org.bitcoinj.core

Class EmptyMessage

java.lang.Object

org.bitcoinj.core.Message

org.bitcoinj.core.EmptyMessage

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

GetAddrMessage, UnknownMessage, VersionAck

public abstract class EmptyMessage
extends Message

Parent class for header only messages that don't have a payload. Currently this includes getaddr, verack and special bitcoinj class UnknownMessage.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.bitcoinj.core.Message

Message.LazyParseException

Field Summary

Fields inherited from class org.bitcoinj.core.Message

checksum, cursor, length, MAX_SIZE, offset, params, parsed, parseLazy, parseRetain, payload, protocolVersion, recached, UNKNOWN_LENGTH

Constructor Summary

Constructors

Constructor and Description
EmptyMessage()
EmptyMessage(NetworkParameters params)
EmptyMessage(NetworkParameters params, byte[] payload, int offset)

Method Summary

Modifier and Type	Method and Description
byte[]	bitcoinSerialize() Returns a copy of the array returned by Message.unsafeBitcoinSerialize(), which is safe to mutate.
protected void	bitcoinSerializeToStream(OutputStream stream) Serializes this message to the provided stream.
void	ensureParsed() In lazy parsing mode access to getters and setters may throw an unchecked LazyParseException.
int	getMessageSize() This should be overridden to extract correct message size in the case of lazy parsing.
protected void	parseLite() Perform the most minimal parse possible to calculate the length of the message payload.

Methods inherited from class org.bitcoinj.core.Message

adjustLength, bitcoinSerialize, getHash, getParams, isCached, isParsed, isRecached, maybeParse, unCache, unsafeBitcoinSerialize

Methods inherited from class java.lang.Object

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

Constructor Detail

EmptyMessage

public EmptyMessage()

EmptyMessage

public EmptyMessage(NetworkParameters params)

EmptyMessage

public EmptyMessage(NetworkParameters params,
                    byte[] payload,
                    int offset)
             throws ProtocolException

Throws:

ProtocolException

Method Detail

bitcoinSerializeToStream

protected final void bitcoinSerializeToStream(OutputStream stream)
                                       throws IOException

Description copied from class: Message

Serializes this message to the provided stream. If you just want the raw bytes use bitcoinSerialize().

Throws:

IOException

getMessageSize

public int getMessageSize()

Description copied from class: Message

This should be overridden to extract correct message size in the case of lazy parsing. Until this method is implemented in a subclass of ChildMessage lazy parsing may have no effect. This default implementation is a safe fall back that will ensure it returns a correct value by parsing the message.

Overrides:

getMessageSize in class Message

parseLite

protected void parseLite()
                  throws ProtocolException

Description copied from class: Message

Perform the most minimal parse possible to calculate the length of the message payload. This is only required for subclasses of ChildMessage as root level messages will have their length passed into the constructor.

Implementations should adhere to the following contract: If parseLazy = true the 'length' field must be set before returning. If parseLazy = false the length field must be set either within the parseLite() method OR the parse() method. The overriding requirement is that length must be set to non UNKNOWN_MESSAGE value by the time the constructor exits.

Specified by:

parseLite in class Message

Throws:

ProtocolException

ensureParsed

public void ensureParsed()
                  throws ProtocolException

Description copied from class: Message

In lazy parsing mode access to getters and setters may throw an unchecked LazyParseException. If guaranteed safe access is required this method will force parsing to occur immediately thus ensuring LazyParseExeption will never be thrown from this Message. If the Message contains child messages (e.g. a Block containing Transaction messages) this will not force child messages to parse.

This could be overidden for Transaction and it's child classes to ensure the entire tree of Message objects is parsed.

Overrides:

ensureParsed in class Message

Throws:

ProtocolException

bitcoinSerialize

public byte[] bitcoinSerialize()

Description copied from class: Message

Returns a copy of the array returned by Message.unsafeBitcoinSerialize(), which is safe to mutate. If you need extra performance and can guarantee you won't write to the array, you can use the unsafe version.

Overrides:

bitcoinSerialize in class Message

Returns:

a freshly allocated serialized byte array