Package org.bitcoinj.crypto

Class ChildNumber

  • All Implemented Interfaces:
    java.lang.Comparable<ChildNumber>
    public class ChildNumber
extends java.lang.Object
implements java.lang.Comparable<ChildNumber>

    This is just a wrapper for the i (child number) as per BIP 32 with a boolean getter for the most significant bit and a getter for the actual 0-based child number. A List of these forms a path through a DeterministicHierarchy. This class is immutable.

    • Field Detail

      • HARDENED_BIT

        public static final int HARDENED_BIT
        The bit that's set in the child number to indicate whether this key is "hardened". Given a hardened key, it is not possible to derive a child public key if you know only the hardened public key. With a non-hardened key this is possible, so you can derive trees of public keys given only a public parent, but the downside is that it's possible to leak private keys if you disclose a parent public key and a child private key (elliptic curve maths allows you to work upwards).
        See Also:
        Constant Field Values

      • ZERO_HARDENED

        public static final ChildNumber ZERO_HARDENED

      • ONE_HARDENED

        public static final ChildNumber ONE_HARDENED

      • PURPOSE_BIP44

        public static final ChildNumber PURPOSE_BIP44

      • PURPOSE_BIP49

        public static final ChildNumber PURPOSE_BIP49

      • PURPOSE_BIP84

        public static final ChildNumber PURPOSE_BIP84

      • PURPOSE_BIP86

        public static final ChildNumber PURPOSE_BIP86

      • COINTYPE_BTC

        public static final ChildNumber COINTYPE_BTC

      • COINTYPE_TBTC

        public static final ChildNumber COINTYPE_TBTC

      • CHANGE_RECEIVING

        public static final ChildNumber CHANGE_RECEIVING

      • CHANGE_CHANGE

        public static final ChildNumber CHANGE_CHANGE

    • Constructor Detail

      • ChildNumber

        public ChildNumber​(int childNumber,
                   boolean isHardened)

      • ChildNumber

        public ChildNumber​(int i)

    • Method Detail

      • getI

        public int getI()
        Returns the uint32 encoded form of the path element, including the most significant bit.

      • i

        public int i()
        Returns the uint32 encoded form of the path element, including the most significant bit.

      • isHardened

        public boolean isHardened()

      • num

        public int num()
        Returns the child number without the hardening bit set (i.e. index in that part of the tree).

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object

      • 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

      • compareTo

        public int compareTo​(ChildNumber other)
        Specified by:
        compareTo in interface java.lang.Comparable<ChildNumber>