How to make a JavaFX diagram NumberAxis shows only Integer value, not double

Question

I am trying to create a chart for which yAxis is intended to display the number of employees, so it should only show integers.
But I didn’t find it as easy as I already tried yAxis.setTickUnit (1) , but it will not work when the values ​​are small (etc. The maximum value is 3, it will still show 0.5.1, 5 ..., I only need a check mark, for example, 1,2,3,4 ..)
How could I achieve this?

According to @jewelsea's answer, I tried this (in javafx 2.2 jdk7)

class IntegerStringConverter extends StringConverter<Number>{

    public IntegerStringConverter() {
    }

    @Override
    public String toString(Number object) {
        if(object.intValue()!=object.doubleValue())
            return "";
        return ""+(object.intValue());
    }

    @Override
    public Number fromString(String string) {
        Number val = Double.parseDouble(string);
        return val.intValue();
    }
}  

This is an acceptable result. The double meaning has disappeared, but there is still there.

Answer 1

tickLabelFormatter .