How to merge two strings into another variable

Question

The following is the situation:

I have three String parameters a1,a2,a3

Each of the parameter has a different number inside

a1: 12

a2: 34

a3: 56

So using a for -loop i want to insert these number into a method

items = the amount of parameters so in this case 3

 for (int i=1;i<=items;i++){
    popupCmplx_RPM(a+i);
    sleep(2);
    }

So the problem is if I run the functionality it will create for the String a1: a+i -> 121 instead of 12

The parameters are already set I can't change that part of the code so help is appreciated. I sure there is an easier way without the parameters, but other that adding new code I can't remove those

The total amount of parameters set at the moment are 16 some of which can be 0 so in this example there are only three and the rest are zero. with the int items variable the amount of parameters used is given

How many of these variables do you have, only ever a1 a2 and a3, or more ? (place your strings in an array or some collection, it'll be easier to iterate over them if you have a variable amount of strings) — nos, Dec 08 '11 at 13:52
I'm confused as to what it is you're asking. Do you want to iterate through passing the values of a1, a2 and a3 to the `popupCmplx_RPM()` method? If so, where are the three strings stored, and what's `items`? — Anthony Grist, Dec 08 '11 at 13:53
I'm not sure if I'm understanding your code correctly. What is "a+i" referencing to? a1,a2 and a3? — keyser, Dec 08 '11 at 13:55
You cannot do this the way you're trying to do it. If I understand you right, you have 16 variables named `a1` through `a16`. You have a collection, `items`, which indicates which of those named variables are non-zero and should be used. You're trying to loop over `items` and concatenate the index onto the string "a" to reference a variable name, and then pass that as an argument to the method. Is that what you're trying to do? — Rob Hruska, Dec 08 '11 at 14:17
that was the idea, but I know that doesn't works so I was wondering if people had any suggestions into solving this — Eve, Dec 08 '11 at 14:33

score 2 · Accepted Answer · answered Dec 08 '11 at 13:58

2

It looks like you're looping and trying to use the index of the loop to reference a variable. You cannot do that (without reflection) in Java.

^{(If that's an incorrect interpretation of your question, please update it to clarify.)}

You probably have a couple options:

Just reference the variables without looping:

popupCmplx_RPM(a1);
sleep(2);
popupCmplx_RPM(a2);
sleep(2);
popupCmplx_RPM(a3);
sleep(2);

Store the values in a collection instead of individual variables:

List<Integer> list = new ArrayList<Integer>();
list.add(12);
list.add(34);
list.add(56);

for(Integer value : list) {
    popupCmplx_RPM(value);
    sleep(2);
}

answered Dec 08 '11 at 13:58

Rob Hruska

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that would work if it where only three variables. But from the application down I get 16 variables/parameters some of which can be 0 so these i don't need( that's what the int items is for) – Eve Dec 08 '11 at 14:13
@Eve - It would be helpful to explain those sorts of things in the question. Can you update it to be more clear? – Rob Hruska Dec 08 '11 at 14:14

score 0 · Answer 2 · answered Dec 08 '11 at 13:55

0

You have to parse the String as an int, and then add one to it, like

int myInt = Integer.parseInt(a) + 1;
popupCmplx_RPM(myInt);

Careful, this can throw NumberFormatException if a isn't a valid integer.

answered Dec 08 '11 at 13:55

Ernest Friedman-Hill

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How to merge two strings into another variable

2 Answers2