Android Path Relative Get getRelativeFileName(File file, File basedir)

Description

Gets a relative file from a filename against a base directory.

License

Open Source License

Parameter

Parameter	Description
filename	The filename to build a relative file from
basedir	The base directory for a relative filename

Exception

Parameter	Description
IOException	if the file paths cannot be canonicalized

Return

The relative file name, or null, if one input parameter was null

Declaration

public static String getRelativeFileName(File file, File basedir)
        throws IOException 

Method Source Code

//package com.java2s;
/*//from   w  w w. j  a  v  a  2 s. com
 * IzPack - Copyright 2001-2008 Julien Ponge, All Rights Reserved.
 *
 * http://izpack.org/
 * http://izpack.codehaus.org/
 *
 * Copyright 2005 Marc Eppelmann
 *
 * 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.*;

public class Main {
    /**
     * Gets a relative file from a filename against a base directory.
     * Enclosed '.' and '..' characters are resolved for all parameters.
     *
     * @param filename The filename to build a relative file from
     * @param basedir  The base directory for a relative filename
     * @return The relative file name, or null, if one input parameter was null
     * @throws IOException if the file paths cannot be canonicalized
     */
    public static String getRelativeFileName(File file, File basedir)
            throws IOException {
        String canonicalFilePath = file.getCanonicalPath();
        String canonicalBaseDirPath = basedir.getCanonicalPath();
        if (canonicalFilePath.startsWith(canonicalBaseDirPath)) {
            int length = canonicalBaseDirPath.length();
            if (length < canonicalFilePath.length()) {
                return canonicalFilePath.substring(length + 1);
            }
        }
        return null;
    }
}

Related

1. convertToRelativePath(String absolutePath, String relativeTo)
2. getPathRelativeTo(File fileChild, File fileRoot)
3. getRelativePath(File parent, File file)
4. getWindowsRelativePath(String basedir, String path)
5. relativePathFromBase(File file, File basedir)
6. getParentRelativeTo(File fileChild, File fileRoot)