As per work done by szisti in PR#45:
Extracted MessageException from inside Message into its own class.
Extracted MessageType from inside Message into its own class.
Converted reflection-based Message.fromByteBuffer method call to non-reflection, functional interface, method-reference.
This should have minor performance improvement but stronger method signature and type enforcement, as well as better IDE integration.
Message.fromByteBuffer method 'contract' tightened up to:
1. throw BufferUnderflowException if there are not enough bytes to deserialize message
2. throw MessageException if bytes contain invalid data
3. should not return null
Message.toData method 'contract' tightened up to:
1. return null if the message has no payload to serialize
2. throw IOException directly - no need to try-catch in each subclass
Several Message-subclass fields now marked 'final' as per IDE suggestion.
Several Message-subclass fromByteBuffer() method signatures have changed 'throws' list.
Several bytes.remaining() != some-value changed to bytes.remaining() < some-value as per new contract.
Some bytes.remaining() checks removed for fixed-length messages because we can rely on ByteBuffer throwing BufferUnderflowException.
Some bytes.remaining() checks retained for variable-length messages, or messages that read a large amount of data, to prevent wasted memory allocations.
Other minor tidying up
Temporarily increase sleep from 1ms to 100ms when waiting for outgoing socket buffer to empty.
Real fix is to rewrite using an outgoing message queue and OP_WRITE interest op.
De-register a peer's socket channel OP_READ interest op when producing a ChannelTask for that peer.
This should prevent duplicate ChannelTasks for the same peer.
Re-register OP_READ once node has read from peer's channel.
When node has reached max connections, Network will ignore pending incoming connections by:
1. not calling accept()
2. de-registering OP_ACCEPT 'interest op' on the listen socket's channel
When a peer disconnects, Network might re-register OP_ACCEPT interest op on listen socket.
Slight reworking of EPC to simplify when producer can block
and generally make some of the conditional code more readable.
Improved logging with task class names and logging level editable during runtime!
Use /peer/enginestats?newLoggingLevel=DEBUG (or TRACE or back to INFO) to change.
This is currently for name registration transactions only, but can be adapted (or duplicated) for other transaction types when needed.
Note: this switches from a greater-than (>) to a greater-than-or-equal (>=) timestamp comparison, as it makes more sense this way. It shouldn't affect the previous transition since there were no REGISTER_NAME transactions at that exact timestamp.
Adapted from code originally written by catbref from before genesis, and essentially prevents syncing backwards. This needs significant testing on testnet.
It is quite likely that existing resources with both metadata and an empty chunks array will need to be republished, because this bug may have led to incorrect file deletions.
