gcc/libjava/java/net/URLStreamHandler.java
2000-01-19 18:39:27 +00:00

157 lines
4.6 KiB
Java

// URLStreamHandler.java - Superclass of all stream protocol handlers.
/* Copyright (C) 1999 Red Hat, Inc.
This file is part of libgcj.
This software is copyrighted work licensed under the terms of the
Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
details. */
package java.net;
/**
* @author Warren Levy <warrenl@cygnus.com>
* @date March 4, 1999.
*/
/**
* Written using on-line Java Platform 1.2 API Specification, as well
* as "The Java Class Libraries", 2nd edition (Addison-Wesley, 1998).
* Status: Believed complete and correct.
*/
public abstract class URLStreamHandler
{
protected abstract URLConnection openConnection(URL u)
throws java.io.IOException;
protected void parseURL(URL u, String spec, int start, int limit)
{
String host = u.getHost();
int port = u.getPort();
String file = u.getFile();
/* TBD: The JDK 1.2 doc specifically says that limit is the position
* to stop parsing at and that it will be either the end of the string
* or the position of '#'; thus the doc infers that this method does
* not set the ref.
*/
if (spec.regionMatches (start, "//", 0, 2))
{
int hostEnd;
int colon;
start += 2;
int slash = spec.indexOf('/', start);
if (slash >= 0)
hostEnd = slash;
else
hostEnd = limit;
host = spec.substring (start, hostEnd);
// Look for optional port number. It is valid for the non-port
// part of the host name to be null (e.g. a URL "http://:80").
// TBD: JDK 1.2 in this case sets host to null rather than "";
// this is undocumented and likely an unintended side effect in 1.2
// so we'll be simple here and stick with "". Note that
// "http://" or "http:///" produce a "" host in JDK 1.2.
if ((colon = host.indexOf(':')) >= 0)
{
try
{
port = Integer.parseInt(host.substring(colon + 1));
}
catch (NumberFormatException e)
{
; // Ignore invalid port values; port is already set to u's
// port.
}
host = host.substring(0, colon);
}
file = null;
start = hostEnd;
}
else if (host == null)
host = "";
if (start < limit && spec.charAt(start) == '/')
{
// This is an absolute path name; ignore any file context.
file = spec.substring(start, limit);
}
else if (file == null || file.length() <= 0)
{
// No file context available; just spec for file.
file = "/" + spec.substring(start, limit);
}
else if (start < limit)
{
// Context is available, but only override it if there is a new file.
// FIXME: unsure to what extent `/` and File.separatorChar
// can mix in URLs. Ignore File.separatorChar for now.
file = file.substring(0, file.lastIndexOf('/'))
+ "/" + spec.substring(start, limit);
}
int index;
// Replace "/./" with "/". This probably isn't very efficient in
// the general case, but it's probably not bad most of the time.
while ((index = file.indexOf("/./")) >= 0)
file = file.substring(0, index) + file.substring(index + 2);
// Process "/../" correctly. This probably isn't very efficient in
// the general case, but it's probably not bad most of the time.
while ((index = file.indexOf("/../")) >= 0)
{
// Strip of the previous directory - if it exists.
int previous = file.lastIndexOf('/', index - 1);
if (previous >= 0)
file = file.substring(0, previous) + file.substring(index + 3);
else
file = file.substring(index + 3);
}
u.set(u.getProtocol(), host, port, file, u.getRef());
}
protected void setURL(URL u, String protocol, String host, int port,
String file, String ref)
{
u.set(protocol, host, port, file, ref);
}
protected String toExternalForm(URL u)
{
String resStr, host, file, ref;
int port;
resStr = u.getProtocol() + ":";
host = u.getHost();
port = u.getPort();
file = u.getFile();
ref = u.getRef();
// JDK 1.2 online doc infers that host could be null because it
// explicitly states that file cannot be null, but is silent on host.
//
// Note that this produces different results from JDK 1.2 as JDK 1.2
// ignores a non-default port if host is null or "". That is inconsistent
// with the spec since the result of this method is spec'ed so it can be
// used to construct a new URL that is equivalent to the original.
if (host == null)
host = "";
if (port >= 0 || ! (host.length() == 0))
resStr = resStr + "//" + host + (port < 0 ? "" : ":" + port);
resStr = resStr + file;
if (ref != null)
resStr = resStr + "#" + ref;
return resStr;
}
}