# Class ServerSocketFactory

java.lang.Object
javax.net.ServerSocketFactory

Direct Known Subclasses:
  `SSLServerSocketFactory`

public abstract class ServerSocketFactory extends Object
This class creates server sockets. It may be subclassed by other factories, which create particular types of server sockets. This provides a general framework for the addition of public socket-level functionality. It is the server side analogue of a socket factory, and similarly provides a way to capture a variety of policies related to the sockets being constructed.

Like socket factories, server Socket factory instances have methods used to create sockets. There is also an environment specific default server socket factory; frameworks will often use their own customized factory.

Since:
  1.4
See Also:
  - `SocketFactory`

## Constructor Summary

Constructors
Modifier
Constructor
Description
`protected`
`ServerSocketFactory()`
Creates a server socket factory.

## Method Summary

Modifier and Type
Method
Description
`ServerSocket`
`createServerSocket()`
Returns an unbound server socket.
`abstract ServerSocket`
`createServerSocket(int port)`
Returns a server socket bound to the specified port.
`abstract ServerSocket`
`createServerSocket(int port, int backlog)`
Returns a server socket bound to the specified port, and uses the specified connection backlog.
`abstract ServerSocket`
`createServerSocket(int port, int backlog, InetAddress ifAddress)`
Returns a server socket bound to the specified port, with a specified listen backlog and local IP.
`static ServerSocketFactory`
`getDefault()`
Returns a copy of the environment's default socket factory.

### Methods declared in class Object

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

## Constructor Details

### ServerSocketFactory

protected ServerSocketFactory()
Creates a server socket factory.

## Method Details

### getDefault

public static ServerSocketFactory getDefault()
Returns a copy of the environment's default socket factory.

Returns:
  the `ServerSocketFactory`

### createServerSocket

public ServerSocket createServerSocket() throws IOException
Returns an unbound server socket. The socket is configured with the socket options (such as accept timeout) given to this factory.

Returns:
  the unbound socket
Throws:
  `IOException` - if the socket cannot be created
See Also:
  - `ServerSocket.bind(java.net.SocketAddress)`
  - `ServerSocket.bind(java.net.SocketAddress, int)`
  - `ServerSocket()`

### createServerSocket

public abstract ServerSocket createServerSocket(int port) throws IOException
Returns a server socket bound to the specified port. The socket is configured with the socket options (such as accept timeout) given to this factory.

Parameters:
  `port` - the port to listen to
Returns:
  the `ServerSocket`
Throws:
  `IOException` - for networking errors
  `IllegalArgumentException` - if the port parameter is outside the specified range of valid port values, which is between 0 and 65535, inclusive.
See Also:
  - `ServerSocket(int)`

### createServerSocket

public abstract ServerSocket createServerSocket(int port, int backlog) throws IOException
Returns a server socket bound to the specified port, and uses the specified connection backlog. The socket is configured with the socket options (such as accept timeout) given to this factory.

The `backlog` argument must be a positive value greater than 0. If the value passed if equal or less than 0, then the default value will be assumed.

Parameters:
  `port` - the port to listen to
  `backlog` - how many connections are queued
Returns:
  the `ServerSocket`
Throws:
  `IOException` - for networking errors
  `IllegalArgumentException` - if the port parameter is outside the specified range of valid port values, which is between 0 and 65535, inclusive.
See Also:
  - `ServerSocket(int, int)`

### createServerSocket

public abstract ServerSocket createServerSocket(int port, int backlog, InetAddress ifAddress) throws IOException
Returns a server socket bound to the specified port, with a specified listen backlog and local IP.

The `ifAddress` argument can be used on a multi-homed host for a `ServerSocket` that will only accept connect requests to one of its addresses. If `ifAddress` is null, it will accept connections on all local addresses. The socket is configured with the socket options (such as accept timeout) given to this factory.

The `backlog` argument must be a positive value greater than 0. If the value passed if equal or less than 0, then the default value will be assumed.

Parameters:
  `port` - the port to listen to
  `backlog` - how many connections are queued
  `ifAddress` - the network interface address to use
Returns:
  the `ServerSocket`
Throws:
  `IOException` - for networking errors
  `IllegalArgumentException` - if the port parameter is outside the specified range of valid port values, which is between 0 and 65535, inclusive.
See Also:
  - `ServerSocket(int, int, java.net.InetAddress)`