com.google.bitcoin.core

Class Base58

java.lang.Object

com.google.bitcoin.core.Base58

public class Base58
extends Object

Base58 is a way to encode Bitcoin addresses as numbers and letters. Note that this is not the same base58 as used by Flickr, which you may see reference to around the internet.

You may instead wish to work with VersionedChecksummedBytes, which adds support for testing the prefix and suffix bytes commonly found in addresses.

Satoshi says: why base-58 instead of standard base-64 encoding?

• Don't want 0OIl characters that look the same in some fonts and could be used to create visually identical looking account numbers.
• A string with non-alphanumeric characters is not as easily accepted as an account number.
• E-mail usually won't line-break if there's no punctuation to break at.
• Doubleclicking selects the whole number as one word if it's all alphanumeric.

Field Summary

Fields

Modifier and Type	Field and Description
static char[]	ALPHABET

Constructor Summary

Constructors

Constructor and Description
Base58()

Method Summary

Methods

Modifier and Type	Method and Description
static byte[]	decode(String input)
static byte[]	decodeChecked(String input) Uses the checksum in the last 4 bytes of the decoded data to verify the rest are correct.
static BigInteger	decodeToBigInteger(String input)
static String	encode(byte[] input) Encodes the given bytes in base58.

Methods inherited from class java.lang.Object

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

Field Detail

ALPHABET

public static final char[] ALPHABET

Constructor Detail

Base58

public Base58()

Method Detail

encode

public static String encode(byte[] input)

Encodes the given bytes in base58. No checksum is appended.

decode

public static byte[] decode(String input)
                     throws AddressFormatException

Throws:

AddressFormatException

decodeToBigInteger

public static BigInteger decodeToBigInteger(String input)
                                     throws AddressFormatException

Throws:

AddressFormatException

decodeChecked

public static byte[] decodeChecked(String input)
                            throws AddressFormatException

Uses the checksum in the last 4 bytes of the decoded data to verify the rest are correct. The checksum is removed from the returned data.

Throws:

AddressFormatException - if the input is not base 58 or the checksum does not validate.