I'm really impressed with the functionality and capability found in the GWT async RPC mechanism which defines
com.google.gwt.user.client.rpc.RemoteService
com.google.gwt.user.server.rpc.RemoveServiceServlet
Due to the extreme limitations in the GAE hosting environment, I'm needing to bridge requests from a GAE server to another non-GAE server.
Is there a way to use the same DTOs and async RPC mechanism I'm using with the browser->server when communicating server->server ?
When you write a GWT/App-Engine App you compile and load the .class files as well as the comiled Javascript to one source. A client comes along downloads your Javascript and GWT does it's magic between the client and server.
Let's assume that now you want to forward some of the RPC calls to another server. You would need to make sure that the Serialization Ids were identical. You now have a problem that will give you fits when you don't keep every thing exactly in sync.
My recommendation to tou would be to use JSON, XML or just text for the calls that you need to forward. It now becomes easy to use the URL Fetch service of GAE.
Related
I have a client software that is written in C++/C# and a database. Now I don't want the client to access the database directly, so I thought about placing an application server in the middle. This one should get a short request from the client, ask the database for new data, do some filtering (that can't be done in sql) and then return the data to the client.
My search for this kind of software brought me to Glassfish or Tomcat but my problem in understanding is, that these always want to talk http with html/jsp. Because most of my data is encrypted anyways, I don't need such plain text protocols and would be totally happy with something that just takes a byte stream.
On the other hand would it be nice to have a server handle the thread pool for me (don't want to implement all that from scratch).
After more than a day of searching / testing I'm even more confused than at the beginning (ejb, beans, servlet, websocket, ... so many things to google before understanding just the simplest tutorials).
TL;DR: how do I get Tomcat/Glassfish to just open a socket and create a new thread for every request, without any HTML/CSS/JSP involved?
Jetty and Tomcat are so called servlet container and thus primarly targeted at HTTP exchanges. Glassfish is an application server that uses a servlet container as one of its modules. I would stop thinking in that direction - that's all more like web applications and web services - some levels too high what you are asking for.
I think you should more look into sth. like Netty which is merley a "high performance protocol" server. Take a look at the documentation here (even some sort of tutorial there which might fit your use case).
GlassFish is an "enterprise application server", targeting the Java EJB specification. That's surely overdone for your purpose. You can give Tomcat a try. It is a "servlet container", targeting Java Servlet specification. Servlets have one purpose: listening to an incoming URL (request), executing Java code and returning a response, usually over HTTP.
For sure, you may start your own (plain) ServerSocket, for example using a ServletContextListener (which will be started once your application starts). But you should go for a higher protocol to send the data, like Hessian and Burlap, which is implemented in both, Java and C++ and easy to set up.
Anyone has expirience on having Jruby project running on Jboss (using torquebox or whatever) with an ability to communicate with another "japps" not on the same jboss where jruby app is, i.e. some java project on another jboss?
I know there is an torque-messanging but dunno if it's possible to communicate with external(out of jruby-app's jboss) app?
Best practices are welcomed.
Thanks in advance.
P.S. placing that other app on the jboss where jruby app is not acceptible solution.
I can recommend you to use Thrift and build communication via them.
Thrift have generator for both your needed languages (Java and JRuby) and provide good and fast communication.
UPDATED:
Thrift is RPC (remote procedure call) framework developed at Facebook. In detail you can read about it in Wiki.
In few word to save you time, what it is and how to use it:
You describe you data structures and service interface in .thrift file(files). And generate from this file all needed source files(with all need serialization) for one or few languages(what you need). Than you can simple create server and client in few lines
Using it inside client will be looks like you just use simple class.
With Thrift you can use what protocol and transport used.
In most cases uses Binary or Compact protocol via Blocked or Not-blocked transport. So network communication will be light and fast + with fast serialization.
SOAP(based on XML on HTTP) packages, its in few times bigger, and inappropriate for sending binary data, but not only this. Also XML-serialization is very slow. So with SOAP you receive big overhead. Also with soap you need to write (or use third-party) lib for calling server(tiny network layer), thrift already made it for you.
SMTP and basically JMS is inappropriate for realtime and question-answer communication.
I mean if you need just to put some message in queue and someone sometime give this message and process it — you can (and should) use JMS or any other MQ services(Thrift can do this to, but MQ architecture is better for this issue).
But if you need realtime query-answer calls, you should use RPC, as protocol it can be HTTP(REST, SOAP), binary(Thrift, ProtoBuf, JDBC, etc) or any other.
Thrift (and ProtoBuf) provide framework for generate client and server, so it incapsulate you from low level issues.
P.S:
I made some example in past https://github.com/imysak/using-thrift (communication via Thrift Java server + Java Client or node.js client), maybe it will be useful for someone . But you can found more simple and better examples.
Torquebox supports JMS. The gem you specified torquebox-messaging allows for publishing and processing of HornetQ messages on the local JBoss AS server/cluster that the JRuby app is running in. I don't think it currently supports connecting to remote servers.
Using this functionality in your JRuby app you could then configure your Java app on another server to communicate with HornetQ running in the JBoss AS that the JRuby app is running on.
Alternatively you could always implement your own communication protocol or use another Java library - you have access to anything Java you want to run from JRuby.
You can use Web Services or JMS for that
I have to implement a webservice which will be used by different clients written using several languages (e.g. Java,C#) and frameworks.
Because of this i decided to use JAX-WS and the Apache CXF Framework to create an WSDL first webservice.
Now my problem is that the webservice has to notify all clients whenever the user performed certain actions on one of them (like adding an element to the database).
After some research I found that the technique of long-polling might help me to get this task done. However I'm not sure that this is the best solution and that this one will work on all target plattforms.
Is the technique of long-polling suited in a Webservice (WSDL) context or is there another method widely used and supported?
Long polling or Comet techniques are best used for this scenario, Web services are stateless and don't support pushing data to clients without heavy modification of the hosting service, i.e. IIS, Apache... etc.
I'm looking for some advice on the simplest way to create some product registration communication. I have a Java desktop application that needs to be re-newed every year. When a user downloads and install this app (through JNLP) they get a limited demo-version. There is code in place on the client to "register" the product and unlock all of the features.
My next step is to build the server-side components. There will be a database with customer ID numbers and other information about the customer. When the user clicks register, some contact information will be sent to the server as well as some product registration ID. The server will check this against the database and then either give the client the o.k. to unlock the features or the user will be informed that the registration id was not valid. This seems like a very standard thing. So what is the standard way to do it?
I have my own VPS and I'm running Tomcat, so I'm really free to implement this any way I choose. I was planning on building some web service, but I have never used REST before.
Use REST; REST is nothing more than using plain HTTP 'better'. Since you are already using HTTP, somehow you are already doing REST like calls and moving these calls to full fledged REST will be easy.
Implementing REST calls is easy. You have two approaches:
Low end: using URLConnection objects on the client, servlets on the server and following some REST conventions on using HTTP methods and 'clean' URLs (see here). Advantage is that you need no 3rd party library and minimize the footprint. Maintenance and evolutions are harder though.
High-end: a framework and specifications like JAX-RS. Using Restlet you can be up in running with a REST server in a couple of hours without having to deploy a servlet container.
Don't use SOAP. The only reason you would want to use SOAP is that you want to contractualise using a WSDL what you are exposing (you can do the same with REST btw, see the Amazon documentation for instance). Trust me, SOAP is way too heavy and confusing for what you are trying to do.
I need to push events to web clients in a cross-browser manner (iPhone, iPad, Android, IE/FF/Chrome/etc.) from a Spring based Java server. I am using backbone.js on the client side.
To my best knowledge, I can either go with a Web socket only approach, or I can use something like socket.io.
What is the best practice for this issue, and which platform/frameworks should I use?
Thanks
Looks like you're interested in an AJAX Push engine. ICEPush (same group that makes ICEFaces) provides these capabilities, and works with a variety of server- and client-side frameworks. There is also APE.
You can have a look at Lightstreamer.
My company is currently using it to push real time financial data from a web server.
I suppose Grizzly or Netty may fit your needs. Don't have a real experience in that scope, unfortunately.
I'd recommend socket.io as you mentioned in your question, if you're doing browser based eventing from a remote host. Socket.io handles all the connection keep-alives and reconnections directly from javascript and has facilities for channeling messages to specific sessions (users). The real advantage comes from the two-way communication of WebSockets without all the boilerplate code of maintaining the connection.
You will need to do some digging for a java implementation thoughConsider running the server directly from V8.