Java Program to Convert String to double

by

In the previous article we have discussed Java Program to Convert String to float

In this article we will see how to convert string type to double type.

Program to Convert String to double

Before going into the program, let’s see some examples first of both the types.

Example-1: double type

double a = 3.123456789
double b = 3.5E02
Example-2: String type 

String a = "BtechGeeks"; 
String b = "B";

Let’s see how to do it.

Explore complete java concepts from the Java programming examples and get ready to become a good programmer and crack the java software developer interview with ease.

Method 1 : Java Program to Convert String to double Using parseDouble() method

String type variable can be converted to double by using parseDouble() see how it actually works.

Here this method is a wrapper class in Java. This method of the Double class  converts the string variables into double.

Approach:

  1. Take a string value and store it in a string   variable input1.
  2. Then pass that input1 variable as parameter to parseDouble() method which will convert the string into double value and return it.
  3. Store that double value in a variable output.
  4. Display the result .

Program:

import java.util.Scanner;

public class Main
{
    public static void main(String[] args)
    {
        // creating scanner object
        Scanner sc = new Scanner(System.in);
        // input a integer value through scanner class
        System.out.print("Enter a string : ");
        String input1=sc.next();
        // converting to Double
        Double output =Double.parseDouble(input1) ;
        System.out.println("Converted Double value is : " + output);
    }

}
Output : 

Enter a String   : 6.666
Converted Double value is : 6.666

Method 2 : Java Program to Convert String to double Using valueOf() method

String type variable can be converted to double by using valueOf() , let’s see how it actually works.

This method returns an object of the Double class. However, the object will be  automatically converted into the primitive type.

 Approach:

  1. Take a string value and store it in a string variable input1.
  2. Then pass that input1 variable as parameter to valueOf() method which will convert the string into double value and return it .
  3. Store that double value  in a variable output
  4. Display the result .

Program:

import java.util.Scanner;

public class Main
{
        public static void main(String[] args)
        {
            // creating scanner object
            Scanner sc = new Scanner(System.in);
            // input a String value through scanner class
            System.out.print("Enter a string : ");
            String input1=sc.next();
            // converting to Double
            Double output =Double.valueOf(input1) ;
            System.out.println("Converted Double value is : " + output);
        }
}
Output : 

Enter a String   : 6.666
Converted Double value is : 6.666

Explore complete java concepts from the Java programming examples and get ready to become a
good programmer and crack the java software developer interview with ease.

Related Java Program: