1/*
2 * Copyright (c) 1994, 2003, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package sun.net.www.protocol.file;
27
28import java.net.InetAddress;
29import java.net.URLConnection;
30import java.net.URL;
31import java.net.Proxy;
32import java.net.MalformedURLException;
33import java.net.URLStreamHandler;
34import java.io.InputStream;
35import java.io.IOException;
36import sun.net.www.ParseUtil;
37import java.io.File;
38
39/**
40 * Open an file input stream given a URL.
41 * @author      James Gosling
42 */
43public class Handler extends URLStreamHandler {
44
45    private String getHost(URL url) {
46        String host = url.getHost();
47        if (host == null)
48            host = "";
49        return host;
50    }
51
52
53    protected void parseURL(URL u, String spec, int start, int limit) {
54        /*
55         * Ugly backwards compatibility. Flip any file separator
56         * characters to be forward slashes. This is a nop on Unix
57         * and "fixes" win32 file paths. According to RFC 2396,
58         * only forward slashes may be used to represent hierarchy
59         * separation in a URL but previous releases unfortunately
60         * performed this "fixup" behavior in the file URL parsing code
61         * rather than forcing this to be fixed in the caller of the URL
62         * class where it belongs. Since backslash is an "unwise"
63         * character that would normally be encoded if literally intended
64         * as a non-seperator character the damage of veering away from the
65         * specification is presumably limited.
66         */
67        super.parseURL(u, spec.replace(File.separatorChar, '/'), start, limit);
68    }
69
70    public synchronized URLConnection openConnection(URL u)
71        throws IOException {
72        return openConnection(u, null);
73    }
74
75    public synchronized URLConnection openConnection(URL u, Proxy p)
76           throws IOException {
77        String host = u.getHost();
78        if (host == null || host.equals("") || host.equals("~") ||
79            host.equalsIgnoreCase("localhost")) {
80            File file = new File(ParseUtil.decode(u.getPath()));
81            return createFileURLConnection(u, file);
82        }
83
84        /* If you reach here, it implies that you have a hostname
85           so attempt an ftp connection.
86         */
87        URLConnection uc;
88        URL ru;
89
90        try {
91            ru = new URL("ftp", host, u.getFile() +
92                             (u.getRef() == null ? "": "#" + u.getRef()));
93            if (p != null) {
94                uc = ru.openConnection(p);
95            } else {
96                uc = ru.openConnection();
97            }
98        } catch (IOException e) {
99            uc = null;
100        }
101        if (uc == null) {
102            throw new IOException("Unable to connect to: " +
103                                                       u.toExternalForm());
104        }
105        return uc;
106    }
107
108    // Template method to be overriden by Java Plug-in. [stanleyh]
109    //
110    protected URLConnection createFileURLConnection(URL u, File file)
111    {
112        return new FileURLConnection(u, file);
113    }
114
115    /**
116     * Compares the host components of two URLs.
117     * @param u1 the URL of the first host to compare
118     * @param u2 the URL of the second host to compare
119     * @return  <tt>true</tt> if and only if they
120     * are equal, <tt>false</tt> otherwise.
121     */
122    protected boolean hostsEqual(URL u1, URL u2) {
123        /*
124         * Special case for file: URLs
125         * per RFC 1738 no hostname is equivalent to 'localhost'
126         * i.e. file:///path is equal to file://localhost/path
127         */
128        String s1 = u1.getHost();
129        String s2 = u2.getHost();
130        if ("localhost".equalsIgnoreCase(s1) && ( s2 == null || "".equals(s2)))
131            return true;
132        if ("localhost".equalsIgnoreCase(s2) && ( s1 == null || "".equals(s1)))
133            return true;
134        return super.hostsEqual(u1, u2);
135    }
136}
137