- J2ME: Introduction to the Platform
- Tiny VMs, Configurations, Profiles
- CLDC: A Great Starting Point
- The MID Profile
- Conclusion
- Additional Resources
CLDC: A Great Starting Point
Currently, Sun and more than 500 participating companies have worked together to define the Connected Limited Device Configuration (CLDC) as a baseline configuration for "constrained" devices (devices with limited bandwidth, memory, and user-interface capabilities). The CLDC defines the following minimum hardware requirements for a compliant device:
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160-512KB memory available for Java
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Limited poweroften battery-powered operation
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16-bit or 32-bit processor
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Network connectivity, possibly wireless, including 9600bps (or less) bandwidth
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User interface can be minimal or nonexistent
The primary difference between the Java language specification and the CLDC specification is that the CLDC doesn't provide for floating-point support. Most devices targeted by the CLDC don't provide floating-point support, and the spec writers deemed the cost to be too high to provide this support in software. CLDC libraries also don't support the Object.finalize() method. CLDC capabilities include system calls, data types, collections, input/output, calendar/time functionality, and exception/error handling from the standard java.lang, java.util, java.io libraries. The CLDC also defined a set of CLDC-specific classes. Currently, these classes are found within the new "Generic Connection Framework," which was designed to support generic connection capabilities without requiring the overhead of the standard java.net and java.io frameworks.