Java Virtual Machine (Java Series)

iinc

iinc <varnum> <n> or wide iinc <varnum> <n> In the first form, <varnum> is an unsigned integer in the range 0 to 0xFF and <n> is a signed integer in the range -128 to 127. In the second (wide) form, <varnum> is an unsigned integer in the range 0 to 0xFFFF and <n> is a signed integer in the range -32768 to <= 32767.

Stack

iinc increments the int held in the local variable <varnum> by <n>. The iinc instruction takes two parameters: <varnum> is an unsigned integer which indicates which local variable should be used. <n> is the integer amount to increment or decrement the variable by. <varnum> must be a valid local variable number in the current method's frame.

Example

iinc 1 10 ; increment local variable 1 by 10. iinc 1 -1 ; decrement local variable 1 by 1. Bytecode

For local variable numbers in the range 0-255, and values of <n> in the range -128 to 127, use:

wide

Java Virtual Machine, by Jon Meyer and Troy Downing, O'Reilly Associates