There is multiple way to Convert String to Number in java.
Integer valueOf() Method :-
The java.lang.Integer.valueOf(int a) is an inbuilt method which is used to return an Integer object.
Now intValue() method convert Integer object to primitive type int.
Syntax:- public static Integer valueOf(int a)
Using Built in Functions:-
Here we are using Integer.parseInt() method to convert String to Number.
public class StringToNumberDemo {
public static void main(String[] args) {
String str = "123";
// from Integer valueOf() Method
int d = Integer.valueOf(str).intValue();
System.out.println("from valueOf method :- " + d);
// Integer.parseInt() method
int i = Integer.parseInt(str);
System.out.println("from built in method value :- " + i);
}
}
Output :-
from valueOf method value :- 123
from built in method value :- 123