Java File Extension Name Get getFileExtension(final File file)

Description

Gets the extension of a filename.

License

Apache License

Parameter

Parameter	Description
file	he file to retrieve the extension of.

Return

the extension of the file or an empty string if none exists.

Declaration

public static String getFileExtension(final File file) 

Method Source Code

//package com.java2s;
/*//from w w w.ja v  a2s  .co m
 * Copyright (c) 2016, The Dattack team (http://www.dattack.com)
 * Licensed 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.
 */

import java.io.File;

public class Main {
    /**
     * Gets the extension of a filename.
     *
     * @param file
     *            he file to retrieve the extension of.
     * @return the extension of the file or an empty string if none exists.
     */
    public static String getFileExtension(final File file) {

        if (file == null) {
            throw new IllegalArgumentException("Unable to get the file extension from 'null'");
        }

        final String fileName = file.getName();
        final int lastIndexOfDot = fileName.lastIndexOf('.');
        if (lastIndexOfDot > 0) {
            return fileName.substring(lastIndexOfDot + 1);
        }
        return "";
    }
}

Related

1. getFileExtension(File file)
2. getFileExtension(File file)
3. getFileExtension(File file, boolean includeDot)
4. getFileExtension(File file, boolean withDot)
5. getFileExtension(final File aFile)
6. getFileExtension(final File file)
7. getFileExtension(final String file)
8. getFileExtension(final String fullName)
9. getFileExtension(String file)