public abstract class URLStreamHandler extends Object
URLStreamHandler
is the common superclass for all stream protocol handlers. A stream protocol handler knows how to make a connection for a particular protocol type, such as http
or https
. In most cases, an instance of a URLStreamHandler
subclass is not created directly by an application. Rather, the first time a protocol name is encountered when constructing a URL
, the appropriate stream protocol handler is automatically loaded.
Constructor | Description |
---|---|
URLStreamHandler() |
Constructor for subclasses to call. |
Modifier and Type | Method | Description |
---|---|---|
protected boolean |
equals |
Provides the default equals calculation. |
protected int |
getDefaultPort() |
Returns the default port for a URL parsed by this handler. |
protected InetAddress |
getHostAddress |
Get the IP address of our host. |
protected int |
hashCode |
Provides the default hash calculation. |
protected boolean |
hostsEqual |
Compares the host components of two URLs. |
protected abstract URLConnection |
openConnection |
Opens a connection to the object referenced by the URL argument. |
protected URLConnection |
openConnection |
Same as openConnection(URL), except that the connection will be made through the specified proxy; Protocol handlers that do not support proxying will ignore the proxy parameter and make a normal connection. |
protected void |
parseURL |
Parses the string representation of a URL into a URL object. |
protected boolean |
sameFile |
Compare two urls to see whether they refer to the same file, i.e., having the same protocol, host, port, and path. |
protected void |
setURL |
Deprecated. Use setURL(URL, String, String, int, String, String, String, String); |
protected void |
setURL |
Sets the fields of the URL argument to the indicated values. |
protected String |
toExternalForm |
Converts a URL of a specific protocol to a String . |
public URLStreamHandler()
protected abstract URLConnection openConnection(URL u) throws IOException
URL
argument. This method should be overridden by a subclass. If for the handler's protocol (such as HTTP or JAR), there exists a public, specialized URLConnection subclass belonging to one of the following packages or one of their subpackages: java.lang, java.io, java.util, java.net, the connection returned will be of that subclass. For example, for HTTP an HttpURLConnection will be returned, and for JAR a JarURLConnection will be returned.
u
- the URL that this connects to.URLConnection
object for the URL
.IOException
- if an I/O error occurs while opening the connection.protected URLConnection openConnection(URL u, Proxy p) throws IOException
Calling this method preempts the system's default ProxySelector
settings.
URL
and Proxy
are not null, then throws
UnsupportedOperationException
. Subclasses should override this method with an appropriate implementation.u
- the URL that this connects to.p
- the proxy through which the connection will be made. If direct connection is desired, Proxy.NO_PROXY should be specified.URLConnection
object for the URL
.IOException
- if an I/O error occurs while opening the connection.IllegalArgumentException
- if either u or p is null, or p has the wrong type.UnsupportedOperationException
- if the subclass that implements the protocol doesn't support this method.protected void parseURL(URL u, String spec, int start, int limit)
URL
into a URL
object. If there is any inherited context, then it has already been copied into the URL
argument.
The parseURL
method of URLStreamHandler
parses the string representation as if it were an http
specification. Most URL protocol families have a similar parsing. A stream protocol handler for a protocol that has a different syntax must override this routine.
u
- the URL
to receive the result of parsing the spec.spec
- the String
representing the URL that must be parsed.start
- the character index at which to begin parsing. This is just past the ':
' (if there is one) that specifies the determination of the protocol name.limit
- the character position to stop parsing at. This is the end of the string or the position of the "#
" character, if present. All information after the sharp sign indicates an anchor.IllegalArgumentException
- if the implementation of the protocol handler rejects any of the given parametersNullPointerException
- if u
is null
, or if start < limit
and spec
is null
protected int getDefaultPort()
URL
parsed by this handler.protected boolean equals(URL u1, URL u2)
u1
- a URL objectu2
- a URL objecttrue
if the two urls are considered equal, i.e. they refer to the same fragment in the same file.protected int hashCode(URL u)
u
- a URL objectint
suitable for hash table indexingprotected boolean sameFile(URL u1, URL u2)
u1
- a URL objectu2
- a URL objectprotected InetAddress getHostAddress(URL u)
u
- a URL objectInetAddress
representing the host IP address.protected boolean hostsEqual(URL u1, URL u2)
u1
- the URL of the first host to compareu2
- the URL of the second host to comparetrue
if and only if they are equal, false
otherwise.protected String toExternalForm(URL u)
URL
of a specific protocol to a String
.u
- the URL.URL
argument.protected void setURL(URL u, String protocol, String host, int port, String authority, String userInfo, String path, String query, String ref)
URL
argument to the indicated values. Only classes derived from URLStreamHandler are able to use this method to set the values of the URL fields.u
- the URL to modify.protocol
- the protocol name.host
- the remote host value for the URL.port
- the port on the remote machine.authority
- the authority part for the URL.userInfo
- the userInfo part of the URL.path
- the path component of the URL.query
- the query part for the URL.ref
- the reference.SecurityException
- if the protocol handler of the URL is different from this oneIllegalArgumentException
- if the implementation of the protocol handler rejects any of the given parametersNullPointerException
- if u
is null
@Deprecated protected void setURL(URL u, String protocol, String host, int port, String file, String ref)
URL
argument to the indicated values. Only classes derived from URLStreamHandler are able to use this method to set the values of the URL fields.u
- the URL to modify.protocol
- the protocol name. This value is ignored since 1.2.host
- the remote host value for the URL.port
- the port on the remote machine.file
- the file.ref
- the reference.SecurityException
- if the protocol handler of the URL is different from this oneIllegalArgumentException
- if the implementation of the protocol handler rejects any of the given parametersNullPointerException
- if u
is null
© 1993, 2023, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.
https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/net/URLStreamHandler.html