Class NetworkParameters

  • Direct Known Subclasses:
    AbstractBitcoinNetParams

    public abstract class NetworkParameters
    extends java.lang.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 Detail

      • ID_MAINNET

        public static final java.lang.String ID_MAINNET
        The string returned by getId() for the main, production network where people trade things.
        See Also:
        Constant Field Values
      • ID_TESTNET

        public static final java.lang.String ID_TESTNET
        The string returned by getId() for the testnet.
        See Also:
        Constant Field Values
      • ID_REGTEST

        public static final java.lang.String ID_REGTEST
        The string returned by getId() for regtest mode.
        See Also:
        Constant Field Values
      • ID_UNITTESTNET

        public static final java.lang.String ID_UNITTESTNET
        Unit test network.
        See Also:
        Constant Field Values
      • PAYMENT_PROTOCOL_ID_MAINNET

        public static final java.lang.String PAYMENT_PROTOCOL_ID_MAINNET
        The string used by the payment protocol to represent the main net.
        See Also:
        Constant Field Values
      • PAYMENT_PROTOCOL_ID_TESTNET

        public static final java.lang.String PAYMENT_PROTOCOL_ID_TESTNET
        The string used by the payment protocol to represent the test net.
        See Also:
        Constant Field Values
      • PAYMENT_PROTOCOL_ID_UNIT_TESTS

        public static final java.lang.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:
        Constant Field Values
      • PAYMENT_PROTOCOL_ID_REGTEST

        public static final java.lang.String PAYMENT_PROTOCOL_ID_REGTEST
        See Also:
        Constant Field Values
      • maxTarget

        protected java.math.BigInteger maxTarget
      • port

        protected int port
      • packetMagic

        protected long packetMagic
      • addressHeader

        protected int addressHeader
      • p2shHeader

        protected int p2shHeader
      • dumpedPrivateKeyHeader

        protected int dumpedPrivateKeyHeader
      • segwitAddressHrp

        protected java.lang.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 java.lang.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 java.lang.String[] dnsSeeds
      • addrSeeds

        protected int[] addrSeeds
      • checkpoints

        protected java.util.Map<java.lang.Integer,​Sha256Hash> checkpoints
      • defaultSerializer

        protected transient volatile MessageSerializer defaultSerializer
      • 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:
        Constant Field Values
      • MAX_COINS

        public static final long MAX_COINS
        The maximum number of coins to be generated
        See Also:
        Constant Field Values
      • MAX_MONEY

        public static final Coin MAX_MONEY
        The maximum money to be generated
    • Constructor Detail

      • NetworkParameters

        protected NetworkParameters()
    • Method Detail

      • getId

        public java.lang.String getId()
        A Java package style string acting as unique ID for these parameters
      • getPaymentProtocolId

        public abstract java.lang.String getPaymentProtocolId()
      • equals

        public boolean equals​(java.lang.Object o)
        Overrides:
        equals in class java.lang.Object
      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class java.lang.Object
      • fromID

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

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

        public int getSpendableCoinbaseDepth()
      • 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 java.lang.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 java.lang.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 java.math.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).
      • getMonetaryFormat

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

        public abstract java.lang.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 java.util.EnumSet<Block.VerifyFlag> getBlockVerificationFlags​(Block block,
                                                                             VersionTally tally,
                                                                             java.lang.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 java.util.EnumSet<Script.VerifyFlag> getTransactionVerificationFlags​(Block block,
                                                                                    Transaction transaction,
                                                                                    VersionTally tally,
                                                                                    java.lang.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.