This second part of Michael Cymerman's MIDP series will focus on the development of an application using non-graphical user interface components. In addition, he'll explore the conversion and storage of application data to the MIDlet RecordStore. These two concepts are discussed in detail through a simple Stock Portfolio management application constructed specifically for this demonstration. (4,700 words)
The Palm platform is built on the proposition that a strong developer community and good tools enable the creation of interesting applications and a broad user base. This article shows you how to leverage the strengths of the PalmOS and its development environment to build consumer-device applications in Java. (4,100 words)
3. Build database-powered mobile applications on the Java platform
In this article, Michael J. Yuan and Ju Long explain how to create mobile database applications using the Java 2 Platform, Micro Edition/Mobile Information Device Profile (J2ME/MIDP) and the Java 2 Platform, Enterprise Edition (J2EE). The authors introduce an architecture that uses JavaServer Pages (JSPs) as middleware between a MIDP frontend and a database backend. They also explain specific design decisions and implementation issues, such as persistent storage, network connection, session management, and data communication. Their discussion focuses on the integration between the client and server-side Java applications. (3,100 words; January 18, 2002)
Without too much platform customization or rework, vendors can use MIDP-compliant devices to develop applications that can run on multiple wireless platforms. This article, the first in a three-part series, introduces you to the concept of MIDP APIs and the J2ME platform. You will be exposed to the APIs used to generate graphical, form-based, storage-driven code that is capable of connecting with external resources. (3,500 words)
In the final part of this MIDP series, Michael explores the methods of communication between the MIDlet and the world at large. Using the APIs contained in Java 2, Micro Edition's Mobile Information Device Profile (MIDP), developers can interact with external systems. This article will explore these APIs in a detailed example, which demonstrates the interaction that can exist between a J2ME device and a servlet-based Web system. (3,000 words)
Portlets are Java-based Web components, managed by a portlet container, that process requests and generate dynamic content. Portals use portlets as pluggable user interface components that provide a presentation layer to information systems. The next step, after servlets in Web application programming, portlets enable modular and user-centric Web applications. The goal of JSR (Java Specification Request) 168, the Portlet Specification, is to enable interoperability between portlets and portals. This specification defines the contract between portlet and portlet container, and a set of portlet APIs that address personalization, presentation, and security. The specification also defines how to package portlets in portlet applications. Part 1 of this two-part series describes the Portlet Specification and explains its underlying concepts. In Part 2, the authors explain the specification's reference implementation and show some portlet examples. (3,300 words; August 1, 2003)
While the public release of a common API for portlets is still a couple of months away, Java developers can use proprietary APIs from corporate portal vendors to experiment with portlet development. In this article, Carl Vieregger introduces SAP's portlet API and provides a detailed example that renders information from a remote database using single sign-on. He also demonstrates how you can run the example portlet within your own development and deployment environment based on SAP's Portal Development Kit. (3,300 words; February 7, 2003)
In the final part of this MIDP series, Michael explores the methods of communication between the MIDlet and the world at large. Using the APIs contained in Java 2, Micro Edition's Mobile Information Device Profile (MIDP), developers can interact with external systems. This article will explore these APIs in a detailed example, which demonstrates the interaction that can exist between a J2ME device and a servlet-based Web system. (3,000 words) By Michael Cymerman
