org.clapper.curn
Interface PlugIn

All Known Subinterfaces:

CacheLoadedPlugIn, FeedConfigItemPlugIn, MainConfigItemPlugIn, OutputHandlerConfigItemPlugIn, PostConfigPlugIn, PostFeedDownloadPlugIn, PostFeedOutputPlugIn, PostFeedParsePlugIn, PostOutputHandlerFlushPlugIn, PostOutputPlugIn, PreCacheSavePlugIn, PreFeedDownloadPlugIn, PreFeedOutputPlugIn, ShutdownPlugIn, StartupPlugIn, UnknownSectionConfigItemPlugIn

All Known Implementing Classes:

AllowEmbeddedHTMLPlugIn, ArticleFilterPlugIn, CommonXMLFixupsPlugIn, DataPersisterFactory, DisableFeedPlugIn, DisableOutputHandlerPlugIn, EmailOutputPlugIn, EmptyArticleSummaryPlugIn, FeedMaxSummarySizePlugIn, GzipDownloadPlugIn, IgnoreDuplicateArticlesPlugIn, MetaPlugIn, ParsedFeedURLEditPlugIn, RawFeedEditPlugIn, RawFeedSaveAsPlugIn, ShowAuthorsPlugIn, ShowDatesPlugIn, SortArticlesPlugIn, TitleOverridePlugIn, Tool, UserAgentPlugIn, ZipOutputPlugIn

public interface PlugIn

This interface defines the methods that must be supported by a class that is to be plugged into curn as a generalized plug-in. curn plug-ins are invoked at various phases of curn execution.

Each plug-in phase is represented by its own Java interface, and each interface has exactly one method. A plug-in that intercepts multiple curn processing phases must implement the interfaces for each of the phases. Here are the plug-in phases, in execution order.

Plug-in interface	Plug-in method	Description
StartupPlugIn	runStartupPlugIn()	Called immediately after curn has started, but before it has loaded its configuration file or its cache. Intercepting this phase is useful if a plug-in needs to perform initialization.
MainConfigItemPlugIn	runMainConfigItemPlugIn()	Called immediately after curn has read and processed a configuration item in the main [curn] configuration section. All configuration items are passed, one by one, to each loaded plug-in. If a plug-in class is not interested in a particular configuration item, its runMainConfigItemPlugIn() method should simply return without doing anything. Note that some configuration items may simply be variable assignment; there's no real way to distinguish a variable assignment from a blessed configuration item.
FeedConfigItemPlugIn	runFeedConfigItemPlugIn()	Called immediately after curn has read and processed a configuration item in a "Feed" configuration section. All configuration items are passed, one by one, to each loaded plug-in. If a plug-in class is not interested in a particular configuration item, its runFeedConfigItemPlugIn() method should simply return without doing anything. Note that some configuration items may simply be variable assignment; there's no real way to distinguish a variable assignment from a blessed configuration item.
OutputHandlerConfigItemPlugIn	runOutputHandlerConfigItemPlugIn()	Called immediately after curn has read and processed a configuration item in an "OutputHandler" configuration section. All configuration items are passed, one by one, to each loaded plug-in. If a plug-in class is not interested in a particular configuration item, its runOutputHandlerConfigItemPlugIn() method should simply return without doing anything. Note that some configuration items may simply be variable assignment; there's no real way to distinguish a variable assignment from a blessed configuration item.
UnknownSectionConfigItemPlugIn	runUnknownSectionConfigItemPlugIn()	Called immediately after curn has read and processed a configuration item in an unknown configuration section. All configuration items are passed, one by one, to each loaded plug-in. If a plug-in class is not interested in a particular configuration item, its runUnknownSectionConfigItemPlugIn() method should simply return without doing anything. Note that some configuration items may simply be variable assignment; there's no real way to distinguish a variable assignment from a blessed configuration item.
PostConfigPlugIn	runPostConfigPlugIn()	Called after the entire configuration has been read and parsed, but before any feeds are processed. Intercepting this event is useful for plug-ins that want to adjust the configuration. For instance, the curn command-line wrapper intercepts this plug-in event so it can adjust the configuration to account for command line options.
CacheLoadedPlugIn	runCacheLoadedPlugIn()	Called after the curn cache has been read (and after any expired entries have been purged), but before any feeds are processed.
PreFeedDownloadPlugIn	runPreFeedDownloadPlugIn()	Called just before a feed is downloaded. This method can return false to signal curn that the feed should be skipped. The plug-in method can also set values on the URLConnection used to download the plug-in, via URL.setRequestProperty(). (Note that all URLs, even file: URLs, are passed into this method. Setting a request property on the URLConnection object for a file: URL will have no effect--though it isn't specifically harmful.) Possible uses for a pre-feed download plug-in include: filtering on feed URL to prevent downloading non-matching feeds changing the default User-Agent value setting a non-standard HTTP header field
PostFeedDownloadPlugIn	runPostFeedDownloadPlugIn()	Called immediately after a feed is downloaded. This method can return false to signal curn that the feed should be skipped. For instance, a plug-in that filters on the unparsed XML feed content could use this method to weed out non-matching feeds before they are downloaded.
PostFeedParsePlugIn	runPostFeedParsePlugIn()	Called immediately after a feed is parsed, but before it is otherwise processed. A post-feed parse plug-in has access to the parsed RSS feed data, via an RSSChannel object. This method can return false to signal curn that the feed should be skipped. For instance, a plug-in that filters on the parsed feed data could use this method to weed out non-matching feeds before they are downloaded. Similarly, a plug-in that edits the parsed data (removing or editing individual items, for instance) could use method to do so.
PreFeedOutputPlugIn	runPreFeedOutputPlugIn()	Called immediately before a parsed feed is passed to an output handler. A pre-feed output plug-in cannot affect the feed's processing. (The time to stop the processing of a feed is in one of the other, preceding phases.) This method will be called multiple times for each feed if there are multiple output handlers.
PostFeedOutputPlugIn	runPostFeedOutputPlugIn()	Called immediately after a parsed feed is passed to an output handler. A post-feed output plug-in cannot affect the feed's processing. (The time to stop the processing of a feed is in one of the other, preceding phases.) This method will be called multiple times for each feed if there are multiple output handlers.
PostOutputHandlerFlushPlugIn	runPostOutputHandlerFlushPlugIn()	Called immediately after an output handler is flushed (i.e., after it has been called to process all feeds and its output has been written to a temporary file), but before that output is displayed, emailed, etc.
PostOutputPlugIn	runPostOutputPlugIn()	Called after curn has flush all output handlers. A post-output plug-in is a useful place to consolidate the output from all output handlers. For instance, such a plug-in might pack all the output into a zip file, or email it.
PreCacheSavePlugIn	runPreCacheSavePlugIn()	Called right before the curn cache is to be saved. A plug-in might choose to edit the cache at this point.
ShutdownPlugIn	runShutdownPlugIn()	Called just before curn gets ready to exit. This method allows plug-ins to perform any clean-up they require.

Version:

$Revision: 6491 $

Method Summary

java.lang.String	getPlugInName() Get a displayable name for the plug-in.
java.lang.String	getPlugInSortKey() Get the sort key for this plug-in.
void	initPlugIn() Initialize the plug-in.

Method Detail

getPlugInName

java.lang.String getPlugInName()

Get a displayable name for the plug-in.

Returns:

the name

getPlugInSortKey

java.lang.String getPlugInSortKey()

Get the sort key for this plug-in.

Returns:

the sort key string.

initPlugIn

void initPlugIn()
                throws CurnException

Initialize the plug-in. This method is called before any of the plug-in methods are called.

Throws:

CurnException - on error