Package org.bitcoinj.core

Class NetworkParameters

java.lang.Object
org.bitcoinj.core.NetworkParameters
Direct Known Subclasses:
AbstractBitcoinNetParams
public abstract class NetworkParameters extends Object

NetworkParameters contains the data needed for working with an instantiation of a Bitcoin chain.

This is an abstract class, concrete instantiations can be found in the params package. There are four: one for the main network (MainNetParams), one for the public test network, and two others that are intended for unit testing and local app development purposes. Although this class contains some aliases for them, you are encouraged to call the static get() methods on each specific params class directly.

  • Field Details

    • ID_MAINNET

      public static final String ID_MAINNET
      The string returned by getId() for the main, production network where people trade things.
      See Also:

    • ID_TESTNET

      public static final String ID_TESTNET
      The string returned by getId() for the testnet.
      See Also:

    • ID_REGTEST

      public static final String ID_REGTEST
      The string returned by getId() for regtest mode.
      See Also:

    • ID_UNITTESTNET

      public static final String ID_UNITTESTNET
      Unit test network.
      See Also:

    • PAYMENT_PROTOCOL_ID_MAINNET

      public static final String PAYMENT_PROTOCOL_ID_MAINNET
      The string used by the payment protocol to represent the main net.
      See Also:

    • PAYMENT_PROTOCOL_ID_TESTNET

      public static final String PAYMENT_PROTOCOL_ID_TESTNET
      The string used by the payment protocol to represent the test net.
      See Also:

    • PAYMENT_PROTOCOL_ID_UNIT_TESTS

      public static final String PAYMENT_PROTOCOL_ID_UNIT_TESTS
      The string used by the payment protocol to represent unit testing (note that this is non-standard).
      See Also:

    • PAYMENT_PROTOCOL_ID_REGTEST

      public static final String PAYMENT_PROTOCOL_ID_REGTEST
      See Also:

    • maxTarget

      protected BigInteger maxTarget

    • port

      protected int port

    • packetMagic

      protected long packetMagic

    • addressHeader

      protected int addressHeader

    • p2shHeader

      protected int p2shHeader

    • dumpedPrivateKeyHeader

      protected int dumpedPrivateKeyHeader

    • segwitAddressHrp

      protected String segwitAddressHrp

    • interval

      protected int interval

    • targetTimespan

      protected int targetTimespan

    • bip32HeaderP2PKHpub

      protected int bip32HeaderP2PKHpub

    • bip32HeaderP2PKHpriv

      protected int bip32HeaderP2PKHpriv

    • bip32HeaderP2WPKHpub

      protected int bip32HeaderP2WPKHpub

    • bip32HeaderP2WPKHpriv

      protected int bip32HeaderP2WPKHpriv

    • majorityEnforceBlockUpgrade

      protected int majorityEnforceBlockUpgrade
      Used to check majorities for block version upgrade

    • majorityRejectBlockOutdated

      protected int majorityRejectBlockOutdated

    • majorityWindow

      protected int majorityWindow

    • id

      protected String id
      See getId(). This may be null for old deserialized wallets. In that case we derive it heuristically by looking at the port number.

    • spendableCoinbaseDepth

      protected int spendableCoinbaseDepth
      The depth of blocks required for a coinbase transaction to be spendable.

    • subsidyDecreaseBlockCount

      protected int subsidyDecreaseBlockCount

    • dnsSeeds

      protected String[] dnsSeeds

    • addrSeeds

      protected int[] addrSeeds

    • httpSeeds

      protected HttpDiscovery.Details[] httpSeeds

    • checkpoints

      protected Map<Integer,Sha256Hash> checkpoints

    • defaultSerializer

      protected transient volatile MessageSerializer defaultSerializer

    • TARGET_TIMESPAN

      public static final int TARGET_TIMESPAN
      See Also:

    • TARGET_SPACING

      public static final int TARGET_SPACING
      See Also:

    • INTERVAL

      public static final int INTERVAL
      See Also:

    • BIP16_ENFORCE_TIME

      public static final int BIP16_ENFORCE_TIME
      Blocks with a timestamp after this should enforce BIP 16, aka "Pay to script hash". This BIP changed the network rules in a soft-forking manner, that is, blocks that don't follow the rules are accepted but not mined upon and thus will be quickly re-orged out as long as the majority are enforcing the rule.
      See Also:

    • MAX_COINS

      public static final long MAX_COINS
      The maximum number of coins to be generated
      See Also:

    • MAX_MONEY

      public static final Coin MAX_MONEY
      The maximum money to be generated

  • Constructor Details

    • NetworkParameters

      protected NetworkParameters()

  • Method Details

    • getId

      public String getId()
      A Java package style string acting as unique ID for these parameters

    • getPaymentProtocolId

      public abstract String getPaymentProtocolId()

    • equals

      public boolean equals(Object o)
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object

    • fromID

      @Nullable public static NetworkParameters fromID(String id)
      Returns the network parameters for the given string ID or NULL if not recognized.

    • fromPmtProtocolID

      @Nullable public static NetworkParameters fromPmtProtocolID(String pmtProtocolId)
      Returns the network parameters for the given string paymentProtocolID or NULL if not recognized.

    • getSpendableCoinbaseDepth

      public int getSpendableCoinbaseDepth()

    • checkDifficultyTransitions

      public abstract void checkDifficultyTransitions(StoredBlock storedPrev, Block next, BlockStore blockStore) throws VerificationException, BlockStoreException
      Throws an exception if the block's difficulty is not correct.
      Throws:
      VerificationException - if the block's difficulty is not correct.
      BlockStoreException

    • passesCheckpoint

      public boolean passesCheckpoint(int height, Sha256Hash hash)
      Returns true if the block height is either not a checkpoint, or is a checkpoint and the hash matches.

    • isCheckpoint

      public boolean isCheckpoint(int height)
      Returns true if the given height has a recorded checkpoint.

    • getSubsidyDecreaseBlockCount

      public int getSubsidyDecreaseBlockCount()

    • getDnsSeeds

      public String[] getDnsSeeds()
      Returns DNS names that when resolved, give IP addresses of active peers.

    • getAddrSeeds

      public int[] getAddrSeeds()
      Returns IP address of active peers.

    • getHttpSeeds

      public HttpDiscovery.Details[] getHttpSeeds()
      Returns discovery objects for seeds implementing the Cartographer protocol. See HttpDiscovery for more info.

    • getGenesisBlock

      public abstract Block getGenesisBlock()

      Genesis block for this chain.

      The first block in every chain is a well known constant shared between all Bitcoin implementations. For a block to be valid, it must be eventually possible to work backwards to the genesis block by following the prevBlockHash pointers in the block headers.

      The genesis blocks for both test and main networks contain the timestamp of when they were created, and a message in the coinbase transaction. It says, "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks".

    • getPort

      public int getPort()
      Default TCP port on which to connect to nodes.

    • getPacketMagic

      public long getPacketMagic()
      The header bytes that identify the start of a packet on this network.

    • getAddressHeader

      public int getAddressHeader()
      First byte of a base58 encoded address. See LegacyAddress. This is the same as acceptableAddressCodes[0] and is the one used for "normal" addresses. Other types of address may be encountered with version codes found in the acceptableAddressCodes array.

    • getP2SHHeader

      public int getP2SHHeader()
      First byte of a base58 encoded P2SH address. P2SH addresses are defined as part of BIP0013.

    • getDumpedPrivateKeyHeader

      public int getDumpedPrivateKeyHeader()
      First byte of a base58 encoded dumped private key. See DumpedPrivateKey.

    • getSegwitAddressHrp

      public String getSegwitAddressHrp()
      Human readable part of bech32 encoded segwit address.

    • getTargetTimespan

      public int getTargetTimespan()
      How much time in seconds is supposed to pass between "interval" blocks. If the actual elapsed time is significantly different from this value, the network difficulty formula will produce a different value. Both test and main Bitcoin networks use 2 weeks (1209600 seconds).

    • allowEmptyPeerChain

      public boolean allowEmptyPeerChain()
      If we are running in testnet-in-a-box mode, we allow connections to nodes with 0 non-genesis blocks.

    • getInterval

      public int getInterval()
      How many blocks pass between difficulty adjustment periods. Bitcoin standardises this to be 2016.

    • getMaxTarget

      public BigInteger getMaxTarget()
      Maximum target represents the easiest allowable proof of work.

    • getBip32HeaderP2PKHpub

      public int getBip32HeaderP2PKHpub()
      Returns the 4 byte header for BIP32 wallet P2PKH - public key part.

    • getBip32HeaderP2PKHpriv

      public int getBip32HeaderP2PKHpriv()
      Returns the 4 byte header for BIP32 wallet P2PKH - private key part.

    • getBip32HeaderP2WPKHpub

      public int getBip32HeaderP2WPKHpub()
      Returns the 4 byte header for BIP32 wallet P2WPKH - public key part.

    • getBip32HeaderP2WPKHpriv

      public int getBip32HeaderP2WPKHpriv()
      Returns the 4 byte header for BIP32 wallet P2WPKH - private key part.

    • getMaxMoney

      public abstract Coin getMaxMoney()
      Returns the number of coins that will be produced in total, on this network. Where not applicable, a very large number of coins is returned instead (i.e. the main coin issue for Dogecoin).

    • getMinNonDustOutput

      @Deprecated public abstract Coin getMinNonDustOutput()
      Deprecated.
      use TransactionOutput.getMinNonDustValue()

    • getMonetaryFormat

      public abstract MonetaryFormat getMonetaryFormat()
      The monetary object for this currency.

    • getUriScheme

      public abstract String getUriScheme()
      Scheme part for URIs, for example "bitcoin".

    • hasMaxMoney

      public abstract boolean hasMaxMoney()
      Returns whether this network has a maximum number of coins (finite supply) or not. Always returns true for Bitcoin, but exists to be overridden for other networks.

    • getDefaultSerializer

      public final MessageSerializer getDefaultSerializer()
      Return the default serializer for this network. This is a shared serializer.
      Returns:
      the default serializer for this network.

    • getSerializer

      public abstract BitcoinSerializer getSerializer(boolean parseRetain)
      Construct and return a custom serializer.

    • getMajorityEnforceBlockUpgrade

      public int getMajorityEnforceBlockUpgrade()
      The number of blocks in the last getMajorityWindow() blocks at which to trigger a notice to the user to upgrade their client, where the client does not understand those blocks.

    • getMajorityRejectBlockOutdated

      public int getMajorityRejectBlockOutdated()
      The number of blocks in the last getMajorityWindow() blocks at which to enforce the requirement that all new blocks are of the newer type (i.e. outdated blocks are rejected).

    • getMajorityWindow

      public int getMajorityWindow()
      The sampling window from which the version numbers of blocks are taken in order to determine if a new block version is now the majority.

    • getBlockVerificationFlags

      public EnumSet<Block.VerifyFlag> getBlockVerificationFlags(Block block, VersionTally tally, Integer height)
      The flags indicating which block validation tests should be applied to the given block. Enables support for alternative blockchains which enable tests based on different criteria.
      Parameters:
      block - block to determine flags for.
      height - height of the block, if known, null otherwise. Returned tests should be a safe subset if block height is unknown.

    • getTransactionVerificationFlags

      public EnumSet<Script.VerifyFlag> getTransactionVerificationFlags(Block block, Transaction transaction, VersionTally tally, Integer height)
      The flags indicating which script validation tests should be applied to the given transaction. Enables support for alternative blockchains which enable tests based on different criteria.
      Parameters:
      block - block the transaction belongs to.
      transaction - to determine flags for.
      height - height of the block, if known, null otherwise. Returned tests should be a safe subset if block height is unknown.

    • getProtocolVersionNum

      public abstract int getProtocolVersionNum(NetworkParameters.ProtocolVersion version)