code: private boolean updateExceptionRegister(CatchInfo ci, int seen, int pc) {
          if (OpcodeUtils.isAStore(seen)) {
              int reg = RegisterUtils.getAStoreReg(this, seen);
              ci.setReg(reg);
              exReg.put(Integer.valueOf(reg), Boolean.TRUE);
              LocalVariableTable lvt = getMethod().getLocalVariableTable();
              if (lvt != null) {
                  LocalVariable lv = lvt.getLocalVariable(reg, pc + 2);
                  if (lv != null) {
                      int finish = lv.getStartPC() + lv.getLength();
                      if (finish < ci.getFinish()) {
                          ci.setFinish(finish);
                      }
                  } else {
                      return false;
                  }
              }
          }
          return true;
      }
docs: looks to update the catchinfo block with the register used for the exception variable. If their is a local variable table, but the local variable can't
  be found return false, signifying an empty catch block.
  
  @param ci
  the catchinfo record for the catch starting at this pc
  @param seen
  the opcode of the currently visited instruction
  @param pc
  the current pc
  
  @return whether the catch block is empty