software.amazon.kinesis.coordinator.migration

Class AbstractMigrationClientVersionState

java.lang.Object

software.amazon.kinesis.coordinator.migration.AbstractMigrationClientVersionState

All Implemented Interfaces:

MigrationClientVersionState

Direct Known Subclasses:

MigrationClientVersion2xState, MigrationClientVersion3xState, MigrationClientVersion3xWithRollbackState, MigrationClientVersionUpgradeFrom2xState

public abstract class AbstractMigrationClientVersionState
extends Object
implements MigrationClientVersionState

Abstract base class for MigrationClientVersionState

This class implements the template method pattern for enter(ClientVersion):

1. If the DDB state's clientVersion does not match this state's MigrationClientVersionState.clientVersion(), creates or updates the DDB entry to reflect this state's version
2. Delegates to doEnter(ClientVersion) for state-specific initialization

Exception handling: All exceptions thrown during DDB operations (ProvisionedThroughputException, InvalidStateException, DependencyException) are wrapped into DependencyException and thrown back to the caller. The caller (either MigrationStateMachineImpl.initialize() which lets Scheduler retry, or MigrationStateMachineImpl.enter() which retries indefinitely) handles the retry logic.

MigrationClientVersionInitState does NOT extend this class since it does not write to DDB.

Field Summary

Fields

Modifier and Type	Field and Description
protected CoordinatorStateDAO	coordinatorStateDAO
protected MigrationState	curentMigrationState
protected boolean	entered
protected boolean	left

Constructor Summary

Constructors

Constructor and Description
AbstractMigrationClientVersionState()

Method Summary

Modifier and Type	Method and Description
protected abstract void	doEnter(ClientVersion fromClientVersion) State-specific enter logic.
void	enter(ClientVersion fromClientVersion) Template method that ensures DDB state matches this state's client version before delegating to the state-specific doEnter(ClientVersion) logic.

Methods inherited from class java.lang.Object

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

Methods inherited from interface software.amazon.kinesis.coordinator.migration.MigrationClientVersionState

clientVersion, leave

Field Detail

curentMigrationState

protected final MigrationState curentMigrationState

coordinatorStateDAO

protected final CoordinatorStateDAO coordinatorStateDAO

entered

protected boolean entered

left

protected boolean left

Constructor Detail

AbstractMigrationClientVersionState

public AbstractMigrationClientVersionState()

Method Detail

enter

public final void enter(ClientVersion fromClientVersion)
                 throws DependencyException

Template method that ensures DDB state matches this state's client version before delegating to the state-specific doEnter(ClientVersion) logic.

This method is idempotent — it only executes once per state instance.

Specified by:

enter in interface MigrationClientVersionState

Parameters:

fromClientVersion - the client version of the previous state

Throws:

DependencyException - if DDB operations fail

doEnter

protected abstract void doEnter(ClientVersion fromClientVersion)
                         throws DependencyException

State-specific enter logic. Called after DDB state has been verified/updated.

Parameters:

fromClientVersion - the client version of the previous state

Throws:

DependencyException - if state-specific initialization fails