How to Convert Java double to String

In Java, we can convert double into a String in the following two ways:

• by using String.valueOf() method

• by using Double.toString() method

1. By using String.valueOf() Method

The valueOf() method is a part of String class. It is a static method that converts a double into a String value.

Example 1:

Here the double value passed in the method is converted into a String.

public class StudyTonight
{  
	public static void main(String args[])
	{  
		double n = 500.88;  
		String s=String.valueOf(n); 
		System.out.println("The string value is " +s);
		System.out.println(n+100); //will return 600.88 because + is binary plus operator 
		System.out.println(s+100);//will return 500.88100 because + is string concatenation operator  
	}
}

The string value is 500.88
600.88
500.88100

2. By using Double.toString() method

The toString() method is a part of Double Class. It is a static method that can also be used to convert double value to String.

Example 2:

Here the double value passed in the method is converted into a String.

public class StudyTonight
{  
	public static void main(String args[])
	{  
		double n = 500.77;  
		String s = Double.toString(n); 
		System.out.println("The string value is " +s);
		System.out.println(n+100); //will return 600 because + is binary plus operator 
		System.out.println(s+100);//will return 500100 because + is string concatenation operator  
	}
}

The string value is 500.77
600.77
500.77100

Example 3:

Here the double value passed in the method is converted into a String formatted up to a specified number of digits.

import java.text.DecimalFormat;
public class StudyTonight
{  
	public static void main(String args[])
	{  
		double num = 500.88;  
		System.out.println(String.format ("%f", num));
		System.out.println(String.format ("%.9f", num));
		DecimalFormat decimalFormat = new DecimalFormat("#,##0.000000");
		String numberAsString = decimalFormat.format(num);
		System.out.println(numberAsString);
	}
}

500.880000
500.880000000
500.880000

Example 4:

Here the double value passed in the method is converted into a String using concatenation.

public class StudyTonight
{  
	public static void main(String args[])
	{  
		double num = 500.88;  
		String s = num+""; //concat
		System.out.println(s);
	}
}

500.88