Package org.bitcoinj.core

Class FullPrunedBlockChain

java.lang.Object

org.bitcoinj.core.AbstractBlockChain

org.bitcoinj.core.FullPrunedBlockChain

public class FullPrunedBlockChain
extends AbstractBlockChain

A FullPrunedBlockChain works in conjunction with a FullPrunedBlockStore to verify all the rules of the Bitcoin system, with the downside being a large cost in system resources. Fully verifying means all unspent transaction outputs are stored. Once a transaction output is spent and that spend is buried deep enough, the data related to it is deleted to ensure disk space usage doesn't grow forever. For this reason a pruning node cannot serve the full block chain to other clients, but it nevertheless provides the same security guarantees as Bitcoin Core does.

Nested Class Summary

Nested classes/interfaces inherited from class org.bitcoinj.core.AbstractBlockChain

AbstractBlockChain.NewBlockType

Field Summary

Fields

Modifier and Type	Field	Description
protected FullPrunedBlockStore	blockStore	Keeps a map of block hashes to StoredBlocks.

Fields inherited from class org.bitcoinj.core.AbstractBlockChain

chainHead, FP_ESTIMATOR_ALPHA, FP_ESTIMATOR_BETA, lock, params

Constructor Summary

Constructors

Constructor	Description
FullPrunedBlockChain(NetworkParameters params, java.util.List<Wallet> listeners, FullPrunedBlockStore blockStore)	Constructs a block chain connected to the given list of wallets and a store.
FullPrunedBlockChain(NetworkParameters params, FullPrunedBlockStore blockStore)	Constructs a block chain connected to the given store.
FullPrunedBlockChain(NetworkParameters params, Wallet wallet, FullPrunedBlockStore blockStore)	Constructs a block chain connected to the given wallet and store.

Method Summary

Modifier and Type	Method	Description
protected StoredBlock	addToBlockStore(StoredBlock storedPrev, Block block)	Adds/updates the given Block with the block store.
protected StoredBlock	addToBlockStore(StoredBlock storedPrev, Block header, TransactionOutputChanges txOutChanges)	Adds/updates the given StoredBlock with the block store.
protected TransactionOutputChanges	connectTransactions(int height, Block block)	Connect each transaction in block.transactions, verifying them as we go and removing spent outputs If an error is encountered in a transaction, no changes should be made to the underlying BlockStore.
protected TransactionOutputChanges	connectTransactions(StoredBlock newBlock)	Used during reorgs to connect a block previously on a fork
protected void	disconnectTransactions(StoredBlock oldBlock)	This is broken for blocks that do not pass BIP30, so all BIP30-failing blocks which are allowed to fail BIP30 must be checkpointed.
protected void	doSetChainHead(StoredBlock chainHead)	Called before setting chain head in memory.
protected StoredBlock	getStoredBlockInCurrentScope(Sha256Hash hash)	For a standard BlockChain, this should return blockStore.get(hash), for a FullPrunedBlockChain blockStore.getOnceUndoableStoredBlock(hash)
protected void	notSettingChainHead()	Called if we (possibly) previously called disconnectTransaction/connectTransactions, but will not be calling preSetChainHead as a block failed verification.
protected void	rollbackBlockStore(int height)	Rollback the block store to a given height.
void	setRunScripts(boolean value)	Whether or not to run scripts whilst accepting blocks (i.e.
protected boolean	shouldVerifyTransactions()	Whether or not we are maintaining a set of unspent outputs and are verifying all transactions.

Methods inherited from class org.bitcoinj.core.AbstractBlockChain

add, add, addNewBestBlockListener, addNewBestBlockListener, addReorganizeListener, addReorganizeListener, addTransactionReceivedListener, addTransactionReceivedListener, addWallet, drainOrphanBlocks, estimateBlockTime, estimateBlockTimeInstant, getBestChainHeight, getBlockStore, getChainHead, getFalsePositiveRate, getHeightFuture, getOrphanRoot, getVersionTally, isOrphan, removeNewBestBlockListener, removeReorganizeListener, removeTransactionReceivedListener, removeWallet, resetFalsePositiveEstimate, setChainHead, trackFilteredTransactions

Methods inherited from class java.lang.Object

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

Field Detail

blockStore

protected final FullPrunedBlockStore blockStore

Keeps a map of block hashes to StoredBlocks.

Constructor Detail

FullPrunedBlockChain

public FullPrunedBlockChain(NetworkParameters params,
                            Wallet wallet,
                            FullPrunedBlockStore blockStore)
                     throws BlockStoreException

Constructs a block chain connected to the given wallet and store. To obtain a Wallet you can construct one from scratch, or you can deserialize a saved wallet from disk using Wallet.loadFromFile(File, WalletExtension...)

Throws:

BlockStoreException

FullPrunedBlockChain

public FullPrunedBlockChain(NetworkParameters params,
                            FullPrunedBlockStore blockStore)
                     throws BlockStoreException

Constructs a block chain connected to the given store.

Throws:

BlockStoreException

FullPrunedBlockChain

public FullPrunedBlockChain(NetworkParameters params,
                            java.util.List<Wallet> listeners,
                            FullPrunedBlockStore blockStore)
                     throws BlockStoreException

Constructs a block chain connected to the given list of wallets and a store.

Throws:

BlockStoreException

Method Detail

addToBlockStore

protected StoredBlock addToBlockStore(StoredBlock storedPrev,
                                      Block header,
                                      TransactionOutputChanges txOutChanges)
                               throws BlockStoreException,
                                      VerificationException

Description copied from class: AbstractBlockChain

Adds/updates the given StoredBlock with the block store. This version is used when the transactions have already been verified to properly spend txOutputChanges.

Specified by:

addToBlockStore in class AbstractBlockChain

Parameters:

storedPrev - The StoredBlock which immediately precedes block.

header - The StoredBlock to add/update.

txOutChanges - The total sum of all changes made by this block to the set of open transaction outputs (from a call to connectTransactions), if in fully verifying mode (null otherwise).

Returns:

the newly created StoredBlock

Throws:

BlockStoreException - if a failure occurs while storing a block

VerificationException - if the block is invalid

addToBlockStore

protected StoredBlock addToBlockStore(StoredBlock storedPrev,
                                      Block block)
                               throws BlockStoreException,
                                      VerificationException

Description copied from class: AbstractBlockChain

Adds/updates the given Block with the block store. This version is used when the transactions have not been verified.

Specified by:

addToBlockStore in class AbstractBlockChain

Parameters:

storedPrev - The StoredBlock which immediately precedes block.

block - The Block to add/update.

Returns:

the newly created StoredBlock

Throws:

BlockStoreException - if a failure occurs while storing a block

VerificationException - if the block is invalid

rollbackBlockStore

protected void rollbackBlockStore(int height)
                           throws BlockStoreException

Description copied from class: AbstractBlockChain

Rollback the block store to a given height. This is currently only supported by BlockChain instances.

Specified by:

rollbackBlockStore in class AbstractBlockChain

Parameters:

height - height to roll back to

Throws:

BlockStoreException - if the operation fails or is unsupported.

shouldVerifyTransactions

protected boolean shouldVerifyTransactions()

Description copied from class: AbstractBlockChain

Whether or not we are maintaining a set of unspent outputs and are verifying all transactions. Also indicates that all calls to add() should provide a block containing transactions

Specified by:

shouldVerifyTransactions in class AbstractBlockChain

Returns:

true if we are verifying all transactions

setRunScripts

public void setRunScripts(boolean value)

Whether or not to run scripts whilst accepting blocks (i.e. checking signatures, for most transactions). If you're accepting data from an untrusted node, such as one found via the P2P network, this should be set to true (which is the default). If you're downloading a chain from a node you control, script execution is redundant because you know the connected node won't relay bad data to you. In that case it's safe to set this to false and obtain a significant speedup.

connectTransactions

protected TransactionOutputChanges connectTransactions(int height,
                                                       Block block)
                                                throws VerificationException,
                                                       BlockStoreException

Description copied from class: AbstractBlockChain

Connect each transaction in block.transactions, verifying them as we go and removing spent outputs If an error is encountered in a transaction, no changes should be made to the underlying BlockStore. and a VerificationException should be thrown. Only called if(shouldVerifyTransactions())

Specified by:

connectTransactions in class AbstractBlockChain

Parameters:

height - block height to attach at

block - block to connect

Returns:

The full set of all changes made to the set of open transaction outputs.

Throws:

VerificationException - if an attempt was made to spend an already-spent output, or if a transaction incorrectly solved an output script.

BlockStoreException - if the block store had an underlying error.

connectTransactions

protected TransactionOutputChanges connectTransactions(StoredBlock newBlock)
                                                throws VerificationException,
                                                       BlockStoreException,
                                                       PrunedException

Used during reorgs to connect a block previously on a fork

Specified by:

connectTransactions in class AbstractBlockChain

Parameters:

newBlock - block to load

Returns:

The full set of all changes made to the set of open transaction outputs.

Throws:

VerificationException - if an attempt was made to spend an already-spent output, or if a transaction incorrectly solved an output script.

BlockStoreException - if the block store had an underlying error or newBlock does not exist in the block store at all.

PrunedException - if newBlock does not exist as a StoredUndoableBlock in the block store.

disconnectTransactions

protected void disconnectTransactions(StoredBlock oldBlock)
                               throws PrunedException,
                                      BlockStoreException

This is broken for blocks that do not pass BIP30, so all BIP30-failing blocks which are allowed to fail BIP30 must be checkpointed.

Specified by:

disconnectTransactions in class AbstractBlockChain

Parameters:

oldBlock - block to disconnect

Throws:

PrunedException - if block does not exist as a StoredUndoableBlock in the block store.

BlockStoreException - if the block store had an underlying error or block does not exist in the block store at all.

doSetChainHead

protected void doSetChainHead(StoredBlock chainHead)
                       throws BlockStoreException

Description copied from class: AbstractBlockChain

Called before setting chain head in memory. Should write the new head to block store and then commit any database transactions that were started by disconnectTransactions/connectTransactions.

Specified by:

doSetChainHead in class AbstractBlockChain

Parameters:

chainHead - chain head to set

Throws:

BlockStoreException - if a failure occurs while storing a block

notSettingChainHead

protected void notSettingChainHead()
                            throws BlockStoreException

Description copied from class: AbstractBlockChain

Called if we (possibly) previously called disconnectTransaction/connectTransactions, but will not be calling preSetChainHead as a block failed verification. Can be used to abort database transactions that were started by disconnectTransactions/connectTransactions.

Specified by:

notSettingChainHead in class AbstractBlockChain

Throws:

BlockStoreException - if a failure occurs while storing a block

getStoredBlockInCurrentScope

protected StoredBlock getStoredBlockInCurrentScope(Sha256Hash hash)
                                            throws BlockStoreException

Description copied from class: AbstractBlockChain

For a standard BlockChain, this should return blockStore.get(hash), for a FullPrunedBlockChain blockStore.getOnceUndoableStoredBlock(hash)

Specified by:

getStoredBlockInCurrentScope in class AbstractBlockChain

Parameters:

hash - hash of block to fetch

Returns:

block with matching hash

Throws:

BlockStoreException - if a failure occurs while storing a block