"N/A" is not an integer so check before parsing or handling Exceptions properly.
Exception Handling.
try{
int i = Integer.parseInt(input);
} catch(NumberFormatException ex){ // handle your exception
...
}
Integer pattern matching.
String input=...;
String pattern ="-?\\d+";
if(input.matches("-?\\d+")){ // any positive or negetive integer or not!
...
}
These are the two options you can try. It has worked for me and hope it works for you as well.