The value of the local variable is not used
<p>all of the variables above have the warning in the title. Could you please tell me why that is happening?</p>

<pre><code>public class DataTypes {
    public static void main(String[] argv) {
        // new feature in JDK 7
        int x = 0b1010; // 12
        int y = 0b1010_1010;
        int ssn = 444_12_7691;
        long phone = 408_777_6666L;
        double num = 9_632_401_909.1_0_3;
        String twoLine = "line one\nline two";
    }
}
</code></pre>