[FIXED] Converting empty String to null Date object with Spring

Issue

I have a form field that should be converted to a Date object, as follows:

<form:input path="date" />

But I want to get a null value when this field is empty, instead of that I receive:

Failed to convert property value of type 'java.lang.String' to required type 'java.util.Date' for property 'date';
org.springframework.core.convert.ConversionFailedException: Unable to convert value "" from type 'java.lang.String' to type 'java.util.Date';

Is there an easy way to indicate that empty Strings should be converted to null? Or should I write my own PropertyEditor?

Thanks!

Solution

Spring provides a PropertyEditor named CustomDateEditor which you can configure to convert an empty String to a null value. You typically have to register it in a @InitBinder method of your controller:

@InitBinder
public void initBinder(WebDataBinder binder) {
    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
    dateFormat.setLenient(false);

    // true passed to CustomDateEditor constructor means convert empty String to null
    binder.registerCustomEditor(Date.class, new CustomDateEditor(dateFormat, true));
}

Answered By - Chin Huang
Answer Checked By - Cary Denson (JavaFixing Admin)