de.nava.informa.utils.poller
Class PollerWorkerThread

java.lang.Object
  java.lang.Thread
      de.nava.informa.utils.toolkit.WorkerThread
          de.nava.informa.utils.poller.PollerWorkerThread

All Implemented Interfaces:

Runnable

public class PollerWorkerThread
extends WorkerThread

Worker thread is the main processing unit. Worker thread is not dedicated to single channel, group or whatever else. It represents a single thread, which is capable of doing well-defined and unified job. WorkersManager submits jobs for free WorkerThread's. Workers simply do their jobs. This architecture allows to scale to as much threads as necessary.

Author:

Aleksey Gureev (spyromus@noizeramp.com)

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

Thread.State, Thread.UncaughtExceptionHandler

Field Summary

static int	POLICY_SCAN_ALL Scanning for new items performed fully.
static int	POLICY_SKIP_AFTER_EXISTING Scanning for new items in channel finishes when existing item detected.

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

PollerWorkerThread(PollerObserverIF observer, PollerApproverIF approver, int itemScanningPolicy, InputSourceProviderIF inputSourceProvider, InputStreamProviderIF inputStreamProvider)
Creates worker thread for poller with given observer and approver.

Method Summary

(package private) static boolean	channelHasChanged(ChannelIF o, ChannelIF n) Checks if channel has changed.
(package private) void	checkItems(ChannelIF newChannel, ChannelRecord record) Walks through the items and checks if new items present.
(package private) static boolean	differ(Object a, Object b) Checks if two objects differ.
protected void	processRecord(ChannelRecord record) Processes record.
void	setUserAgent(String userAgent) Sets specific user-agent to use when using HTTP protocol.

Methods inherited from class de.nava.informa.utils.toolkit.WorkerThread

getChannelInProcess, run, setQueue, terminate

Methods inherited from class java.lang.Thread

activeCount, checkAccess, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Field Detail

POLICY_SKIP_AFTER_EXISTING

public static final int POLICY_SKIP_AFTER_EXISTING

Scanning for new items in channel finishes when existing item detected.

See Also:

Constant Field Values

POLICY_SCAN_ALL

public static final int POLICY_SCAN_ALL

Scanning for new items performed fully.

See Also:

Constant Field Values

Constructor Detail

PollerWorkerThread

public PollerWorkerThread(PollerObserverIF observer,
                          PollerApproverIF approver,
                          int itemScanningPolicy,
                          InputSourceProviderIF inputSourceProvider,
                          InputStreamProviderIF inputStreamProvider)

Creates worker thread for poller with given observer and approver.

Parameters:

observer - observer object.

approver - approver object.

itemScanningPolicy - policy for item scanning.

inputSourceProvider - provider of InputSource for feeds' streams.

inputStreamProvider - provider of InputStream for feeds.

Method Detail

setUserAgent

public void setUserAgent(String userAgent)

Sets specific user-agent to use when using HTTP protocol.

Parameters:

userAgent - user agent or NULL to use default.

processRecord

protected final void processRecord(ChannelRecord record)

Processes record.

Specified by:

processRecord in class WorkerThread

Parameters:

record - record to process.

checkItems

final void checkItems(ChannelIF newChannel,
                      ChannelRecord record)

Walks through the items and checks if new items present.

Parameters:

newChannel - new channel taken from web.

record - record about currently existing channel to match against.

channelHasChanged

static boolean channelHasChanged(ChannelIF o,
                                 ChannelIF n)

Checks if channel has changed.

Parameters:

o - old channel.

n - new channel.

Returns:

result of the check.

differ

static boolean differ(Object a,
                      Object b)

Checks if two objects differ. NULL isn't different from other NULL.

Parameters:

a - object.

b - object.

Returns:

result of the check.