I recently started a dynamic web application using Java/JSP and Tomcat.
I did a bit of research, and there's no specific answer about it. I have my front-end JSPs and their handling is done on the corresponding servlets. This is nice and all, and is sort of local.
But I'd want the application to also run another Java class that loops and waits for incoming UDP packets from other external clients. I have a separate UDP receive class which works fine on its own, but I'd like this code to run in the background of the web application.
Is there any way this could be done?
Thank you.
Related
I wonder if a server-side application uses Websockets for communicating
with a Web browser, can this server-side application also use
Inter Process Communication?
The idea is to use the WildFly Web server to execute an application using
Websockets. This application shall also be able to communicate with
another process. The server-side application shall thus be able to listen
both on events from the Web client and from the other process.
All applications and the other process are implemented in Java.
All help in this area is appreciated!
Thanks
Yup, this should work fine. Neither of these features should affect each other in any way.
I recently started developing my first web application with Spring and I'm stuck with a question I could not really find an answer to. What I have is a simple Spring MVC application running in tomcat which provides data in form of JSON, XML or binary via REST. This service is consumed by two clients I developed, a simple Java desktop application and an Android app. So far the clients only got information about new data by polling.
What I want now, is a way for the server to send notifications/messages to the clients when new data is available. For the Android client it would be good if the notifications could received anytime, not only when the app is currently open of course. I found lots of information for JavaScript client code but very little really useful, up-to date input about what the options for java and android clients are.
It would be really great if someone could give me some idea what would be the best way to achieve what I want (ideally something which integrates well with Spring on the server side), what protocols/libraries/frameworks to use, maybe even point me to some example or tutorial, how to implement this on server and client side.
Thanks in advance for any input.
For android or mobile devices, Google Cloud Messaging is the preferred way of sending messages to applications running on devices.
Example : spring gcm server side project and a sample tutorial.
For desktop apps, either poll regularly the server or run something in background like crontab or active-mq to check the messages and start the desktop app.
WebSockets are the best solution. check the implementation in java in the server side
I checked this thread which actually looks for the same thing that i look - but he didnt got answered.
What i'm looking for is a way to connect between server (as a java application) and a client (as a android application) - in a way that the client will be able to call remote methods in the server, and get remote objects from the server. (doesn't matter if it uses AIDL or not..)
I worked with RMI and it's fine - but it unnable to use on Android, so i have to find another way.
Thanks for help!
Two possible avenues:
Use servlets on the server and pass data via GET/POST
JAX - pass data via SOAP requests
I'm sure there are others, too.
I am developing a multi-platform (Android, iPhone, Windows and Blacbberry) mobile application. The application needs to communicate with our server for several tasks, such as retrieving buddy lists etc. The server interacts with data that is stored in a MySQL database. I intend to code the server element in Java, however I am confused by all the different types. So far, I think I have narrowed it down to three options:
1) I code the application using Jetty to accept http posts. I post XML to the server, handle it, interact with the DB and post a XML response back. I would save the application as a jar and leave it running on my server.
2)I develop a Java web service. REST/JSON/SOAP?
3)I develop a Java web application.
Whilst there are many questions already out there asking what the differences is, I am struggling to find a clear explanation as to what is the best approach in which situation. I have previously used the first approach but am assuming the second approach is the better option, I'm just not sure what the advantage is.
your 1-3 options are all variants of a "Web application".
Jetty is a Java based http server/servlet container. If you want to communicate between client and server using http, you are using an http server (although not necessarily Jetty).
A Web Service is part of a web application that conforms to a standard around how clients communicate with the server, and how the server offers up information to the clients.
A web application is a Java application that makes it services available over http.
So if you want to have your clients communicate with a server, and store info in a db, you are using a web-application.
I would recommend going with option 2 as it is more lightweight and can be parsed directly in you're web application. XML got more overhead and must be translated, while you can just serialize objects directly to JSON from you're Java application and then parse them in javascript at frontend
We are seeing Spring in school right now but we don't have the time to wait till the end of the semester to start developing an application. We continue using an app we made last year, and are writing the service layer right now.
The problem is our "client" wants to have a desktop client and a webpart, which used the same dtatabase. This would be no problem if we hook up a server that can handle RMI. So basically we want to be able to retrieve/send data to the server that runs our service layer, and use the objects on the client side as well.
I have no idea where to start digging in Spring to figure out how to do this, so some help would be appreciated.
PS: At this point I do not need MVC yet. MVC is handled from within the desktop app where we have views and controllers.The model is the same from the one on the service layer. How do we use the same model without copying it?
Check out spring remoting: http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/remoting.html
It's easy to expose your spring beans remotely, using a variety of protocols.
You might want to take a look at the REST paradigms. With this in mind you could have a web server running your server part of the application and communicating with clients through the HTTP protocol. A simple client could be a webpage in the browser which gets the corresponding HTML pages from the server, or a Swing client which communicates over JSON with the server.
The server can implement different methods for JSON or HTML communication and the server can decide what implementation to use by looking at the Accept Header of the Request objects sent to it, that's what they call Content Negotiation
JSR-311 is implemented as Project Jersey which is a framework for RESTful webservices. You might want to take a look at that.
hope that helped