Please run:

import java.beans.*;

public class Test {

    public static class C {
        private int x;

        @BeanProperty(
            hidden    = true,
            preferred = true,
            description = "xxx"
            )
        public   void setX(int i) { x = i; }
        public double getX()      { return x; }
    }


    public static void main(String[] args) throws Exception {

        BeanInfo i = Introspector.getBeanInfo(C.class, Object.class);
        PropertyDescriptor d = i.getPropertyDescriptors()[0];

        System.out.println(d.getShortDescription());
        System.out.println(d.isHidden());
        System.out.println(d.isPreferred());
    }
}


note: here getX() returns double instead of int.

Output (JDK9 b73, linux-64): 

x
false
false
 - just default values.

If change "double getX()" to "int getX()" then the output will be as expected:

xxx
true
true