Cell cellC1 = _sheet1.setCellEditText(0, 2, "=bankAccount3"); //C1
Cell cellD1 = _sheet1.setCellEditText(0, 3, "=SUM(A1:C1)"); //D1
Cell cellE1 = _sheet1.setCellEditText(0, 4, "=bankAccount1 + bankAccount2 + bankAccount3"); //E1
Map varmap = new HashMap();
VariableResolver resolver = new SimpleResolver(varmap);
_book.addVariableResolver(resolver);
varmap.put("bankAccount1", new Double(1d));
varmap.put("bankAccount2", new Double(10d));
varmap.put("bankAccount3", new Double(100d));