Scanner: nextDouble()
/* String: string boolean: true boolean: false int: 1 int: 2 int: 3 double: 4.12 */ import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.util.Scanner; public class MainClass { public static void main(String args[]) throws IOException { int i; double d; boolean b; String str; FileWriter fout = new FileWriter("test.txt"); fout.write("string true false 1 2 3 4.12"); fout.close(); FileReader fin = new FileReader("Test.txt"); Scanner src = new Scanner(fin); while (src.hasNext()) { if (src.hasNextInt()) { i = src.nextInt(); System.out.println("int: " + i); } else if (src.hasNextDouble()) { d = src.nextDouble(); System.out.println("double: " + d); } else if (src.hasNextBoolean()) { b = src.nextBoolean(); System.out.println("boolean: " + b); } else { str = src.next(); System.out.println("String: " + str); } } fin.close(); } }