/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		Scanner sc = new Scanner(System.in);
 
		System.out.println("Type a double-type number:");
		while (!sc.hasNextDouble())
		{
		    System.out.println("Invalid input\n Type the double-type number:");
		    sc.next();
		}
		double userInput = sc.nextDouble();    // need to check the data type?
		System.out.println("Here it is: " + userInput);
	}
}

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

dGVzdCB0ZXN0CmludDsKCgoyMy40CjQ0LjY=

test test
int;


23.4
44.6