jurt/com/sun/star/lib/util/UrlToFileMapper.java

   1 /* -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19 package com.sun.star.lib.util;
  20
  21 import java.io.File;
  22 import java.io.UnsupportedEncodingException;
  23 import java.net.URI;
  24 import java.net.URISyntaxException;
  25 import java.net.URL;
  26 import java.net.URLEncoder;
  27
  28 /**
  29  * Maps Java URL representations to File representations, on any Java version.
  30  *
  31  * This used to be used to do URL to File mapping in pre-Java1.4 days, but since
  32  * we now require Java 1.5, it is largely unnecessary.
  33  *
  34  * @since UDK 3.2.8
  35  */
  36 public final class UrlToFileMapper {
  37
  38     /**
  39      * Maps Java URL representations to File representations.
  40      *
  41      * @param url some URL, possibly null.
  42      * @return a corresponding File, or null on failure.
  43      */
  44     public static File mapUrlToFile(URL url) {
  45         if (url == null) {
  46             return null;
  47         } else {
  48             try {
  49                 // where encodedUrl is url.toString(), but since that may contain
  50                 // unsafe characters (e.g., space, " "), it is encoded, as otherwise
  51                 // the URI constructor might throw java.net.URISyntaxException (in
  52                 // Java 1.5, URL.toURI might be used instead).
  53                 String encodedUrl = encode(url.toString());
  54                 URI uri = new URI(encodedUrl);
  55                 try {
  56                     return new File(uri);
  57                 } catch (IllegalArgumentException e) {
  58                     return null;
  59                 }
  60             } catch (URISyntaxException ex) {
  61                 throw new RuntimeException(ex); // should never happen
  62             }
  63         }
  64     }
  65
  66     private static String encode(String url) {
  67         StringBuffer buf = new StringBuffer(url.length());
  68         for (int i = 0; i < url.length(); ++i) {
  69             char c = url.charAt(i);
  70             // The RFC 2732 <uric> characters: !$&'()*+,-./:;=?@[]_~ plus digits
  71             // and letters; additionally, do not encode % again.
  72             if (c >= 'a' && c <= 'z' || c >= '?' && c <= '['
  73                 || c >= '$' && c <= ';' || c == '!' || c == '=' || c == ']'
  74                 || c == '_' || c == '~')
  75             {
  76                 buf.append(c);
  77             } else if (c == ' ') {
  78                 buf.append("%20");
  79             } else {
  80                 try {
  81                     String enc = URLEncoder.encode(Character.toString(c), "UTF-8");
  82                     buf.append(enc);
  83                 } catch (UnsupportedEncodingException e) {
  84                     throw new RuntimeException(e); // should never happen
  85                 }
  86             }
  87         }
  88         return buf.toString();
  89     }
  90
  91     private UrlToFileMapper() {}
  92 }
  93
  94 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */