sunlabs.brazil.filter
Class ReplaceFilter

java.lang.Object
  sunlabs.brazil.filter.ReplaceFilter (view source)

All Implemented Interfaces:

Filter, Handler

public class ReplaceFilter
extends Object
implements Filter

Filter to replace current content with a static form, or template. This should be called the TemplateFilter, but that name's already taken. The content is replaced by the template lock-stock-and-barrel. Typically, an upstream filter has extracted the relevent parts of the content, and a down-stream filter will combine it with the template. The filename to use for the template is computed at each request, so it may be modified dynamically. The following server properties are used:

type

Text subtype of content to filter. Defaults to "html"

debug

If set, the template is re-read each time. Otherwise a cached copy is used.

fileName

Name of the file to use as the form or template. The file is searched for as a Resource if not found in the filesystem.

root

The document root used to find the template file. If not found, "root" with no prefix is used instead.

capture

If set, the name of the property to "capture" the content that is about to be replaced. (This is equivalent to the "all" property of the contentTemplate.

Constructor Summary

ReplaceFilter()

Method Summary

byte[]	filter(Request request, MimeHeaders headers, byte[] content) Grab the template file name, Read in the file, and deliver it as content.
boolean	init(Server server, String prefix) Initializes the handler.
boolean	respond(Request request) This is the request object before the content was fetched
boolean	shouldFilter(Request request, MimeHeaders headers) Only replace text documents

Methods inherited from class java.lang.Object

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

Constructor Detail

ReplaceFilter

public ReplaceFilter()

Method Detail

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)

This is the request object before the content was fetched

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.

shouldFilter

public boolean shouldFilter(Request request,
                            MimeHeaders headers)

Only replace text documents

Specified by:

shouldFilter in interface Filter

Parameters:

request - The in-progress HTTP request.

headers - The MIME headers generated by the wrapped Handler.

Returns:

true if this filter would like to examine and possibly rewrite the content, false otherwise.

filter

public byte[] filter(Request request,
                     MimeHeaders headers,
                     byte[] content)

Grab the template file name, Read in the file, and deliver it as content.

Specified by:

filter in interface Filter

Parameters:

request - The finished HTTP request.

headers - The MIME headers generated by the Handler.

content - The output from the Handler that this Filter may rewrite.

Returns:

The rewritten content. The Filter may return the original content unchanged. The Filter may return null to indicate that the FilterHandler should stop processing the request and should not return any content to the client.