Class JunkBusterHandler

java.lang.Object

sunlabs.brazil.proxy.JunkBusterHandler

All Implemented Interfaces:

Handler

public class JunkBusterHandler
extends Object
implements Handler

Remove junk images from web pages. This approach is to take all requests for images that look like ads and instead return a dummy bitmap.

Other approaches to removing ads are to filter the HTML returned and (1) remove the ads altogether or (2) change the href in the ads to point to a different bitmap. The advantage of option (2) is that all ads can be changed to point to the same bitmap, increasing the caching performance of the browser.

Properties:

image

The file to contain the replacement image.

host

The regular expression matching url's to reject. If the expression starts with a '@', it interpreted as a file name (minus the @) that contains a new-line separated list of regular exporessions. See Regexp for more information on regular expressions.

Constructor Summary

Constructors

Constructor	Description
JunkBusterHandler()

Method Summary

Modifier and Type	Method	Description
boolean	init(Server server, String prefix)	Initializes the handler.
Regexp	loadUrls(Properties props, String prefix, String file)
boolean	respond(Request request)	Responds to an HTTP request.
boolean	sendReplacementImage(Request request)

Methods inherited from class Object

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

Constructor Details

JunkBusterHandler

public JunkBusterHandler()

Method Details

init

public boolean init(Server server,
 String prefix)

Description copied from interface: Handler

Initializes the handler.

Specified by:

init in interface Handler

Parameters:

server - The HTTP server that created this Handler. Typical Handlers will use Server.props to obtain run-time configuration information.

prefix - The handlers name. The string this Handler may prepend to all of the keys that it uses to extract configuration information from Server.props. This is set (by the Server and ChainHandler) to help avoid configuration parameter namespace collisions.

Returns:

true if this Handler initialized successfully, false otherwise. If false is returned, this Handler should not be used.

respond

public boolean respond(Request request)
                throws IOException

Description copied from interface: Handler

Responds to an HTTP request.

Specified by:

respond in interface Handler

Parameters:

request - The Request object that represents the HTTP request.

Returns:

true if the request was handled. A request was handled if a response was supplied to the client, typically by calling Request.sendResponse() or Request.sendError.

Throws:

IOException - if there was an I/O error while sending the response to the client. Typically, in that case, the Server will (try to) send an error message to the client and then close the client's connection.

The IOException should not be used to silently ignore problems such as being unable to access some server-side resource (for example getting a FileNotFoundException due to not being able to open a file). In that case, the Handler's duty is to turn that IOException into a HTTP response indicating, in this case, that a file could not be found.

loadUrls

public Regexp loadUrls(Properties props,
 String prefix,
 String file)

sendReplacementImage

public boolean sendReplacementImage(Request request)
                             throws IOException

Throws:

IOException