Introduction :
In Java, we can convert a double value to string using String.valueOf() inbuilt function. It will give the same desired output, i.e. we will get the same string value as the input. But, sometimes it may return a string with an exponential component or in scientific notation. Let me show you with an example below :
public class Main {
public static void main(String[] args) {
double number1 = 12;
double number2 = 0.054;
double number3 = 0.000047823458;
System.out.println(String.valueOf(number1));
System.out.println(String.valueOf(number2));
System.out.println(String.valueOf(number3));
}
}Output :
12.0
0.054
4.7823458E-5
There are multiple ways to do the double-string conversion. Let me show you one by one :
Using String.format() :
We can format a double number using String.format() method. It takes two arguments, first one is the format string and the second one is the one or more objects that need to format.
public class Main {
public static void main(String[] args) {
double number = 12.000047823458;
System.out.println(String.format("%f",number));
System.out.println(String.format("%.0f",number));
System.out.println(String.format("%.12f",number));
}
}In this example, we have used three different ways to format the same double value. It will print the below output :
12.000048
12
12.000047823458
Using Double.toString() :
Double class comes with an inbuilt method toString() method to convert a double value to string. It will not add any exponential component to the conversion.
public class Main {
public static void main(String[] args) {
double number = 12.000047823458;
System.out.println(Double.toString(number));
}
}Output :
12.000047823458
Adding an empty string :
This is the simplest way to convert a double to a string. Just add one empty string and it will convert to a string. Like below :
public class Main {
public static void main(String[] args) {
double number = 12.000047823458;
String numberInString = number + "";
System.out.println(numberInString);
}
}The output will be the same.
Using DecimalFormat :
DecimalFormat takes one pattern and based on that pattern it formats the input number and returns the string representation of the formatted number. For example :
import java.text.DecimalFormat;
public class Main {
public static void main(String[] args) {
double number = 12.000047823458;
String pattern = "##.############";
DecimalFormat decimalFormat = new DecimalFormat(pattern);
System.out.println(decimalFormat.format(number));
}
}
import java.text.DecimalFormat;
public class Main {
public static void main(String[] args) {
double number = 12.164547823458;
String pattern = "##.##";
DecimalFormat decimalFormat = new DecimalFormat(pattern);
System.out.println(decimalFormat.format(number));
}
}It will print 12.16 as the output.
Conclusion :
We have seen different ways to convert a double value to String without an exponential part. You can use any of the above methods that fit your requirement. Try to run these examples and let me know if you have any queries or if anything is missed.
