Package com.privatechain.core.event

Class BlockchainEvent

java.lang.Object

com.privatechain.core.event.BlockchainEvent

Direct Known Subclasses:

BlockchainEvent.BlockAddedEvent, BlockchainEvent.ForkDetectedEvent, BlockchainEvent.PeerConnectedEvent, BlockchainEvent.PeerDisconnectedEvent, BlockchainEvent.TransactionSubmittedEvent

public abstract sealed class BlockchainEvent
extends Object
permits BlockchainEvent.BlockAddedEvent, BlockchainEvent.TransactionSubmittedEvent, BlockchainEvent.PeerConnectedEvent, BlockchainEvent.PeerDisconnectedEvent, BlockchainEvent.ForkDetectedEvent

Sealed base type for all events published on the BlockchainEventBus.

The sealed hierarchy guarantees that every event variant is known at compile time, enabling exhaustive switch expressions in consumer code (FR-EVENT-01). New event types can only be added by the library maintainer, which is intentional: it prevents external subclasses from breaking switch exhaustiveness.

Event variants

• BlockchainEvent.BlockAddedEvent — a new block was appended to the chain
• BlockchainEvent.TransactionSubmittedEvent — a transaction entered the mempool
• BlockchainEvent.PeerConnectedEvent — a remote peer established a connection
• BlockchainEvent.PeerDisconnectedEvent — a remote peer disconnected
• BlockchainEvent.ForkDetectedEvent — two competing blocks at the same height were found

Handling events

 eventBus.register(event -> {
     if (event instanceof BlockchainEvent.BlockAddedEvent e) {
         log.info("Block #{} added", e.getBlock().getIndex());
     } else if (event instanceof BlockchainEvent.TransactionSubmittedEvent e) {
         metricsCounter.increment();
     }
 });
 

Since:

1.0.0

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	BlockchainEvent.BlockAddedEvent	Fired after a new block is successfully appended to the canonical chain.
static final class	BlockchainEvent.ForkDetectedEvent	Fired when the node detects two competing valid blocks at the same chain height.
static final class	BlockchainEvent.PeerConnectedEvent	Fired when a new peer successfully establishes a TCP connection to this node.
static final class	BlockchainEvent.PeerDisconnectedEvent	Fired when a peer connection is closed, either gracefully or due to an error.
static final class	BlockchainEvent.TransactionSubmittedEvent	Fired after a transaction successfully passes validation and enters the mempool.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	BlockchainEvent()	Protected constructor for subclasses; sets occurredAt to the current time.

Method Summary

Modifier and Type	Method	Description
Instant	getOccurredAt()	Returns the UTC instant at which this event occurred.

Methods inherited from class java.lang.Object

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

Constructor Details

BlockchainEvent

protected BlockchainEvent()

Protected constructor for subclasses; sets occurredAt to the current time.

Method Details

getOccurredAt

public Instant getOccurredAt()

Returns the UTC instant at which this event occurred.

Returns:

non-null event timestamp