How can I access native methods using the Java Native Interface (JNI) from a J2ME application?

For both size and security reasons, JNI is not supported by the J2ME CLDC.

Information on the J2ME CLDC security model and additional details related to this are available in the CLDC specification, at:
java.sun.com/jcp/final/jsr030

Note: Manufacturers of J2ME-based devices can still use the native method model of their particular device, real time OS (RTOS), etc. The lack of JNI in CLDC does not affect OEM's abilities to tie their J2ME implementation into native software and services.