IllegalArgumentException("The wildcard must not be null");
        }
        this.names = new String[] {name};
        this.caseSensitivity = (caseSensitivity == null ? IOCase.SENSITIVE : caseSensitivity);
    }

    /**
     * Constructs a new case-sensitive name file filter for an array of names.
     * <p>
     * The array is not cloned, so could be changed after constructing the
     * instance. This would be inadvisable however.
     * 
     * @param names  the names to allow, must not be null
     * @throws IllegalArgumentException if the names array is null
     */
    public NameFileFilter(String[] names) {
        this(names, null);
    }

    /**
     * Constructs a new name file filter for an array of names specifying case-sensitivity.
     * <p>
     * The array is not cloned, so could be changed after constructing the
     * instance. This would be inadvisable however.
     * 
     * @param names  the names to allow, must not be null
     * @param caseSensitivity  how to handle case sensitivity, null means case-sensitive
     * @throws IllegalArgumentException if the names array is null
     */
    public NameFileFilter(String[] names, IOCase caseSensitivity) {
        if (names == null) {
            throw new IllegalArgumentException("The array of names must not be null");
        }
        this.names = new String[names.length];
        System.arraycopy(names, 0, this.names, 0, names.length);
        this.caseSensitivity = (caseSensitivity == null ? IOCase.SENSITIVE : caseSensitivity);
    }

    /**
     * Constructs a new case-sensitive name file filter for a list of names.
     * 
     * @param names  the names to allow, must not be null
     * @throws IllegalArgumentException if the name list is null
     * @throws ClassCastException if the list does not contain Strings
     */
    public NameFileFilter(List<String> names) {
        this(names, null);
    }

    /**
     * Constructs a new name file filter for a list of names specifying case-sensitivity.
     * 
     * @param names  the names to allow, must not be null
     * @param caseSensitivity  how to handle case sensitivity, null means case-sensitive
     * @throws IllegalArgumentException if the name list is null
     * @throws ClassCastException if the list does not contain Strings
     */
    public NameFileFilter(List<String> names, IOCase caseSensitivity) {
        if (names == null) {
            throw new IllegalArgumentException("The list of names must not be null");
        }
        this.names = names.toArray(new String[names.size()]);
        this.caseSensitivity = (caseSensitivity == null ? IOCase.SENSITIVE : caseSensitivity);
    }

    //-----------------------------------------------------------------------
    /**
     * Checks to see if the filename matches.
     * 
     * @param file  the File to check
     * @return true if the filename matches
     */
    @Override
    public boolean accept(File file) {
        String name = file.getName();
        for (String name2 : this.names) {
            if (caseSensitivity.checkEquals(name, name2)) {
                return true;
            }
        }
        return false;
    }

    /**
     * Checks to see if the filename matches.
     * 
     * @param file  the File directory
     * @param name  the filename
     * @return true if the filename matches
     */
    @Override
    public boolean accept(File file, String name) {
        for (String name2 : names) {
            if (caseSensitivity.checkEquals(name, name2)) {
                return true;
            }
        }
        return false;
    }

    /**
     * Provide a String representaion of this file filter.
     *
     * @return a String representaion
     */
    @Override
    public String toString() {
        StringBuilder buffer = new StringBuilder();
        buffer.append(super.toString());
        buffer.append("(");
        if (names != null) {
            for (int i = 0; i < names.length; i++) {
                if (i > 0) {
                    buffer.append(",");
                }
                buffer.append(names[i]);
            }
        }
        buffer.append(")");
        return buffer.toString();
    }

}