Module net
This module provides support for networking using
TCP and UDP sockets. A socket represents a connection between a
client and a server program over a network. The underlying native
binding is provided by the java.net package.
Example
// A simple TCP server
const io = require('io');
const net = require('net');
const server = new net.ServerSocket();
server.bind('127.0.0.1', 6789);
const socket = server.accept();
const stream = new io.TextStream(socket.getStream(), {
'charset': 'US-ASCII'
});
let line;
do {
// Read one line from the client
line = stream.readLine();
console.log(line);
// Write back to the client
stream.writeLine("Received: " + line);
} while (line.indexOf("END") < 0);
stream.close();
socket.close();
server.close();Class DatagramSocket
Instance Methods
- bind(host, port)
- close()
- connect(host, port)
- disconnect()
- getTimeout()
- isBound()
- isClosed()
- isConnected()
- localAddress()
- receive(length, buffer)
- receiveFrom(length, buffer)
- remoteAddress()
- send(data)
- sendTo(host, port, data)
- setTimeout(timeout)
Class ServerSocket
Instance Methods
- accept()
- bind(host, port)
- close()
- getTimeout()
- isBound()
- isClosed()
- localAddress()
- setTimeout(timeout)
Class Socket
Instance Methods
- bind(host, port)
- close()
- connect(host, port, [timeout])
- getStream()
- getTimeout()
- isBound()
- isClosed()
- isConnected()
- localAddress()
- remoteAddress()
- setTimeout(timeout)
DatagramSocket ()
The DatagramSocket class is used to create a UDP socket.
DatagramSocket.prototype. bind (host, port)
Binds the socket to a local address and port. If address or port are omitted the system will choose a local address and port to bind the socket.
Parameters
| String | host | address (interface) to which the socket will be bound. |
| Number | port | port number to bind the socket to. |
DatagramSocket.prototype. close ()
Close the socket immediately
DatagramSocket.prototype. connect (host, port)
Connect the socket to a remote address. If a DatagramSocket is connected, it may only send data to and receive data from the given address. By default DatagramSockets are not connected.
Parameters
| String | host | IP address or hostname |
| Number | port | port number or service name |
DatagramSocket.prototype. disconnect ()
Disconnects the socket.
DatagramSocket.prototype. getTimeout ()
Return the current timeout of this DatagramSocket. A value of zero implies that timeout is disabled, i.e. receive() will never time out.
Returns
| Number | the current timeout |
DatagramSocket.prototype. isBound ()
Returns whether this socket is bound to an address.
Returns
| Boolean | true if the socket has been bound to an address |
DatagramSocket.prototype. isClosed ()
Returns whether the socket is closed or not.
Returns
| Boolean | true if the socket has been closed |
DatagramSocket.prototype. isConnected ()
Returns whether the socket is connected or not.
Returns
| Boolean | true if the socket has been connected to a remote address |
DatagramSocket.prototype. localAddress ()
Get the local address to which this socket is bound. This returns an
object with a property address containing the IP address as string
and a property port containing the port number, e.g.
{address: '127.0.0.1', port: 8080}.
Returns
| Object | an address descriptor |
DatagramSocket.prototype. receive (length, buffer)
Receive a datagram packet from this socket. This method does not return the sender's IP address, so it is meant to be in conjunction with connect().
Parameters
| Number | length | the maximum number of bytes to receive |
| ByteArray | buffer | optional buffer to store bytes in |
Returns
| ByteArray | the received data |
DatagramSocket.prototype. receiveFrom (length, buffer)
Receive a datagram packet from this socket. This method returns an object with the following properties:
- address: the sender's IP address as string
- port: the sender's port number
- data: the received data
Parameters
| Number | length | the maximum number of bytes to receive |
| ByteArray | buffer | optional buffer to store bytes in |
Returns
| Object | the received packet |
DatagramSocket.prototype. remoteAddress ()
Get the remote address to which this socket is connected. This returns an
object with a property address containing the IP address as string
and a property port containing the port number, e.g.
{address: '127.0.0.1', port: 8080}.
Returns
| Object | an address descriptor |
DatagramSocket.prototype. send (data)
Send a datagram packet from this socket. This method does not allow the specify the recipient's IP address, so it is meant to be in conjunction with connect().
Parameters
| Binary | data | the data to send |
DatagramSocket.prototype. sendTo (host, port, data)
Send a datagram packet from this socket to the specified address.
Parameters
| String | host | the IP address of the recipient |
| Number | port | the port number |
| Binary | data | the data to send |
DatagramSocket.prototype. setTimeout (timeout)
Enable/disable timeout with the specified timeout, in milliseconds. With this option set to a non-zero timeout, a call to receive() for this DatagramSocket will block for only this amount of time.
Parameters
| Number | timeout | timeout in milliseconds |
ServerSocket ()
This class implements a server socket. Server sockets wait for requests coming in over the network.
ServerSocket.prototype. accept ()
Listens for a connection to be made to this socket and returns a new Socket object. The method blocks until a connection is made.
Returns
| Socket | a newly connected socket object |
ServerSocket.prototype. bind (host, port)
Binds the socket to a local address and port. If address or port are omitted the system will choose a local address and port to bind the socket.
Parameters
| String | host | address (interface) to which the socket will be bound. |
| Number | port | port number to bind the socket to. |
ServerSocket.prototype. close ()
Close the socket immediately
ServerSocket.prototype. getTimeout ()
Return the current timeout of this ServerSocket. A value of zero implies that timeout is disabled, i.e. accept() will never time out.
Returns
| Number | the current timeout |
ServerSocket.prototype. isBound ()
Returns whether this socket is bound to an address.
Returns
| Boolean | true if the socket has been bound to an address |
ServerSocket.prototype. isClosed ()
Returns whether the socket is closed or not.
Returns
| Boolean | true if the socket has been closed |
ServerSocket.prototype. localAddress ()
Get the local address to which this socket is bound. This returns an
object with a property address containing the IP address as string
and a property port containing the port number, e.g.
{address: '127.0.0.1', port: 8080}
Returns
| Object | an address descriptor |
ServerSocket.prototype. setTimeout (timeout)
Enable/disable timeout with the specified timeout, in milliseconds. With this option set to a non-zero timeout, a call to accept() for this ServerSocket will block for only this amount of time.
Parameters
| Number | timeout | timeout in milliseconds |
Socket ()
The Socket class is used to create a TCP socket. Newly created sockets must be connected to a remote address before being able to send and receive data.
Socket.prototype. bind (host, port)
Binds the socket to a local address and port. If address or port are omitted the system will choose a local address and port to bind the socket.
Parameters
| String | host | address (interface) to which the socket will be bound. |
| Number | port | port number to bind the socket to. |
Socket.prototype. close ()
Close the socket immediately
Socket.prototype. connect (host, port, [timeout])
Initiate a connection on a socket. Connect to a remote port on the specified host with a connection timeout. Throws an exception in case of failure.
Parameters
| String | host | IP address or hostname |
| Number | port | port number or service name |
| Number | [timeout] | optional timeout value in milliseconds |
Socket.prototype. getStream ()
Get the I/O stream for this socket.
Returns
| Stream | a binary stream |
See
Socket.prototype. getTimeout ()
Return the current timeout of this Socket. A value of zero implies that timeout is disabled, i.e. read() will never time out.
Returns
| Number | the current timeout |
Socket.prototype. isBound ()
Returns whether this socket is bound to an address.
Returns
true if the socket has been bound to an address |
Socket.prototype. isClosed ()
Returns whether the socket is closed or not.
Returns
true if the socket has been closed |
Socket.prototype. isConnected ()
Returns whether the socket is connected or not.
Returns
true if the socket has been connected to a remote address |
Socket.prototype. localAddress ()
Get the local address to which this socket is bound. This returns an
object with a property address containing the IP address as string
and a property port containing the port number, e.g.
{address: '127.0.0.1', port: 8080}.
Returns
| Object | an address descriptor |
Socket.prototype. remoteAddress ()
Get the remote address to which this socket is connected. This returns an
object with a property address containing the IP address as string
and a property port containing the port number, e.g.
{address: '127.0.0.1', port: 8080}.
Returns
| Object | an address descriptor |
Socket.prototype. setTimeout (timeout)
Enable/disable timeout with the specified timeout, in milliseconds. With this option set to a non-zero timeout, a read() on this socket's stream will block for only this amount of time.
Parameters
| Number | timeout | timeout in milliseconds |