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§4.11 Class URLStreamHandler

public  abstract  class  java.net.URLStreamHandler
    extends  java.lang.Object  (I-§1.12)
{
        // Constructors
    public URLStreamHandler();	§4.11.1

        // Methods
    protected abstract URLConnection openConnection(URL  u);	§4.11.2
    protected void parseURL(URL  u, String  spec,	§4.11.3
                                        int  start, int  limit);
    protected void setURL(URL  u, String  protocol,	§4.11.4
                String  host, int  port, String  file, String  ref);
    protected String toExternalForm(URL  u);	§4.11.5
}

The abstract class 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, ftp, or gopher,

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 appropropriate stream protocol handler is automatically loaded. See I-§4.8.2 for complete details.

URLStreamHandler

public URLStreamHandler()

The default constructor.

openConnection

protected abstract URLConnection openConnection(URL  u)

throws IOException

Opens a connection to the object referenced by the URL argument.

Parameters:: u -the URL that this connects to
Returns:: a URLConnection object for the URL.
Throws: IOException (I-§2.29); If an IO error occurs while opening the conection.

parseURL

protected void

parseURL(URL  u, String  spec, int  start, int  limit)

Parses the string representation of a URL into a URL object.

If there is any inherited context then it has already been copied into the URL argument

This method 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.

Parameters:: u -the URL to receive the result of parsing the spec; spec -the String representing the URL which 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 protocl 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.

setURL

protected void setURL(URL  u, String  protocol, String  host,

                                            int  port, String  file, String  ref)

Sets the fields of the URL argument to the indicated values.

Parameters:: u -the URL to modify; protocol -the protocol name; host -the remote host value for the URL; port -the port on the remote machine; file -the file; ref -the reference

toExternalForm

protected String toExternalForm(URL  u)

Converts a URL of a specific protocol to a String.

Parameters:: u -the URL
Returns:: a string representation of the URL argument.

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