Convert a string to a number in Java

To convert a string to a number in Java, use the Integer.parseInt() method. First, let's create a string and set its value.

String str = "45";

Now, get an Integer and use the Integer.parseInt() method.

Integer i = Integer.parseInt(str);

Let's see the complete example.

Example

public class Demo {
　　　public static void main(String args[]) {
　　　　　　String str = "45";
　　　　　　Integer i = Integer.parseInt(str);
　　　　　　System.out.println("Num: "　+　i);
　　　}
}

Output Result

Num:　45