Posts tagged servlet
Session at JavaOne come in various shapes. Some are visionary, high level and future oriented. Others are detailed and discuss practical, sometimes very fine grained topics. One of the sessions I attended was somewhere in between: future oriented yet pretty concrete at the same time. It was probably my favorite session at JavaOne this year: What’s new in Servlet3.1: An Overview by Shing Wai Cha and Rajiv Mordani. The passion of the presenters – their enthusiasm to explain the current development of the Servlet API and their ability to demonstrate some rather tough concepts were pivotal. Many presenters can take their style as an example they can learn from.
The Servlet 3.1 API is part of the JEE 7 edition- that is scheduled for complete release in April 2013. The Servlet Specification is largely complete, although some elements are still under discussion as became clear during this talk. The probably most important new requirement in Servlet 3.1 is the ability to do Web Socket interaction. Web Sockets is a relatively new communication protocol that runs over TCP/IP and goes beyond HTTP in several respects. Web Sockets support bi-directional interactions (open channels through More >
Push based synchronized Slideshow demo application implemented using CometD and jQuery running on Tomcat2
In a string of recent articles, I have discussed downloading, installing and running demos for a number of different tools, frameworks and libraries that support push-style (web) applications in one way or another. I have looked into â€˜classicâ€™ comet with Grizzly, Atmosphere and CometD as well as ADF Active Data Service and WebLogic Pub/Sub (Bayeux) Channels. I have also looked to WebSockets with jWebSocket, again Atmosphere and CometD and also with Kaazing. I am now working on a series of articles in which I use each of these frameworks and push infrastructures to implement the same simple push-style application – to see how that goes and to compare the various implementations. The functionality I will be implementing is simple:
- the selection of the image is communicated to the server (background WebSocket based or alternatively regular AJAX)Comet (Bayeux)/Long Poll style)
- the server informs all connected clients about the selected image through a pushed message (background WebSocket based or alternatively Comet (Bayeux)/Long Poll style); these clients all synchronize that slide More >
Tomcat 7 is a Servlet Container – a fairly light weight container, very convenient for development and testing. While not a full application server, Tomcat implements the functionality described in the Java Enterprise Edition Web profile specifications. Most notably, it supports version 3.0 of the Servlet API (application programming interface) and version 2.2 of JavaServer Pages, both part of the recently ratified JEE 6.
Installing Tomcat 7 is dead-easy and configuring Tomcat as Server in NetBeans to allow direct (re)deployment of web applications from within NetBeans is just as easy. Still, a brief blog article explaining the steps – for even easier lives for Java Web developers. And as testimonial to the ease of use the development teams behind Tomcat and NetBeans provide to the world of Java developers.
In one of my previous posts I showed how to use ADF popup components to display external content such as webpages like wikipedia in an inline frame. Based on this post a colleague of mine tried to display a PDF document. That didn’t work. In this post I explain how you can use a servlet to open a PDF document in the inline frame. I will not explain how to invoke popups. If you need to know how to do that, refer to the post mentioned earlier (more…)