Package org.bitcoinj.core.listeners

Class DownloadProgressTracker

java.lang.Object

org.bitcoinj.core.listeners.DownloadProgressTracker

All Implemented Interfaces:

BlockchainDownloadEventListener, BlocksDownloadedEventListener, ChainDownloadStartedEventListener

public class DownloadProgressTracker
extends Object
implements BlockchainDownloadEventListener

An implementation of BlockchainDownloadEventListener that listens to chain download events and tracks progress as a percentage. The default implementation prints progress to stdout, but you can subclass it and override the progress method to update a GUI instead.

Constructor Summary

Constructors

Constructor	Description
DownloadProgressTracker()

Method Summary

Modifier and Type	Method	Description
void	await()	Wait for the chain to be downloaded.
protected void	doneDownload()	Called when we are done downloading the block chain.
ListenableCompletableFuture<Long>	getFuture()	Returns a listenable future that completes with the height of the best chain (as reported by the peer) once chain download seems to be finished.
void	onBlocksDownloaded(Peer peer, Block block, FilteredBlock filteredBlock, int blocksLeft)	Called on a Peer thread when a block is received.
void	onChainDownloadStarted(Peer peer, int blocksLeft)	Called when a download is started with the initial number of blocks to be downloaded.
protected void	progress(double pct, int blocksSoFar, Instant time)	Called when download progress is made.
protected void	startDownload(int blocks)	Called when download is initiated.

Methods inherited from class java.lang.Object

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

Constructor Details

DownloadProgressTracker

public DownloadProgressTracker()

Method Details

onChainDownloadStarted

public void onChainDownloadStarted(Peer peer,
 int blocksLeft)

Description copied from interface: ChainDownloadStartedEventListener

Called when a download is started with the initial number of blocks to be downloaded.

Specified by:

onChainDownloadStarted in interface ChainDownloadStartedEventListener

Parameters:

peer - the peer receiving the block

blocksLeft - the number of blocks left to download

onBlocksDownloaded

public void onBlocksDownloaded(Peer peer,
 Block block,
 @Nullable
 FilteredBlock filteredBlock,
 int blocksLeft)

Description copied from interface: BlocksDownloadedEventListener

Called on a Peer thread when a block is received.

The block may be a Block object that contains transactions, a Block object that is only a header when fast catchup is being used. If set, filteredBlock can be used to retrieve the list of associated transactions.

Specified by:

onBlocksDownloaded in interface BlocksDownloadedEventListener

Parameters:

peer - the peer receiving the block

block - the downloaded block

filteredBlock - if non-null, the object that wraps the block header passed as the block param.

blocksLeft - the number of blocks left to download

progress

protected void progress(double pct,
 int blocksSoFar,
 Instant time)

Called when download progress is made.

Parameters:

pct - the percentage of chain downloaded, estimated

time - the time of the last block downloaded

startDownload

protected void startDownload(int blocks)

Called when download is initiated.

Parameters:

blocks - the number of blocks to download, estimated

doneDownload

protected void doneDownload()

Called when we are done downloading the block chain.

await

public void await()
           throws InterruptedException

Wait for the chain to be downloaded.

Throws:

InterruptedException

getFuture

public ListenableCompletableFuture<Long> getFuture()

Returns a listenable future that completes with the height of the best chain (as reported by the peer) once chain download seems to be finished.