Managed Smart Clients 4.1 Container-Managed Applications In the field of software engineering, the term container refers to specialized software that runs other software. For example, The MIDP Application Management Software (AMS) is a container that installs, starts, pauses, stops, updates, and deletes MIDlet applications. In the CDC Personal Basis Profile, the Xlet programming model also features container-managed life-cycle methods. A Java servlet engine is a container that invokes servlets and provides access to the HTTP context. The Java Virtual Machine (JVM) itself is a container. It monitors Java applications for proper memory usage (garbage collector) and security. In the next two sections, we will discuss the features and benefits of mobile containers. 4.1.1 Container Features As mobile enterprise applications become mainstream, the complexity of smart clients grows. For example, fully commercial applications often require features such as user login, logging, transaction, and transparent data access. Without proper tools for code and service reuse, mobile developers have to duplicate those functionalities for every smart client. Wasting time reinventing the wheel is not only inefficient but also causes error-prone code. Hence, it makes sense to make those common features available as services in software containers that run on mobile devices. An advanced…

2.1 Why Java? Before Java was called Java, it was Oak–a programming language designed for TV set-top boxes and other devices (see "Resources"). Considering its deep roots in devices, there is no surprise that many philosophies and designs behind the Java technology are perfectly suited for mobile applications. The advantages of the Java technology are as follows.   ·         Cross platform: This is very important in the diversified mobile device market. In a heterogeneous enterprise environment, the ability to develop and maintain a single client for all devices results in huge savings. ·         Robust: Since Java applications are completely managed, the bytecode is verified before execution, and memory leaks are reclaimed by garbage collectors. Even if a Java application does crash, it is contained within the virtual machine. It will not affect other sensitive applications or data on the device. ·         Secure: The Java runtime provides advanced security features through a domain-based security manager and standard security APIs. ·         Object oriented: The Java language is a well-designed, object-oriented language with vast library support. There is a vast pool of existing Java developers. ·         Wide adoption at the back end: It is relatively easy to make Java clients work with Java…

Mobile Commerce: Visions, Realities, and Opportunities 1.1 Mobile Commerce Value Propositions A lesson we learned from the bust of dot-com bubbles is that a cool technology itself does not automatically translate into business success. Successful business models leverage new technology to create values and profits from ultimate customer satisfaction. So, what new values or cost savings can mobile technology create? Unlike the PC-centric electronic commerce, mobile commerce is focused on personal experiences. A person carries a pervasive mobile device and gets information anytime, anywhere, from anyone. For the first time in history, a person's information access can be disassociated from her environment. For example, a traveler does not need to be in her office at a specific time to get ticket information. That unprecedented freedom of information could fundamentally affect all business categories. The next several sections provide a brief overview with examples. 1.1.1 Business to Consumer (B2C) From a consumer's perspective, mobile commerce provides extreme convenience, speed, and personalization to access information services. Let's use a hypothetical stock trader example to illustrate how mobile commerce can change the way we consume information. A mobile stock trader can access markets around the world anytime, anywhere. He can take advantage of…

Enterprise Concurrency The most dramatic difference between an enterprise system and a "regular" application is the number of users it must serve. As a result, enterprise applications face problems that don't often occur on the desktop. A word processor, for example, doesn't have to handle two users making changes to one paragraph at the same time—at the most, it might have to notify the second user that the document is already in use. Of course, all data-centric applications, whether they serve one user or 10,000, need to concern themselves with the validity of their data. An action that seems simple to the user ("Order a book") may require complex, choreographed activities within the application ("Check inventory, reserve stock, charge credit cards, arrange shipping, etc."). The more operations an application performs, the more likely one of those activities will fail—and when it does, the system must be able to carry on. Providing for this capability is easy in standalone applications: just don't save your changes if the mail merge fails. But if other users have been modifying the same databases at the same time, the brute-force approach to data integrity won't pan out. A lot of ink has been spilled on…