| Known Indirect Subclasses |
Interface for user-specific implementation details of the connector.
Implementations must be thread-safe. Implementations are discouraged from keeping any state locally except perhaps soft-state such as a connection cache.
Public Method Summary
| abstract void |
destroy()
Shuts down and releases connector resources.
|
| String |
getDefaultId()
Gets the default connector ID.
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| abstract void |
init(T context)
Initializes the connector with the current context.
|
| abstract void |
saveCheckpoint(boolean isShutdown)
Saves checkpoint information such as current traversal position or incremental change tokens.
|
| abstract void |
traverse()
Implements a connector-specific traversal strategy.
|
Public Methods
public abstract void destroy ()
Shuts down and releases connector resources.
public String getDefaultId ()
Gets the default connector ID.
public abstract void init (T context)
Initializes the connector with the current context.
Initialization is the ideal time to start any threads to do extra behind-the-scenes work.
The context allows access to other useful objects that can be used at any time.
If an unrecoverable fatal error occurs during initialization, throw a StartupException to cancel the startup process. If a recoverable error occurs during
initialization, most Exception instances other than StartupException cause a
retry of initialization after a short delay.
Parameters
| context | ConnectorContext instance for accessing framework objects |
|---|
Throws
| Exception | if errors occur during connector initialization |
|---|
public abstract void saveCheckpoint (boolean isShutdown)
Saves checkpoint information such as current traversal position or incremental change tokens.
The checkpoint contents are implementation-specific as defined by the connector code. This method is called during shutdown to allow the connector to save the current traversal state.
Parameters
| isShutdown | flag indicating a connector shutdown |
|---|
Throws
| IOException | if saving checkpoint fails. |
|---|---|
| InterruptedException | if an IO operations throws it |
public abstract void traverse ()
Implements a connector-specific traversal strategy.
This method may take a while and implementations may want to call sleep(long)
occasionally to reduce load.
If fatal errors occur, throw an IOException or RuntimeException.
In the case of an error, the ExceptionHandler defined in ConnectorContext
determines if and when to retry.
Throws
| IOException | if getting data access errors |
|---|---|
| InterruptedException | if an IO operations throws it |