class

UdpSocket

class UdpSocket : Obj

UdpSocket manages a UDP/IP datagram endpoint.

constructors make

Make a new unbound UDP socket

methods disconnect

Disconnect this socket from its remote address

receive

Receive a packet on this socket's bound local address

localPort

Get the bound local port or null if unbound

isConnected

Is this socket "connected" to a specific remote host

remotePort

Get the remote port or null if not connected to a specific end point

bind

Bind this socket to the specified local address

isClosed

Is this socket closed

isBound

Is this socket bound to a local address and port

options

Access the SocketOptions used to tune this socket

close

Close this socket

config

Get the socket configuration for this socket

localAddr

Get the bound local address or null if unbound

send

Send the packet to its specified remote endpoint

connect

Connect this socket to the specified address and port

remoteAddr

Get the remote address or null if not connected to a specific end point

bind This bind(IpAddr? addr, Int? port)

Bind this socket to the specified local address. If addr is null then the default IpAddr for the local host is selected. If port is null an ephemeral port is selected. Throw IOErr if the port is already bound or the bind fails. Return this.

close Bool close()

Close this socket. This method is guaranteed to never throw an IOErr. Return true if the socket was closed successfully or false if the socket was closed abnormally.

config SocketConfig config()

Get the socket configuration for this socket.

connect This connect(IpAddr addr, Int port)

Connect this socket to the specified address and port. Once connected packets may only be send to the remote using this socket.

disconnect This disconnect()

Disconnect this socket from its remote address. Do nothing if not connected. Return this.

isBound Bool isBound()

Is this socket bound to a local address and port.

isClosed Bool isClosed()

Is this socket closed.

isConnected Bool isConnected()

Is this socket "connected" to a specific remote host. Since UDP is not session oriented, connected just means we've used connect() to predefine the remote address where we want to send packets.

localAddr IpAddr? localAddr()

Get the bound local address or null if unbound.

localPort Int? localPort()

Get the bound local port or null if unbound.

make new make(SocketConfig config)

Make a new unbound UDP socket. The socket will be configured using the given socket configuration. The following configuration applies to UDP sockets:

options @Deprecated { msg="Use SocketConfig" }
SocketOptions options()

Access the SocketOptions used to tune this socket. The following options apply to UdpSockets:

  • broadcast
  • receiveBufferSize
  • sendBufferSize
  • reuseAddr
  • receiveBufferSize
  • trafficClass Accessing other option fields will throw UnsupportedErr.

receive UdpPacket receive(UdpPacket? packet)

Receive a packet on this socket's bound local address. The resulting packet is filled in with the sender's address and port. This method blocks until a packet is received. If this socket's receiveTimeout option is configured, then receive will timeout with an IOErr.

The packet data is read into the Buf starting at it's current position. The buffer is not grown - at most Buf.capacity bytes are received. If the received message is longer than the packet's capacity then the message is silently truncated (weird Java behavior). Upon return the Buf size and position are updated to reflect the bytes read. Use Buf.flip to ready the buffer to read from start. If packet is null, then a new packet is created with a capacity of 1kb. The packet data must always be a memory backed buffer.

remoteAddr IpAddr? remoteAddr()

Get the remote address or null if not connected to a specific end point.

remotePort Int? remotePort()

Get the remote port or null if not connected to a specific end point.

send Void send(UdpPacket packet)

Send the packet to its specified remote endpoint. If this is socket is connected to a specific remote address, then the packet's address and port must be null or ArgErr is thrown. Throw IOErr on error.

The number of bytes sent is buf.remaining; upon return the buf is drained and position is advanced.

Haxall 4.0.5 ∙ 24-Feb-2026 14:33 EST