org.bitcoinj.core

Interface PeerFilterProvider

All Known Implementing Classes:

Wallet

public interface PeerFilterProvider

An interface which provides the information required to properly filter data downloaded from Peers. Note that an implementer is responsible for calling PeerGroup.recalculateFastCatchupAndFilter(org.bitcoinj.core.PeerGroup.FilterRecalculateMode) whenever a change occurs which effects the data provided via this interface.

Method Summary

Modifier and Type	Method and Description
void	beginBloomFilterCalculation() Called on all registered filter providers before getBloomFilterElementCount and getBloomFilter are called.
void	endBloomFilterCalculation()
BloomFilter	getBloomFilter(int size, double falsePositiveRate, long nTweak) Gets a bloom filter that contains all the necessary elements for the listener to receive relevant transactions.
int	getBloomFilterElementCount() Gets the number of elements that will be added to a bloom filter returned by getBloomFilter(int, double, long)
long	getEarliestKeyCreationTime() Returns the earliest timestamp (seconds since epoch) for which full/bloom-filtered blocks must be downloaded.
boolean	isRequiringUpdateAllBloomFilter() Whether this filter provider depends on the server updating the filter on all matches

Method Detail

getEarliestKeyCreationTime

long getEarliestKeyCreationTime()

Returns the earliest timestamp (seconds since epoch) for which full/bloom-filtered blocks must be downloaded. Blocks with timestamps before this time will only have headers downloaded. 0 requires that all blocks be downloaded, and thus this should default to System.currentTimeMillis()/1000.

beginBloomFilterCalculation

void beginBloomFilterCalculation()

Called on all registered filter providers before getBloomFilterElementCount and getBloomFilter are called. Once called, the provider should ensure that the items it will want to insert into the filter don't change. The reason is that all providers will have their element counts queried, and then a filter big enough for all of them will be specified. So the provider must use consistent state. There is guaranteed to be a matching call to endBloomFilterCalculation that can be used to e.g. unlock a lock.

getBloomFilterElementCount

int getBloomFilterElementCount()

Gets the number of elements that will be added to a bloom filter returned by getBloomFilter(int, double, long)

getBloomFilter

BloomFilter getBloomFilter(int size,
                           double falsePositiveRate,
                           long nTweak)

Gets a bloom filter that contains all the necessary elements for the listener to receive relevant transactions. Default value should be an empty bloom filter with the given size, falsePositiveRate, and nTweak.

isRequiringUpdateAllBloomFilter

boolean isRequiringUpdateAllBloomFilter()

Whether this filter provider depends on the server updating the filter on all matches

endBloomFilterCalculation

void endBloomFilterCalculation()