Java Scanner - hasNextDouble() Method
The java.util.Scanner.hasNextDouble() method returns true if the next token in the scanner's input can be interpreted as a double value using the nextDouble() method. The scanner does not advance past any input.
Syntax
public boolean hasNextDouble()
Parameters
No parameter is required.
Return Value
Returns true if and only if the scanner's next token is a valid double value.
Exception
Throws IllegalStateException, if the scanner is closed.
Example:
In the example below, the java.util.Scanner.hasNextDouble() method is used to check whether the scanner's next token is a valid double value or not.
import java.util.*;
public class MyClass {
public static void main(String[] args) {
//String to scan
String MyString = "Hello World 10 + 20 = 30.0";
//creating a Scanner
Scanner MyScan = new Scanner(MyString);
while(MyScan.hasNext()) {
//check if the next token is a double
//if yes, prints double value
if(MyScan.hasNextDouble())
System.out.println("Double value is: "+ MyScan.nextDouble());
//if the next token is not a double
else
System.out.println("No Double Value found: "+ MyScan.next());
}
//close the scanner
MyScan.close();
}
}
The output of the above code will be:
No Double Value found: Hello No Double Value found: World Double value is: 10.0 No Double Value found: + Double value is: 20.0 No Double Value found: = Double value is: 30.0
❮ Java.util - Scanner
