lib.easyjava.net.udp

Class UDPListener<R extends java.io.Serializable>

java.lang.Object

lib.easyjava.net.udp.UDPListener<R>

Type Parameters:

R - the type to receive over UDP

public class UDPListener<R extends java.io.Serializable>
extends java.lang.Object

Receives objects over UDP. Use UDPSender to send them.

Author:

Rob Rua (robrua@alumni.cmu.edu)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	UDPListener.UDPMessage<R extends java.io.Serializable> UDP Packets received will be broken down into these messages detailing where the packet came from and what was in it.

Constructor Summary

Constructors

Constructor and Description
UDPListener(int port) A Listener created with this constructor will fail when an unexpected type is received.
UDPListener(int port, java.lang.Class<R> receivingClass) A Listener created with this constructor will ignore any unexpected types received.

Method Summary

Modifier and Type	Method and Description
void	close() Closes the listener
UDPListener.UDPMessage<R>	receive() Receives a message over UDP.
UDPListener.UDPMessage<R>	receive(long timeout, java.util.concurrent.TimeUnit unit) Receives a message over UDP.
boolean	receiveWillBlock() Returns whether a call to receive() will block to wait on new data or not

Methods inherited from class java.lang.Object

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

Constructor Detail

UDPListener

public UDPListener(int port)
            throws java.net.SocketException

A Listener created with this constructor will fail when an unexpected type is received.

Parameters:

port - the port to listen on

Throws:

java.net.SocketException - if the listener could not be opened

UDPListener

public UDPListener(int port,
                   java.lang.Class<R> receivingClass)
            throws java.net.SocketException

A Listener created with this constructor will ignore any unexpected types received.

Parameters:

port - the port to listen on

receivingClass - the class of object that will be received by this manager. Required to circumvent Java generics type erasure.

Throws:

java.net.SocketException - if the listener could not be opened

Method Detail

close

public void close()

Closes the listener

receive

public UDPListener.UDPMessage<R> receive()
                                  throws java.lang.InterruptedException

Receives a message over UDP. Will block until something is sent through or the listener is closed.

Returns:

the message that was received or null if the listener was closed

Throws:

java.lang.InterruptedException - if the waiting was interrupted

receive

public UDPListener.UDPMessage<R> receive(long timeout,
                                         java.util.concurrent.TimeUnit unit)
                                  throws java.lang.InterruptedException

Receives a message over UDP. Will block until something is sent through, the listener is closed, or the specified time has elapsed.

Parameters:

timeout - the amount of time before timeout

unit - the unit of time

Returns:

the message that was received, null if the listener was closed or receive timed out

Throws:

java.lang.InterruptedException - if the waiting was interrupted

receiveWillBlock

public boolean receiveWillBlock()

Returns whether a call to receive() will block to wait on new data or not

Returns:

false if there is existing data in the stream, true if receive() will wait for new data