Package com.inductiveautomation.historian.gateway.api.storage.realtime

Class DataCollectorFactory

java.lang.Object

com.inductiveautomation.historian.gateway.api.storage.realtime.DataCollectorFactory

public class DataCollectorFactory
extends Object

Factory for creating and managing DataCollector instances.

This singleton factory provides methods for creating, retrieving, and managing data collectors associated with storage engines. It supports different collection strategies based on the specified CollectionMode:

• MANUAL - Collects only the latest values when explicitly requested
• STREAMING - Automatically collects all values at regular intervals

The factory maintains a registry of active collectors and provides thread pools for executing collection operations and scheduling periodic tasks. It ensures that only one collector exists per storage engine and collector ID combination.

This class uses a thread-safe implementation to handle concurrent access and provides proper resource management through shutdown operations.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	DataCollectorFactory.AbstractDataCollector	Base abstract class for data collector implementations that provides common functionality for both manual and streaming collection modes.
protected static class	DataCollectorFactory.DefaultSnapshotProcessor	Default implementation of the SnapshotProcessor interface that forwards collected data directly to the storage engine.
protected class	DataCollectorFactory.ManualDataCollector	Data collector implementation for the CollectionMode.MANUAL mode.
protected class	DataCollectorFactory.StreamingDataCollector	Base abstract class for data collector implementations that provides common functionality for both manual and streaming collection modes.

Method Summary

Modifier and Type	Method	Description
static DataCollectorFactory	getInstance()	Gets the singleton instance of the factory.
DataCollector	getOrCreateCollector(StorageEngine storageEngine, CollectorId collectorId)	Creates or retrieves a data collector with the default snapshot processor.
DataCollector	getOrCreateCollector(StorageEngine storageEngine, CollectorId collectorId, SnapshotProcessor dataProcessor)	Creates or retrieves a data collector with a custom snapshot processor.
void	removeCollectors(StorageEngine storageEngine)	Removes all collectors associated with the specified storage engine.

Methods inherited from class java.lang.Object

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

Method Details

getInstance

public static DataCollectorFactory getInstance()

Gets the singleton instance of the factory.

If the instance doesn't exist yet, it is created in a thread-safe manner.

Returns:

The singleton instance of DataCollectorFactory

getOrCreateCollector

public DataCollector getOrCreateCollector(StorageEngine storageEngine,
 CollectorId collectorId)

Creates or retrieves a data collector with the default snapshot processor.

This method creates a storage session with the default strategy of forwarding collected data to the historian interface when appropriate.

Parameters:

storageEngine - The storage engine to associate with the collector

collectorId - The identifier for the collector, including its collection mode

Returns:

A DataCollector instance for the specified parameters

getOrCreateCollector

public DataCollector getOrCreateCollector(StorageEngine storageEngine,
 CollectorId collectorId,
 SnapshotProcessor dataProcessor)

Creates or retrieves a data collector with a custom snapshot processor.

This method creates a storage session with a custom storage strategy. The default session will collect data based on the mode, and when the data is ready to be sent, it will send it to the storage strategy.

This is a way for implementors to get the vast majority of the management between tags, tag groups, collection modes, and so on handled for them, while still having full control over how data is actually sent to the storage system internally.

Parameters:

storageEngine - The storage engine to associate with the collector

collectorId - The identifier for the collector, including its collection mode

dataProcessor - The custom snapshot processor to use for processing collected data

Returns:

A DataCollector instance for the specified parameters

removeCollectors

public void removeCollectors(StorageEngine storageEngine)

Removes all collectors associated with the specified storage engine.

This method safely shuts down all collectors before removing them from the registry. The shutdown process ensures that any pending data is processed before the collectors are terminated.

Parameters:

storageEngine - The storage engine whose collectors should be removed