Java URL Relative getRelativeURL(File base, File file)

Description

returns the relative path of file to base.

License

Open Source License

Exception

Parameter	Description
IOException	if position of file is not relative to base

Declaration

public static String getRelativeURL(File base, File file) throws IOException 

Method Source Code

//package com.java2s;
/*--------------------------------------------------------------------------*
 | Copyright (C) 2006 Christopher Kohlhaas                                  |
 |                                                                          |
 | This program is free software; you can redistribute it and/or modify     |
 | it under the terms of the GNU General Public License as published by the |
 | Free Software Foundation. A copy of the license has been included with   |
 | these distribution in the COPYING file, if not go to www.fsf.org         |
 |                                                                          |
 | As a special exception, you are granted the permissions to link this     |
 | program with every library, which license fulfills the Open Source       |
 | Definition as published by the Open Source Initiative (OSI).             |
 *--------------------------------------------------------------------------*/

import java.io.File;

import java.io.IOException;

public class Main {
    /** returns the relative path of file to base.
     * same as {@link #getRelativePath(File, File)} but replaces windows-plattform-specific
     * file separator <code>\</code> with <code>/</code>
     * @throws IOException if position of file is not relative  to base
     *///from  w  ww.  j a v  a2  s .  c om
    public static String getRelativeURL(File base, File file) throws IOException {
        StringBuffer result = new StringBuffer(getRelativePath(base, file));
        for (int i = 0; i < result.length(); i++) {
            if (result.charAt(i) == '\\')
                result.setCharAt(i, '/');
        }
        return result.toString();
    }

    /** returns the relative path of file to base.
     * @throws IOException if position of file is not relative  to base
    */
    public static String getRelativePath(File base, File file) throws IOException {
        String filePath = file.getAbsoluteFile().getCanonicalPath();
        String basePath = base.getAbsoluteFile().getCanonicalPath();
        int start = filePath.indexOf(basePath);
        if (start != 0)
            throw new IOException(basePath + " not ancestor of " + filePath);
        return filePath.substring(basePath.length());
    }
}

Related

1. getRelativeNameOrURL(File baseDir, File file)
2. getRelativeURI(File fromFile, File toFile)
3. getRelativeUrl(File basePath, File targetPath)
4. getRelativeURLAsStream(Class clazz, String fileName)