Check out example codes for "how to parse a string into a number in java". It will help you in understanding the concepts better.

Code Example 1

String toBeParsed = "15";
int parsedString = Integer.parseInt(String.valueOf(toBeParsed));
/*this makes the integer value of parsedString the number held
in the string toBeParsed*/
/*Side note: you will have to import java.lang.String to be
able to use Integer.parseInt() and String.valeOf() */

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