net.kwfgrid.gwes.uiproxy
Class UIProxyImpl

java.lang.Object
  net.kwfgrid.gwes.uiproxy.UIProxyImpl

All Implemented Interfaces:

UIProxy

public class UIProxyImpl
extends Object
implements UIProxy

The UIProxy. Facade for buffers, subscription handler and leasing system. The current implementation has no sophisticating synchronization management. This may lead to performance issues with multiple clients and buffers and should be fixed in the future.

Nested Class Summary

protected class

UIProxyImpl.Lease

Field Summary

protected BufferFactory	_bfact
protected HashMapOfMaps	_clients clientid -> bufferids -> buffer.
protected MessageCodec	_codec
protected HashMap	_leases clientid -> lease
protected int	_leasetime
protected SubscriptionHandler	_shandler
protected HashMapOfMaps	_subscriptions clientid -> bufferids -> subscription
static int	DEFAULT_LEASE_TIME

Constructor Summary

UIProxyImpl(BufferFactory bfact, MessageCodec codec, SubscriptionHandler shandler)

Method Summary

void	disposeBuffer(String clientid, String bufferid) Dispose a buffer.
void	disposeClient(String clientid) Dispose a whole client.
protected Buffer	getBuffer(String clientid, String bufferid)
int	getLeaseTime()
String[]	poll(String clientid, String bufferid) Poll all buffered notifications for the specified client and buffer.
void	renewLease(String clientid) Renew the lease for the specified client.
void	setBufferProperty(String clientid, String bufferid, String key, String value) Set a property of a buffer.
void	setLeaseTime(int time)
String	subscribe(String clientid, String subscription, String buffertype, String[] propkeys, String[] propvalues) Subscribe for messages at a publisher.
protected void	timeout(String clientid) Called if a lease has timed out.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_LEASE_TIME

public static final int DEFAULT_LEASE_TIME

See Also:

Constant Field Values

_clients

protected HashMapOfMaps _clients

clientid -> bufferids -> buffer.

_subscriptions

protected HashMapOfMaps _subscriptions

clientid -> bufferids -> subscription

_leases

protected HashMap _leases

clientid -> lease

_bfact

protected BufferFactory _bfact

_shandler

protected SubscriptionHandler _shandler

_codec

protected MessageCodec _codec

_leasetime

protected int _leasetime

Constructor Detail

UIProxyImpl

public UIProxyImpl(BufferFactory bfact,
                   MessageCodec codec,
                   SubscriptionHandler shandler)

Method Detail

setLeaseTime

public void setLeaseTime(int time)

getLeaseTime

public int getLeaseTime()

getBuffer

protected Buffer getBuffer(String clientid,
                           String bufferid)

subscribe

public String subscribe(String clientid,
                        String subscription,
                        String buffertype,
                        String[] propkeys,
                        String[] propvalues)
                 throws SubscriptionFailed

Subscribe for messages at a publisher. This will instantiate a buffer which stores the notification provided by the publisher. The specification of the subuscription must conform to the format which is defined by the SubscriptionHandler of the UIProxy.

Specified by:

subscribe in interface UIProxy

Parameters:

clientid - The UUID of the client.

subscription - Specification of the subscription.

buffertype - The type of the buffer to be created.

propkeys - The keys of the properties of the buffer, same index as propvalues.

propvalues - The values of the properties of the buffer, same index as propkeys.

Returns:

The UUID of the newly created buffer. Needed to poll notifications from that buffer.

Throws:

SubscriptionFailed - If the subscription failed.

renewLease

public void renewLease(String clientid)

Renew the lease for the specified client. If the client is unknown the request is silently discarded.

Specified by:

renewLease in interface UIProxy

Parameters:

clientid - The UUID of the client.

setBufferProperty

public void setBufferProperty(String clientid,
                              String bufferid,
                              String key,
                              String value)
                       throws BufferException

Set a property of a buffer. Calling this method will also renew the lease for the specified client. If the client is not the creator of the buffer, this method will silently discard the request.

Specified by:

setBufferProperty in interface UIProxy

Parameters:

clientid - The UUID of the client.

bufferid - The UUID of the buffer.

key - The name of the property.

value - The value of the property

Throws:

BufferException - If an exception occured when setting the property.

disposeBuffer

public void disposeBuffer(String clientid,
                          String bufferid)

Dispose a buffer. Calling this method will also renew the lease for the specified client. If the client is not the creator of the buffer, this method will silently discard the request.

Specified by:

disposeBuffer in interface UIProxy

Parameters:

clientid - The UUID of the client.

bufferid - The UUID of the buffer.

disposeClient

public void disposeClient(String clientid)

Dispose a whole client. This will free all resources associated with the client. If the client is unknown the request will be silently discarded.

Specified by:

disposeClient in interface UIProxy

Parameters:

clientid - The UUID of the client.

timeout

protected void timeout(String clientid)

Called if a lease has timed out. Disposes the client.

poll

public String[] poll(String clientid,
                     String bufferid)
              throws CodecException,
                     BufferException,
                     UnknownClientException,
                     UnknownBufferException

Poll all buffered notifications for the specified client and buffer. Calling this method will also renew the lease for the specified client. If the client is not the creator of the buffer, this method will silently discard the request and return an empty collection.

Specified by:

poll in interface UIProxy

Returns:

A collection of all buffered notifications from the specified buffer.

Throws:

BufferException - If a exception occured at the buffer when handling a message. In that case the client will have to create a new Buffer.

UnknownClientException - If the specified client is unknown to the UIProxy. This may also happen if the lease has timed out for the specified client.

UnknownBufferException - If the specified buffer is unknown to the UIProxy. This may also happen if the buffer previously encountered a BufferException. specified client.

CodecException