org.clapper.curn.plugins
Class UserAgentPlugIn

java.lang.Object
  org.clapper.curn.plugins.UserAgentPlugIn

All Implemented Interfaces:

FeedConfigItemPlugIn, MainConfigItemPlugIn, PlugIn, PostConfigPlugIn, PreFeedDownloadPlugIn

public class UserAgentPlugIn
extends java.lang.Object
implements MainConfigItemPlugIn, FeedConfigItemPlugIn, PostConfigPlugIn, PreFeedDownloadPlugIn

The UserAgentPlugIn handles setting the global and per-feed HTTP user agent settings, overriding the default curn user agent setting. It intercepts the following configuration parameters:

Section	Parameter	Meaning
[curn]	UserAgent	The default user agent, if none is supplied in individual feed sections.
[Feedxxx]	UserAgent	User agent to use for a given feed.

Version:

$Revision: 6491 $

Constructor Summary

UserAgentPlugIn()
Default constructor (required).

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.
boolean	runFeedConfigItemPlugIn(java.lang.String sectionName, java.lang.String paramName, CurnConfig config, FeedInfo feedInfo) Called immediately after curn has read and processed a configuration item in a "feed" configuration section.
void	runMainConfigItemPlugIn(java.lang.String sectionName, java.lang.String paramName, CurnConfig config) Called immediately after curn has read and processed a configuration item in the main [curn] configuration section.
void	runPostConfigPlugIn(CurnConfig config) Called after the entire configuration has been read and parsed, but before any feeds are processed.
boolean	runPreFeedDownloadPlugIn(FeedInfo feedInfo, java.net.URLConnection urlConn) Called just before a feed is downloaded.

Methods inherited from class java.lang.Object

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

Constructor Detail

UserAgentPlugIn

public UserAgentPlugIn()

Default constructor (required).

Method Detail

getPlugInName

public java.lang.String getPlugInName()

Get a displayable name for the plug-in.

Specified by:

getPlugInName in interface PlugIn

Returns:

the name

getPlugInSortKey

public java.lang.String getPlugInSortKey()

Get the sort key for this plug-in.

Specified by:

getPlugInSortKey in interface PlugIn

Returns:

the sort key string.

initPlugIn

public void initPlugIn()
                throws CurnException

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

Specified by:

initPlugIn in interface PlugIn

Throws:

CurnException - on error

runMainConfigItemPlugIn

public void runMainConfigItemPlugIn(java.lang.String sectionName,
                                    java.lang.String paramName,
                                    CurnConfig config)
                             throws CurnException

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, this 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.

Specified by:

runMainConfigItemPlugIn in interface MainConfigItemPlugIn

Parameters:

sectionName - the name of the configuration section where the item was found

paramName - the name of the parameter

config - the CurnConfig object

Throws:

CurnException - on error

See Also:

CurnConfig

runFeedConfigItemPlugIn

public boolean runFeedConfigItemPlugIn(java.lang.String sectionName,
                                       java.lang.String paramName,
                                       CurnConfig config,
                                       FeedInfo feedInfo)
                                throws CurnException

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, this 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.

Specified by:

runFeedConfigItemPlugIn in interface FeedConfigItemPlugIn

Parameters:

sectionName - the name of the configuration section where the item was found

paramName - the name of the parameter

config - the active configuration

feedInfo - partially complete FeedInfo object for the feed. The URL is guaranteed to be present, but no other fields are.

Returns:

true to continue processing the feed, false to skip it

Throws:

CurnException - on error

See Also:

CurnConfig, FeedInfo, FeedInfo.getURL()

runPostConfigPlugIn

public void runPostConfigPlugIn(CurnConfig config)
                         throws CurnException

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.

Specified by:

runPostConfigPlugIn in interface PostConfigPlugIn

Parameters:

config - the parsed CurnConfig object

Throws:

CurnException - on error

See Also:

CurnConfig

runPreFeedDownloadPlugIn

public boolean runPreFeedDownloadPlugIn(FeedInfo feedInfo,
                                        java.net.URLConnection urlConn)
                                 throws CurnException

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

Specified by:

runPreFeedDownloadPlugIn in interface PreFeedDownloadPlugIn

Parameters:

feedInfo - the FeedInfo object for the feed to be downloaded

urlConn - the java.net.URLConnection object that will be used to download the feed's XML.

Returns:

true if curn should continue to process the feed, false to skip the feed

Throws:

CurnException - on error

See Also:

FeedInfo