org.bitcoinj.crypto

Class MnemonicCode

java.lang.Object

org.bitcoinj.crypto.MnemonicCode

public class MnemonicCode
extends Object

A MnemonicCode object may be used to convert between binary seed values and lists of words per the BIP 39 specification

Field Summary

Fields

Modifier and Type	Field and Description
static long	BIP39_STANDARDISATION_TIME_SECS UNIX time for when the BIP39 standard was finalised.
static MnemonicCode	INSTANCE

Constructor Summary

Constructors

Constructor and Description
MnemonicCode() Initialise from the included word list.
MnemonicCode(InputStream wordstream, String wordListDigest) Creates an MnemonicCode object, initializing with words read from the supplied input stream.

Method Summary

Modifier and Type	Method and Description
void	check(List<String> words) Check to see if a mnemonic word list is valid.
List<String>	getWordList() Gets the word list this code uses.
byte[]	toEntropy(List<String> words) Convert mnemonic word list to original entropy value.
List<String>	toMnemonic(byte[] entropy) Convert entropy data to mnemonic word list.
static byte[]	toSeed(List<String> words, String passphrase) Convert mnemonic word list to seed.

Methods inherited from class java.lang.Object

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

Field Detail

BIP39_STANDARDISATION_TIME_SECS

public static long BIP39_STANDARDISATION_TIME_SECS

UNIX time for when the BIP39 standard was finalised. This can be used as a default seed birthday.

INSTANCE

public static MnemonicCode INSTANCE

Constructor Detail

MnemonicCode

public MnemonicCode()
             throws IOException

Initialise from the included word list. Won't work on Android.

Throws:

IOException

MnemonicCode

public MnemonicCode(InputStream wordstream,
                    String wordListDigest)
             throws IOException,
                    IllegalArgumentException

Creates an MnemonicCode object, initializing with words read from the supplied input stream. If a wordListDigest is supplied the digest of the words will be checked.

Throws:

IOException

IllegalArgumentException

Method Detail

getWordList

public List<String> getWordList()

Gets the word list this code uses.

toSeed

public static byte[] toSeed(List<String> words,
                            String passphrase)

Convert mnemonic word list to seed.

toEntropy

public byte[] toEntropy(List<String> words)
                 throws MnemonicException.MnemonicLengthException,
                        MnemonicException.MnemonicWordException,
                        MnemonicException.MnemonicChecksumException

Convert mnemonic word list to original entropy value.

Throws:

MnemonicException.MnemonicLengthException

MnemonicException.MnemonicWordException

MnemonicException.MnemonicChecksumException

toMnemonic

public List<String> toMnemonic(byte[] entropy)
                        throws MnemonicException.MnemonicLengthException

Convert entropy data to mnemonic word list.

Throws:

MnemonicException.MnemonicLengthException

check

public void check(List<String> words)
           throws MnemonicException

Check to see if a mnemonic word list is valid.

Throws:

MnemonicException