Mobile Service Architecture - JSR 118

JSR 118 - Mobile Information Device Profile 2.1

MIDP provides the core functionality for mobile applications, including user interface, network connectivity, local data storage, and application lifecycle management. It is targeted at mobile devices such as wireless handsets or PDAs. More information may be found at java.sun.com/products/midp.

Packages

java.lang
java.util
javax.microedition.io
javax.microedition.lcdui
javax.microedition.lcdui.game
javax.microedition.media
javax.microedition.media.control
javax.microedition.midlet
javax.microedition.pki
javax.microedition.rms

System Properties

Articles

javax.microedition.io

• A Generic Connection Framework cheat sheet - The Generic Connection Framework (GCF) is based in CLDC but can be found in many profiles and optional packages. Presented here, a summary of the many schemes based on the GCF with interface hierarchy, BNF and examples.
  
  
• J2ME Low-Level Network Programming with MIDP 2.0 - Provides an overview of the MIDP 2.0 CLDC Generic Connection Framework, and examines the new support for sockets and datagrams.
  
  
• HTTP POST Basics - A presentation of the benefits and usage model of the HTTP POST method. The POST method is explained and compared to the HTTP GET method. Code samples illustrate the usage of each method in the MIDP environment.
  
  
• MIDP Terminal Emulation, Part 1: A Simple Emulator MIDlet - This article explores the socket support in the Generic Connection Framework (GCF) by building a small and simple terminal emulator that implements the telnet protocol.
  
  
• MIDP Terminal Emulation, Part 2: Advanced Terminal Emulation - This article expands the simple terminal in Part 1 to include user input and Telnet connectivity to remote servers.
  
  
• MIDP Terminal Emulation, Part 3: Custom Fonts for MIDP - Third in the terminal emulation series where we add some polish and some badly needed control over the terminal emulator's appearance by taking advantage of MIDP's capabilities for rendering custom fonts.
  
  
• MIDP Terminal Emulation, Part 4: Securing Your Mobile Communications - In the 4th and final part of "MIDP Terminal Emulation", Michael Powers extends the telnet client to operate over a secure socket connection.
  
  
• The MIDP 2.0 Push Registry - Introduces the MIDP 2.0 push registry which manages network and timer initiated MIDlet activation.

javax.microedition.lcdui

• Writing a Custom Counter Component - MIDP 2.0 introduced the javax.microedition.lcdui.CustomItem class. As the name implies, a developer can now create custom UI components by extending the CustomItem class. This tech tip designs and implements a UI component for displaying a numeric counter and of course, source code is available.
  
  
• Alerts in MIDP 2.0 - Don't leave the user guessing, provide visual feedback of MIDlet progress using MIDP 2.0 alerts. New alert features provide an interface to associate a javax.microedition.lcdui.Gauge item with a javax.microedition.lcdui.Alert. By adding a javax.microedition.lcdui.CommandListener interface alerts can also provide users more control over MIDlet processing. Sample source code is available for download.
  
  
• Custom Item Traversal in MIDP 2.0 - Navigating between and within UI components is a common user activity. Learn about the MIDP 2.0 javax.microedition.lcdui.CustomItem traversal model to enhance your custom UI components.
  
  
• Interaction Modes in MIDP 2.0 - MIDP 2.0 introduces three user interaction modes in the javax.micoredition.lcdui package. Custom UI items can discover the interaction modes available in an implementation at run-time. Learn how to identify and dynamically adapt to interaction modes in your javax.microedition.lcdui.CustomItem components.
  
  
• Using Custom Items in MIDP 2.0 - This tech tip shows how to use the MIDP 2.0 CustomItem widget to develop new custom form elements.
  
  
• MIDP Event Handling 1.0 release - Learn how to handle high-level and low-level MIDP events with easy-to-understand examples.
  
  
• Customizing Forms With CustomItems - This article demonstrates the new MIDP 2.0 custom capabilities by building a simple outliner MIDlet.

javax.microedition.lcdui.game

• Game Canvas Basics - Introduces the MIDP 2.0 GameCanvas class and the game loop concept. Required reading for all aspiring "first person shooter" developers.
  
  
• Getting Started With the MIDP 2.0 Game API - Get game with the MIDP 2.0 (JSR 118) javax.microedition.lcdui.game API. Discover the features of the game API, covering: Screens and Canvases, Layers, Sprites and Tiles along with animation techniques.
  
  
• Creating 2D Action Games with the Game API - One of MIDP 2.0's new features is a Game API which simplifies the task of writing 2D games. This article describes the two components of the Game API, a layer-based animation framework and a new Canvas subclass that is useful for game loops.
  
  
• Mobile Multiplayer Gaming, Part 1: Real-Time Constraints - Michael Powers explores the mobile game space. Where are the games? What are the design constraints? What does it takes to be successful? Read Part 1 and be ready for the next installment in the series.
  
  
• Mobile Multiplayer Gaming, Part 2: Applied Theory - continues Michael Powers' game development series. This installment builds a prototype multi-player, networked game. Read this installment and use the source download as the foundation for your own game project.
  
  
• Mobile Multiplayer Gaming, Part 3: Multiplayer Gaming with Bluetooth - In the final part of his Mobile Gaming series Michael Powers shows the ease with which Bluetooth can be added to the game to enable local-area wireless play. Download the sample source, read part 3 and apply the modifications for Bluetooth game play.

javax.microedition.midlet

• MIDP Application Properties - Increase the flexibility of your MIDlets by saving configuration settings as application properties. Save development and test time by keeping settings in one convenient location.
  
  
• Invoking Platform Services in MIDP 2.0 - Learn how to use the MIDP 2.0 javax.microedition.midlet.MIDlet.platformRequest method to access features outside of the J2ME run-time environment. The J2ME Wireless Toolkit supports the platformRequest method and can be configured to invoke a user-specified service.
  
  
• Retrieving MIDlet Attributes - This tech tip describes how to use attributes with a MIDlet suite to add flexibility and reduce test time by separating configuration data from the Java source code. The tech tip also discusses using attributes in both trusted and untrusted MIDlet suites.
  
  
• Learning Path: MIDlet Life Cycle - By focusing on extensive source code examples, this learning path shows the basic life cycle control elements needed when implementing your application's build, source base, and delivery strategies.
  
  
• Managing the MIDlet Life-Cycle with a Finite State Machine - This articles shows a simple and effective means to control a MIDlet's life-cycle and overall application behavior using a Finite State Machine.

javax.microedition.rms

• Sharing Data Between MIDlet Suites - A discussion of MIDlet data sharing using the MIDP 2.0 RMS package. How to share data, access control and security topics are presented in the context of a working example. Source code is available, ready to use with the J2ME Wireless Toolkit.
  
  
• Databases and MIDP, Part 1: Understanding the Record Management System - This article is the first in a series that will explore RMS and the larger issues surrounding its use in MIDP applications, such as interacting with external data sources like relational databases. We'll start by exploring what RMS has to offer and writing some simple RMS debugging aids.
  
  
• Databases and MIDP, Part 2: Data Mapping - This article describes data mapping strategies you can use to encapsulate low-level storage operations so your applications can store and retrieve persistent data efficiently and effectively.
  
  
• Databases and MIDP, Part 3: Putting Data Mapping to Work - In this article you'll learn how to distance your applications from these lower-level operations, by extending core classes to include reading and writing operations, and by creating field lists and using them to store and retrieve objects.
  
  
• Databases and MIDP, Part 4: Filtering and Traversal Strategies - This article explores the different strategies for finding the data you need, and to navigate the record store, sort records into a useful order, and use filters to extract wanted records.
  
  
• Databases and MIDP, Part 5: Searching a Record Store - This article explores the various strategies for finding one or more records that meet criteria you specify.