Java，奇怪的比较结果

import java.util.Scanner;
import java.io.PrintStream;
import java.util.Random;

public class Main {

    public static PrintStream out = System.out;

    public static Scanner in = new Scanner(System.in);

    public static void main(String[] args) {
        float a = 0, b = 0;
        boolean d, l;
        if (in.hasNextInt())
            b = in.nextInt();
        d = (-3.0 <= b) && (b <= 5.0);
        l = (9.0 <= b) && (b <= 15.0);
        out.print(d || l);
    }

}

6.2 的结果 - d = true(??), l = false

为什么？（