A recipe for cookie management
Client-side HTTP state management is important for creating
Java applications that need to interact with Web applications
like browser-based email or online banking services. This
article presents a cookie library for robust and easy
client-side HTTP state management in Java, a library sorely
missing in the native java.net toolkit. Though there exist
several client-side HTTP state management APIs, they prove
difficult to learn and unnecessarily reinvent the wheel. The
cookie management library that Sonal Bansal outlines in this
article is thin and robust, and uses the core Java API objects
as much as possible.
Networking with J2ME
If you've been following Soma Ghosh's articles here on the Wireless zone, you've learned how to use your Java skills to build simple applications for handheld devices. Now how do you link those devices to the outside world? In this article, Ghosh discusses the javax.microedition.io and java.io classes that lie at the heart of J2ME networking. You'll learn how J2ME applications handle URLs and accept input, and even be taken through a sample program that downloads currency exchange information to any network-accessible, J2ME-compatible device.
Networking, User Experience, and Threads
This article describes several approaches to providing user feedback during network activity, and to managing threads appropriately. It starts with a simple MIDlet that provides no feedback, then gradually enhance it.
Session Handling in MIDP
A typical multitier application stores its data, including user
information or preferences, in a database. Client devices send
requests to a Web tier, which processes them and sends
responses back. The Web tier retrieves user information from
the database to customize its behavior for a particular user.
Applications use a technique called session handling to avoid
looking up user information each time the client communicates
with the server. This article describes session handling,
starting at the server side and continuing through to the
client. It includes servlet and MIDlet code examples.
The Generic Connection Framework
Today you can find the GCF not only in CLDC-based profiles,
such as the Mobile Information Device Profile (MIDP) and the
Information Module Profile (IMP), but also in Connected Device
Configuration (CDC)-based profiles, such as the Foundation
Profile and its relatives the Personal Basis Profile and
Personal Profile - and now, with JSR 197, on the J2SE platform
as well. You can also find the GCF in an increasing number of
optional packages, including those that provide Bluetooth
support and access to files and smart cards.
Track wireless sessions with J2ME/MIDP
Every e-commerce application must support session tracking.
Unfortunately, MIDP (Mobile Information Device Profile), a J2ME
(Java 2 Platform, Micro Edition) technology, supports only the
standard HTTP protocol, which is stateless. In this article,
Michael Juntao Yuan and Ju Long explore ways to add session
support into the current MIDP network API framework. They
discuss the implementations, usages, and relative merits of
three approaches: using cookies, rewriting URLs, and embedding
session information in XML documents.
Using HTTPS with MIDP
Any information transmitted over wireless links is subject to interception. Some of that information could be sensitive, such as credit card numbers and other personal data. To make handheld wireless devices more useful in an enterprise setting and for m-commerce, applications must protect their users' information, using encryption, authentication, and secure communications protocols.
Wireless Application Programming with J2ME and Bluetooth
Imagine being able to use your Bluetooth-enabled mobile phone to lock and unlock your car, operate your garage door, and control your TV, VCR, DVD player, and other consumer appliances. If you want to make that kind of control available to your users, you'll need to be able to write Bluetooth applications that customize these appliances, and deploy them in a way that lets users download them, to a cell phone for example. Bluetooth and J2ME can work together to achieve this unified vision. Bluetooth allows devices to communicate wirelessly and J2ME allows you to write custom applications and deploy them on mobile devices.
Advanced Imaging provides the latest information on the imaging hardware, software and peripherals that are used in capturing, displaying, manipulating and storing images.
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