com.artima.place
Class WebServerLink

java.lang.Object
  |
  +--com.artima.place.WebServerLink

All Implemented Interfaces:

Link, ProgressEventGenerator, java.io.Serializable

public final class WebServerLink

extends java.lang.Object

implements Link, ProgressEventGenerator

Represents an HTTP-based link to a service on a webserver. The service will be retrieved from an HTTP URL. The MIME type of the HTTP GET must be application/x-serviceitem or application/serviceitem, which is a serialized marshalled Jini ServiceItem.

See Also:

Serialized Form

Constructor Summary

WebServerLink(URLString url)
Construct a WebServerLink with a URLString.

WebServerLink(URLString[] urls)
Construct a WebServerLink with an array of URLStrings.

Method Summary

void	addProgressListener(ProgressListener listener) Adds the specified ProgressListener to receive progress events from this object.
void	removeProgressListener(ProgressListener listener) Removes the specified ProgressListener so that it no longer receives progress events from this object.
net.jini.core.lookup.ServiceItem	retrieveService() Retrieves a service from a web server.
void	stopRetrieval() Request any ongoing retrieval to stop.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

WebServerLink

public WebServerLink(URLString url)

Construct a WebServerLink with a URLString.

Parameters:

url - the URL pointing to the serialized marshalled ServiceItem to be produced when this link's retrieveService method is invoked.

Throws:

NullPointerException - if passed url reference is null

java.lang.IllegalArgumentException - if the passed url is not an http URL

WebServerLink

public WebServerLink(URLString[] urls)

Construct a WebServerLink with an array of URLStrings.

Parameters:

urls - the URLs, in order, all pointing to separate copies of the serialized marshalled ServiceItem to be produced when this link's retrieveService method is invoked.

Throws:

NullPointerException - if passed urls array is null

java.lang.IllegalArgumentException - if passed urls array is empty

java.lang.IllegalArgumentException - if any of the passed urls are not http URLs

Method Detail

retrieveService

public net.jini.core.lookup.ServiceItem retrieveService()
                                                 throws java.rmi.RemoteException,
                                                        StoppedException

Retrieves a service from a web server. The MIME type of the data returned by the web server must be either application/x-serviceitem or application/serviceitem, which indicates the data is a serialized marshalled Jini ServiceItem. Any other MIME type will generate a RemoteException.

Specified by:

retrieveService in interface Link

Returns:

the ServiceItem the retrieved service item

Throws:

java.rmi.RemoteException - to indicate a failure in retrieving the service

StoppedException - to indicate that the request was stopped

stopRetrieval

public void stopRetrieval()

Request any ongoing retrieval to stop.

Specified by:

stopRetrieval in interface Link

addProgressListener

public void addProgressListener(ProgressListener listener)

Adds the specified ProgressListener to receive progress events from this object. If listener is null, no exception is thrown and no action is performed.

Specified by:

addProgressListener in interface ProgressEventGenerator

Parameters:

listener - the ProgressListener to add

removeProgressListener

public void removeProgressListener(ProgressListener listener)

Removes the specified ProgressListener so that it no longer receives progress events from this object. This method performs no function, nor does it throw an exception, if the listener specified by the argument was not previously added to this object. If listener is null, no exception is thrown and no action is performed.

Specified by:

removeProgressListener in interface ProgressEventGenerator

Parameters:

listener - the ProgressListener to remove