Package org.epics.archiverappliance.engine.model

Class ArchiveChannel

java.lang.Object
org.epics.archiverappliance.engine.model.ArchiveChannel
Direct Known Subclasses:
DeltaArchiveChannel, MonitoredArchiveChannel, ScannedArchiveChannel
public abstract class ArchiveChannel extends Object
Base for archived channels. An ArchiveChannel has
  1. A main PV; in the typical case, this would be the PV for the .VAL. The record processing timestamp from this PV constitutes identity.
  2. A optional collection of metadata/field PVs. Data from these PV's is stored as part of the mainPV.
  3. A SampleBuffer where the data from the main PV is stored.
  4. A Writer, typically the STS, where the data in the SampleBuffer is periodically flushed.
Version:
Initial version:CSS, 4-Jun-2012, Luofeng Li:added codes to support for the new archiver
Author:
Kay Kasemir

  • Field Details

    • SAVE_META_DATA_PERIOD_SECS

      public static final int SAVE_META_DATA_PERIOD_SECS
      See Also:

    • pvMetrics

      protected final PVMetrics pvMetrics
      pvMetrics for this channel. Ideally, we should move all metrics to this class.

    • latestDBRTimeEvent

      protected DBRTimeEvent latestDBRTimeEvent
      The latest DBRTimeEvent received from the control system

    • lastDBRTimeEvent

      protected DBRTimeEvent lastDBRTimeEvent
      The last DBRTimeEvent written to the archive.

  • Constructor Details

    • ArchiveChannel

      public ArchiveChannel(String name, Writer writer, int buffer_capacity, Instant last_archived_timestamp, ConfigService configservice, ArchDBRTypes archdbrtype, String controlPVname, int commandThreadID, boolean usePVAccess) throws Exception
      create archive channel
      Parameters:
      name - pv's name
      writer - the writer for this pv
      buffer_capacity - the sample buffer's capacity for this pv
      last_archived_timestamp - the last time stamp when this pv was archived
      configservice - the configservice of new archiver
      archdbrtype - the archiving dbr type
      controlPVname - the pv's name who control this pv to start archiving or stop archiving
      commandThreadID - - this is the index into the array of JCA command threads that processes this context.
      usePVAccess - - Should we use PVAccess to connect to this PV.
      Throws:
      Exception - error when creating archive channel for this pv

  • Method Details

    • getControlPVname

      public String getControlPVname()
      if this channel is started or stopped archiving by a another pv, return the pv's name
      Returns:
      the pv's name who control this channel archiving

    • setlastRotateLogsEpochSeconds

      public void setlastRotateLogsEpochSeconds(long lastRotateLogsEpochSecond)
      set the time stamp of the last value is stored in short term storage
      Parameters:
      lastRotateLogsEpochSecond - the time stamp of last value and it is the number of milliseconds since 1970/01/01

    • getWriter

      public Writer getWriter()
      get the writer for this channel
      Returns:
      the writer for this channel

    • getPVMetrics

      public PVMetrics getPVMetrics()
      get pv metrics for this channel
      Returns:
      PVMetrics

    • initializeMetaFieldPVS

      public void initializeMetaFieldPVS(String[] metaFields, ConfigService configservice, boolean usePVAccess, boolean useDBEProperties) throws IOException
      Throws:
      IOException

    • getPVData

      public ArrayListEventStream getPVData()
      get the combined ArrayListEventStream of prevouse and current
      Returns:
      ArrayListEventStream

    • getName

      public final String getName()
      Returns:
      Name of channel

    • getMechanism

      public abstract String getMechanism()
      Returns:
      Short description of sample mechanism

    • isConnected

      public final boolean isConnected()
      Returns:
      true if connected

    • start

      public final void start() throws Exception
      Start archiving this channel.
      Throws:
      Exception -  

    • stop

      public final void stop() throws Exception
      Stop archiving this channel
      Throws:
      Exception -  

    • getLastArchivedValue

      public final DBRTimeEvent getLastArchivedValue()
      Returns:
      Last value written to archive

    • getSampleBuffer

      public final SampleBuffer getSampleBuffer()
      Returns:
      Sample buffer

    • reset

      public void reset()
      Reset counters

    • handleNewValue

      protected boolean handleNewValue(DBRTimeEvent timeevent) throws Exception
      Called for each value received from PV.

      Base class remembers the most_recent_value, and asserts that one 'first' sample is archived. Derived class must call super().

      Parameters:
      timeevent - DBRTimeEvent
      Returns:
      true if the value was already written because it's the first value after startup or error, so there's no need to write that sample again.
      Throws:
      Exception -  

    • startUpMetaChannels

      public void startUpMetaChannels() throws Exception
      Start the metachannels

      Throws:
      Exception -  

    • shutdownMetaChannels

      public void shutdownMetaChannels()

    • handleDisconnected

      protected void handleDisconnected()
      Handle a disconnect event.

      Base class clears the most_recent_value and adds a 'disconnected' info sample. Subclasses may override, but must call super().

    • addValueToBuffer

      protected final void addValueToBuffer(DBRTimeEvent timeevent)
      Add given sample to buffer, performing a back-in-time check, updating the sample buffer error state.
      Parameters:
      timeevent - DBRTimeEvent

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • getCurrentCopyOfMetaFields

      public HashMap<String,String> getCurrentCopyOfMetaFields()
      Get the current value of all the meta fields.
      Returns:
      - Can return null if this PV has no meta fields.

    • getHostName

      public String getHostName()

    • getLowLevelChannelStateInfo

      public void getLowLevelChannelStateInfo(List<Map<String,String>> statuses)

    • isMetaPVConnected

      public boolean isMetaPVConnected(String metaFieldName)
      Get the archive channel for a particular metachannel.
      Parameters:
      metaFieldName -  
      Returns:
      boolean True or False

    • getMetaPVNames

      public Set<String> getMetaPVNames()
      Get the field names for which we have established channels.
      Returns:
      String the Meta PV names

    • getMetaChannelCount

      public int getMetaChannelCount()
      Number of field names for which we have established channels.
      Returns:
      int  

    • getConnectedMetaChannelCount

      public int getConnectedMetaChannelCount()
      Get the number of connected field channels
      Returns:
      int  

    • metaChannelsNeedStartingUp

      public boolean metaChannelsNeedStartingUp()
      Do any of the meta channels in this PV need starting up?
      Returns:
      boolean True or False

    • getSecondsElapsedSinceSearchRequest

      public long getSecondsElapsedSinceSearchRequest()
      Return the amount of time (in seconds) since we asked CAJ/JCA to connect to this channel.
      Returns:
      long  

    • getJCACommandThreadID

      public int getJCACommandThreadID()
      Returns:
      int the jCACommandThreadID

    • updateMetadataOnceADay

      public void updateMetadataOnceADay(EngineContext context)
      Use this method to do a caget on the metadata..
      Parameters:
      context - EngineContext

    • getLatestMetadata

      public HashMap<String,String> getLatestMetadata()
      Combine the metadata from various sources and return the latest copy.
      Returns:
      HashMap  

    • aboutToWriteBuffer

      public void aboutToWriteBuffer(DBRTimeEvent lastSample)

    • setPaused

      public void setPaused(boolean pausedVal)

    • isPaused

      public boolean isPaused()