PVLogger

java.lang.Object
- xal.service.pvlogger.PVLogger

```
public class PVLogger
extends java.lang.Object
```
Provides a public interface to the PV Logger package

Field Summary

Fields
Modifier and Type	Field and Description
`protected java.sql.Connection`	`_connection` current database connection
`protected ConnectionDictionary`	`_connectionDictionary` connection dictionary
`protected java.util.Map<java.lang.String,LoggerSession>`	`LOGGER_SESSIONS` logger sessions keyed by channel group ID
`protected xal.service.pvlogger.PersistentStore`	`PERSISTENT_STORE` database store
`protected xal.service.pvlogger.SnapshotPublisher`	`SNAPSHOT_PUBLISHER` snapshot publisher

Constructor Summary

Constructors
Constructor and Description

PVLogger()
Constructor

PVLogger(ConnectionDictionary connectionDictionary)
Primary Constructor

Constructors
Constructor and Description
`PVLogger()` Constructor
`PVLogger(ConnectionDictionary connectionDictionary)` Primary Constructor

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`closeConnection()` close the database connection if a connection exists and set the connection to null
`MachineSnapshot`	`fetchMachineSnapshot(long snapshotID)` Fetch the machine snapshot corresponding to the specified snasphot ID
`MachineSnapshot[]`	`fetchMachineSnapshotsInRange(java.lang.String type, java.util.Date startTime, java.util.Date endTime)` Fetch the machine snapshots within the specified time range.
`java.lang.String[]`	`fetchTypes()` Fetch channel groups as an array of types
`java.lang.String[]`	`fetchTypes(java.lang.String serviceID)` Fetch the channel groups associated with the service ID as an array of types
`protected void`	`finalize()` sql connections should be closed manually
`static PVLogger`	`getBrowsingInstance()` get an instance for browsing the PV Logger data
`ChannelGroup`	`getChannelGroup(java.lang.String type)` Get the channel group corresponding to the specified type.
`ConnectionDictionary`	`getConnectionDictionary()` get the connection dictionary
`protected java.sql.Connection`	`getDatabaseConnection()` get the current database connection creating it if necessary
`LoggerSession`	`getLoggerSession(java.lang.String groupID)` Get the logger session with the specified groupID
`java.util.Collection<LoggerSession>`	`getLoggerSessions()` Get all logger sessions managed by this PV Logger
`static PVLogger`	`getLoggingInstance()` get an instance for logging PV data to the database
`protected java.sql.Connection`	`getNewDatabaseConnection()` make a new database connection
`double`	`getPublishingPeriod()` Get the publishing period
`boolean`	`hasLoggerSession(java.lang.String groupID)` Determine if a logger session exists for the specified group
`boolean`	`isPublishing()` determine if the snapshot publisher is publishing snapshots periodically
`MachineSnapshot`	`loadChannelSnapshotsInto(MachineSnapshot machineSnapshot)` Fetch the channel snapshots from the data source and populate the machine snapshot
`static ConnectionDictionary`	`newBrowsingConnectionDictionary()` generate a new connection dictionary appropriate for browsing logged data
`static ConnectionDictionary`	`newLoggingConnectionDictionary()` generate a new connection dictionary appropriate for logging
`void`	`publishSnapshots()` publish any scheduled snapshots remaining in the queue
`LoggerSession`	`reloadLoggerSession(java.lang.String groupID)` Reload the logger session for the specified channel group
`void`	`removeAllLoggerSessions()` remove all logger sessions
`void`	`removeLoggerSession(java.lang.String groupID)` Stop the logger session with the specified group ID and remove it from the PV Logger
`java.util.List<LoggerSession>`	`requestEnabledLoggerSessionsForService(java.lang.String serviceID)` Request enabled logger sessions for the specified service
`LoggerSession`	`requestLoggerSession(java.lang.String groupID)` If a logger session already exists for the channel group, get it otherwise create a new one
`java.util.List<LoggerSession>`	`requestLoggerSessionsForService(java.lang.String serviceID)` Request logger sessions for the specified service
`void`	`restart()` restart logging sessions and publishing snapshots
`void`	`setConnectionDictionary(ConnectionDictionary dictionary)` set the connection dictionary
`void`	`setPublishingPeriod(double period)` Set the publishing period
`void`	`start()` start logging sessions and publishing snapshots
`void`	`stop()` stop logging sessions and publishing snapshots but publish any scheduled snapshots
`protected static boolean`	`testConnection(java.sql.Connection connection)` Test whether the connection is good

Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - PERSISTENT_STORE
```
protected final xal.service.pvlogger.PersistentStore PERSISTENT_STORE
```
    database store
  - SNAPSHOT_PUBLISHER
```
protected final xal.service.pvlogger.SnapshotPublisher SNAPSHOT_PUBLISHER
```
    snapshot publisher
  - _connectionDictionary
```
protected ConnectionDictionary _connectionDictionary
```
    connection dictionary
  - LOGGER_SESSIONS
```
protected java.util.Map<java.lang.String,LoggerSession> LOGGER_SESSIONS
```
    logger sessions keyed by channel group ID
  - _connection
```
protected java.sql.Connection _connection
```
    current database connection
- Constructor Detail
  - PVLogger
```
public PVLogger(ConnectionDictionary connectionDictionary)
```
    Primary Constructor
  - PVLogger
```
public PVLogger()
```
    Constructor
- Method Detail
  - getBrowsingInstance
```
public static PVLogger getBrowsingInstance()
```
    get an instance for browsing the PV Logger data
  - getLoggingInstance
```
public static PVLogger getLoggingInstance()
```
    get an instance for logging PV data to the database
  - newLoggingConnectionDictionary
```
public static ConnectionDictionary newLoggingConnectionDictionary()
```
    generate a new connection dictionary appropriate for logging
  - newBrowsingConnectionDictionary
```
public static ConnectionDictionary newBrowsingConnectionDictionary()
```
    generate a new connection dictionary appropriate for browsing logged data
  - getConnectionDictionary
```
public ConnectionDictionary getConnectionDictionary()
```
    get the connection dictionary
  - setConnectionDictionary
```
public void setConnectionDictionary(ConnectionDictionary dictionary)
```
    set the connection dictionary
  - getLoggerSession
```
public LoggerSession getLoggerSession(java.lang.String groupID)
```
    Get the logger session with the specified groupID
    
    Parameters:
    
    groupID - the channel group ID
    
    Returns:
    
    the logger session with the specified group ID or null if none exists
  - getLoggerSessions
```
public java.util.Collection<LoggerSession> getLoggerSessions()
```
    Get all logger sessions managed by this PV Logger
    
    Returns:
    
    the collection of logger sessions
  - removeAllLoggerSessions
```
public void removeAllLoggerSessions()
```
    remove all logger sessions
  - removeLoggerSession
```
public void removeLoggerSession(java.lang.String groupID)
```
    Stop the logger session with the specified group ID and remove it from the PV Logger
    
    Parameters:
    
    groupID - group ID of the logger session to remove
  - hasLoggerSession
```
public boolean hasLoggerSession(java.lang.String groupID)
```
    Determine if a logger session exists for the specified group
    
    Parameters:
    
    groupID - group ID of the logger session for which to look
    
    Returns:
    
    true if a session exists for the group and false if not
  - requestEnabledLoggerSessionsForService
```
public java.util.List<LoggerSession> requestEnabledLoggerSessionsForService(java.lang.String serviceID)
                                                                     throws java.sql.SQLException
```
    Request enabled logger sessions for the specified service
    
    Parameters:
    
    serviceID - service name
    
    Returns:
    
    the list of logger sessions
    
    Throws:
    
    java.sql.SQLException
  - requestLoggerSessionsForService
```
public java.util.List<LoggerSession> requestLoggerSessionsForService(java.lang.String serviceID)
                                                              throws java.sql.SQLException
```
    Request logger sessions for the specified service
    
    Parameters:
    
    serviceID - service name
    
    Returns:
    
    the list of logger sessions
    
    Throws:
    
    java.sql.SQLException
  - requestLoggerSession
```
public LoggerSession requestLoggerSession(java.lang.String groupID)
                                   throws java.sql.SQLException
```
    If a logger session already exists for the channel group, get it otherwise create a new one
    
    Parameters:
    
    groupID - the name of the channel group
    
    Returns:
    
    an existing logger session if one exists otherwise a new logger session or null if one could not be created
    
    Throws:
    
    java.sql.SQLException
  - reloadLoggerSession
```
public LoggerSession reloadLoggerSession(java.lang.String groupID)
                                  throws java.sql.SQLException
```
    Reload the logger session for the specified channel group
    
    Parameters:
    
    groupID - the name of the channel group
    
    Returns:
    
    the corresponding logger session or null if a corresponding logger session cannot be found or generated
    
    Throws:
    
    java.sql.SQLException
  - isPublishing
```
public boolean isPublishing()
```
    determine if the snapshot publisher is publishing snapshots periodically
  - start
```
public void start()
```
    start logging sessions and publishing snapshots
  - restart
```
public void restart()
```
    restart logging sessions and publishing snapshots
  - stop
```
public void stop()
```
    stop logging sessions and publishing snapshots but publish any scheduled snapshots
  - publishSnapshots
```
public void publishSnapshots()
```
    publish any scheduled snapshots remaining in the queue
  - getPublishingPeriod
```
public double getPublishingPeriod()
```
    Get the publishing period
    
    Returns:
    
    publishing period in seconds
  - setPublishingPeriod
```
public void setPublishingPeriod(double period)
```
    Set the publishing period
    
    Parameters:
    
    period - publishing period in seconds
  - fetchMachineSnapshot
```
public MachineSnapshot fetchMachineSnapshot(long snapshotID)
                                     throws java.sql.SQLException
```
    Fetch the machine snapshot corresponding to the specified snasphot ID
    
    Parameters:
    
    snapshotID - machine snaspshot ID
    
    Returns:
    
    machine snapshot corresponding to the specified ID
    
    Throws:
    
    java.sql.SQLException
  - fetchMachineSnapshotsInRange
```
public MachineSnapshot[] fetchMachineSnapshotsInRange(java.lang.String type,
                                                      java.util.Date startTime,
                                                      java.util.Date endTime)
                                               throws java.sql.SQLException
```
    Fetch the machine snapshots within the specified time range. If the type is not null, then restrict the machine snapshots to those of the specified type. The machine snapshots do not include the channel snapshots. A complete snapshot can be obtained using the fetchMachineSnapshot(id) method.
    
    Parameters:
    
    type - The type of machine snapshots to fetch or null for no restriction
    
    startTime - The start time of the time range
    
    endTime - The end time of the time range
    
    Returns:
    
    An array of machine snapshots meeting the specified criteria
    
    Throws:
    
    java.sql.SQLException
  - loadChannelSnapshotsInto
```
public MachineSnapshot loadChannelSnapshotsInto(MachineSnapshot machineSnapshot)
                                         throws java.sql.SQLException
```
    Fetch the channel snapshots from the data source and populate the machine snapshot
    
    Parameters:
    
    machineSnapshot - The machine snapshot for which to fetch the channel snapshots and load them
    
    Returns:
    
    the machineSnapshot which is the same as the parameter returned for convenience
    
    Throws:
    
    java.sql.SQLException
  - fetchTypes
```
public java.lang.String[] fetchTypes()
                              throws java.sql.SQLException
```
    Fetch channel groups as an array of types
    
    Returns:
    
    array of types corresponding to all of the channel groups
    
    Throws:
    
    java.sql.SQLException
  - fetchTypes
```
public java.lang.String[] fetchTypes(java.lang.String serviceID)
                              throws java.sql.SQLException
```
    Fetch the channel groups associated with the service ID as an array of types
    
    Parameters:
    
    serviceID - service ID of groups to fetch
    
    Returns:
    
    array of types corresponding to channel groups with the specified service ID
    
    Throws:
    
    java.sql.SQLException
  - getChannelGroup
```
public ChannelGroup getChannelGroup(java.lang.String type)
                             throws java.sql.SQLException
```
    Get the channel group corresponding to the specified type.
    
    Parameters:
    
    type - channel group type
    
    Throws:
    
    java.sql.SQLException
  - getDatabaseConnection
```
protected java.sql.Connection getDatabaseConnection()
```
    get the current database connection creating it if necessary
  - getNewDatabaseConnection
```
protected java.sql.Connection getNewDatabaseConnection()
```
    make a new database connection
  - closeConnection
```
public void closeConnection()
```
    close the database connection if a connection exists and set the connection to null
  - testConnection
```
protected static boolean testConnection(java.sql.Connection connection)
```
    Test whether the connection is good
    
    Parameters:
    
    connection - the connection to test
    
    Returns:
    
    true if the connection is good and false if not
  - finalize
```
protected void finalize()
                 throws java.lang.Throwable
```
    sql connections should be closed manually
    
    Overrides:
    
    finalize in class java.lang.Object
    
    Throws:
    
    java.lang.Throwable

Class PVLogger

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

PERSISTENT_STORE

SNAPSHOT_PUBLISHER

_connectionDictionary

LOGGER_SESSIONS

_connection

Constructor Detail

PVLogger

PVLogger

Method Detail

getBrowsingInstance

getLoggingInstance

newLoggingConnectionDictionary

newBrowsingConnectionDictionary

getConnectionDictionary

setConnectionDictionary

getLoggerSession

getLoggerSessions

removeAllLoggerSessions

removeLoggerSession

hasLoggerSession

requestEnabledLoggerSessionsForService

requestLoggerSessionsForService

requestLoggerSession

reloadLoggerSession

isPublishing

start

restart

stop

publishSnapshots

getPublishingPeriod

setPublishingPeriod

fetchMachineSnapshot

fetchMachineSnapshotsInRange

loadChannelSnapshotsInto

fetchTypes

fetchTypes

getChannelGroup

getDatabaseConnection

getNewDatabaseConnection

closeConnection

testConnection

finalize