Programming Wireless Devices with the Java2 Platform

Chapter 4. Connected Limited Device Configuration

This chapter introduces the Connected, Limited Device Configuration (CLDC), one of the core building blocks of the Java™ 2 Platform, Micro Edition (J2ME™). The goal of the Connected, Limited Device Configuration is to provide a standardized, highly portable, minimum-footprint Java application development platform for resource-constrained, connected devices. The CLDC target devices are characterized generally as follows:

• at least 192 kilobytes of total memory budget available for the Java platform,

• a 16-bit or 32-bit processor,

• low power consumption, often operating with battery power, and

• connectivity to some kind of network, often with a wireless, intermittent connection and with limited (often 9600 bps or less) bandwidth.

CLDC is core technology that can be used as the basis for one or more J2ME profiles. Cell phones, two-way pagers, personal digital assistants (PDAs), organizers, home appliances, low-end TV set-top boxes, and point-of-sale terminals are some, but not all, of the devices that might be supported by the Connected, Limited Device Configuration.

The material in this chapter comes from the CLDC Specification document that is available from the Java Community Process (JCP) web site.^[1] The CLDC Specification defines the minimum required complement of Java technology components and libraries for small connected devices. Java language and virtual machine features, core libraries, input/output, networking, and security are the primary topics addressed by the CLDC Specification.

^[1] http://jcp.org/en/jsr/detail?id=139