Based on Bill Verners' Inside the Java Virtual Machine, McGraw Hill Companies, 1997

tableswitch - Access jump table by index and jump
  opcode:  170 (0xaa)
  usage:
tableswitch low
   label1
   label2
   ...
   default : default_label
  stack before: ..., index
stack after: ...
 
description: If index equals low jump to label1. Else, if index equals low+1 jump to label2, etc... Otherwise jump to default_label