Let's understand Data Adapter

awadkab

Hello,
I want to know steps to do chat like chat demo .
When I compare it with Hello World tutorial I didn't find class files just jar file in lib folder .

I can understand client side but server side is harder.

After do client side then we must do data adapter,ok.

Do I have to work DataAdapterand metadataAdapter for each application?
what should I write in every one of them?
what is important methods we must write it in each one?

thanks

Sorry for my bad English.

Dario Crivelli

In general, you don't need to write a Metadata Adapter in order to run a simple demo, like the StockListDemo or the Hello World demo, as leaning on the LiteralBasedProvider is enough.
The Metadata Adapter is needed only when the application involves more complex use cases, like:
- user identification;
- handling messages sent by the client.

This is the case for the Chat Demo.
User identification is needed to associate each client to an identity in the chat room;
usually, user indentification involves the notifyUser method;
we kept it simple and used notifyNewSessioninstead, which yields information on the client context that we could use to identify her (this also involves using notifySessionClose ).
Processing client-originated messages is obviously needed, in order to push them to all other clients in the chat room; this involves notifyUserMessage.

The only other important method is modeMayBeAllowed;
In the Chat Demo Metadata Adapter, we lean on the implementation in the base class (LiteralBasedProvider), which requires suitable configuration parameters (look for "item_family" in DOCS-SDKs\sdk_adapter_java\examples\Chat_Adapters\Deployment_LS\Chat\adapters.xml).

All other methods of the Metadata Adapter deal with restrictions on what users can get and should be taken into consideration only for production deployment.

On the Data Adapter side, all methods are important, as they deal with real-time update delivery.
The Chat Demo has the further complication that the Metadata Adapter and the Data Adapter have to communicate to each other, because the real-time updates to be pushed are based on the client-originated messages.

You can deploy the Adapters either as class files or as jars.

awadkab

Thanks for response

Now its not bad but also not good

I think make a some tutorials(step by step ) like Hello World will help us(I wish find book to learn this good service or viedo toturial :Smile_Ab:

ok, yesterday I try make jar file by eclips and after that when I try start server
it give me error like this)

23-Feb-12 16:59:29,187|INFO |LightstreamerLogger.license      |main                       |Checking license file: C:\Lightstreamer\conf\EtWXOcwHsB8VmYn8xEOdZ.lic
23-Feb-12 16:59:30,765|INFO |LightstreamerLogger.license      |main                       |Starting MAC address check
23-Feb-12 16:59:30,796|INFO |LightstreamerLogger.license      |main                       |Found MAC address 00:12:f0:d9:e0:a9
23-Feb-12 16:59:30,796|INFO |LightstreamerLogger.license      |main                       |Found MAC address 00:c0:ca:30:14:6e
23-Feb-12 16:59:30,796|INFO |LightstreamerLogger.license      |main                       |MAC address check successful
23-Feb-12 16:59:30,796|INFO |LightstreamerLogger.license      |main                       |License correctly bound with the following parameter(s):
23-Feb-12 16:59:30,796|INFO |LightstreamerLogger.license      |main                       |        Client ID       : EtWXOcwHsB8VmYn8xEOdZ
23-Feb-12 16:59:30,796|INFO |LightstreamerLogger.license      |main                       |        Mac Address     : 00:c0:ca:30:14:6e
23-Feb-12 16:59:30,796|INFO |LightstreamerLogger.init         |main                       |Lightstreamer Server starting in Moderato edition
23-Feb-12 16:59:30,906|WARN |LightstreamerLogger.monitoring   |main                       |Only minimal JMX management support is available with the current license
23-Feb-12 16:59:30,984|INFO |LightstreamerLogger.init         |main                       |Started JMXMP Connector for JMX on port 9999
23-Feb-12 16:59:30,984|INFO |LightstreamerLogger.init         |main                       |SERVER pool size set by default at 10
23-Feb-12 16:59:31,078|INFO |LightstreamerLogger.init         |Init for DEMO              |Loading Metadata Adapter DEMO
23-Feb-12 16:59:31,093|INFO |LightstreamerLogger.init         |Init for DEMO.MONITOR      |Loading Data Adapter DEMO.MONITOR
23-Feb-12 16:59:31,093|INFO |LightstreamerLogger.init         |Init for DEMO.QUOTE_ADAPTER|Loading Data Adapter DEMO.QUOTE_ADAPTER
23-Feb-12 16:59:31,093|INFO |LightstreamerLogger.init         |Init for DEMO.CHAT_ROOM    |Loading Data Adapter DEMO.CHAT_ROOM
23-Feb-12 16:59:31,093|INFO |LightstreamerLogger.init         | for DEMO.PORTFOLIO_ADAPTER|Loading Data Adapter DEMO.PORTFOLIO_ADAPTER
23-Feb-12 16:59:31,109|ERROR|LightstreamerLogger.init         |Init for DEMO.CHAT_ROOM    |Data Adapter DEMO.CHAT_ROOM init error: java.lang.NoClassDefFoundError: org/apache/log4j/xml/DOMConfigurator
23-Feb-12 16:59:31,187|ERROR|LightstreamerLogger.init         |main                       |Error while loading the Adapters: java.lang.Exception: Unexpected error in Data Adapters initialization
23-Feb-12 16:59:31,187|ERROR|LightstreamerLogger.init         |main                       |Error while loading the Adapters: Unexpected error in Data Adapters initialization
23-Feb-12 16:59:31,187|FATAL|LightstreamerLogger.init         |main                       |Adapters initialization failed
23-Feb-12 16:59:31,187|INFO |LightstreamerLogger.init         |main                       |Exiting.....
23-Feb-12 16:59:31,234|INFO |LightstreamerLogger.init         |Init for DEMO.QUOTE_ADAPTER|Finished loading Data Adapter DEMO.QUOTE_ADAPTER
23-Feb-12 16:59:31,234|INFO |LightstreamerLogger.init         | for DEMO.PORTFOLIO_ADAPTER|Finished loading Data Adapter DEMO.PORTFOLIO_ADAPTER
23-Feb-12 16:59:31,187|INFO |LightstreamerLogger.init         |Init for DEMO.MONITOR      |Finished loading Data Adapter DEMO.MONITOR
23-Feb-12 16:59:31,187|INFO |LightstreamerLogger.init         |t for DEMO.SIMPLE_MESSENGER|Loading Data Adapter DEMO.SIMPLE_MESSENGER
23-Feb-12 16:59:31,281|INFO |LightstreamerLogger.init         |Init for DEMO              |Finished loading Metadata Adapter DEMO
23-Feb-12 16:59:31,281|INFO |LightstreamerLogger.init         |t for DEMO.SIMPLE_MESSENGER|Finished loading Data Adapter DEMO.SIMPLE_MESSENGER
23-Feb-12 16:59:32,953|INFO |LightstreamerMonitorText         |Timer-0                    |Total threads = 22, Total heap = 64880640 (free = 55602976), Sessions = 0 (max = 0), New sessions = [+0, -0], Connections = 0 (max = 0), New connections = [+0, -0], In-pool threads = 10, Active threads = 0, Available threads = 10, Queued tasks = 0, Pool queue wait = 0, NIO write queue = 0, NIO write queue wait = 0, NIO active write selectors = 0, NIO total selectors = 0, Subscribed items = 0, Inbound throughput = 0 updates/s, (pre-filtered = 0), Outbound throughput = 0 updates/s, (0kbit/s, max = 0), Lost updates = 0 (total = 0), Total bytes sent = 0, Extra sleep = 0, Notify delay = 0

before that it worked

thanks again

awadkab

Hello, :Smile_Ab:

I found the problem.
I was copy LS_chat_data_adapter.jar and LS_chat_metadata_adapter.jar then post it to my java folder (C:\Program Files\Java\jre6\lib\ext)

because that I had that problem and when I delete it from there the server work now.

I wish see tutorial like step by step to let me start use this great project

thanks