Date range validation - validation

Question

I want to compare two dates (StartDate and EndDate) and check whether one is before the other. The simplest solution is to just do it on the backing bean and "short-circuit" the method.
However this validation does not happen concurrently with the other form validations. For example if I have another field that requires validation (besides the dates) and has invalid input, I will only get a message for that specific field. Only if the other fields are valid will I get the date validation based on the backing bean.
Anyone have a solution?

Answer 1

However this validation does not happen concurrently with the other form validations.
A backing bean action method is indeed not intented to perform input validation.
Anyone have a solution?
Use the right tool for the job; use a normal Validator.
#FacesValidator("dataRangeValidator")
public class DateRangeValidator implements Validator {
// ...
}
Validating multiple input values with a single validator is in turn however indeed a story apart. Basically, you should be grabbing/passing the other component or its value along into the validate() method implementation. In its simplest form, you could use <f:attribute> for this. Assuming that you're using <p:calendar> to pick dates, here's a concrete kickoff example:
<p:calendar id="startDate" binding="#{startDateComponent}" value="#{bean.startDate}" pattern="MM/dd/yyyy" required="true" />
<p:calendar id="endDate" value="#{bean.endDate}" pattern="MM/dd/yyyy" required="true">
<f:validator validatorId="dateRangeValidator" />
<f:attribute name="startDateComponent" value="#{startDateComponent}" />
</p:calendar>
(note the binding attribute, it makes the component available in the EL scope on exactly the given variable name; also note that this example is as-is and that you should absolutely not bind it to a bean property!)
Where the dateRangeValidator look like this:
#FacesValidator("dateRangeValidator")
public class DateRangeValidator implements Validator {
#Override
public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException {
if (value == null) {
return; // Let required="true" handle.
}
UIInput startDateComponent = (UIInput) component.getAttributes().get("startDateComponent");
if (!startDateComponent.isValid()) {
return; // Already invalidated. Don't care about it then.
}
Date startDate = (Date) startDateComponent.getValue();
if (startDate == null) {
return; // Let required="true" handle.
}
Date endDate = (Date) value;
if (startDate.after(endDate)) {
startDateComponent.setValid(false);
throw new ValidatorException(new FacesMessage(
FacesMessage.SEVERITY_ERROR, "Start date may not be after end date.", null));
}
}
}
If you happen to use JSF utility library OmniFaces, then you could also just use its <o:validateOrder> component. The requirement can be achieved as follows without the need for a custom validator:
<p:calendar id="startDate" value="#{bean.startDate}" pattern="MM/dd/yyyy" required="true" />
<p:calendar id="endDate" value="#{bean.endDate}" pattern="MM/dd/yyyy" required="true" />
<o:validateOrder components="startDate endDate" />
See also:
JSF doesn't support cross-field validation, is there a workaround?

Answer 2

if you're using PrimeFaces which can limit a minimum and maximum dates. the user could not choose a greater range this is an example:
<p:calendar id="startDate" value="#{bean.startDate}" maxdate="#{bean.endDate}">
<p:ajax event="dateSelect" update="endDate"/>
</p:calendar>
<p:calendar id="endDate" value="#{bean.endDate}" mindate="#{bean.startDate}" disabled="#{empty bean.startDate}">
<p:ajax event="dateSelect" update="startDate"/>
</p:calendar>

Answer 3

As BalusC solution works only if you have one date range to validate on the form, here is an improvement to allow multiple date range validations:
add another <f:attribute> to the endDate calendar component where you specify the binding attribute name to startDate component:
<f:attribute name="bindingAttributeName" value="startDateComponent" />
then in the validator:
String startDateBindingAttrName = (String) component.getAttributes().get("bindingAttributeName");
UIInput startDateComponent = (UIInput) component.getAttributes().get(startDateBindingAttrName);

Answer 4

Taking the Answer BalusC like Base, and for me use in the future...
This can to set the Interval (Year, Month, Week), the Reference Comparation Initial, or Final.
#FacesValidator("dateRangeValidator")
public class DateRangeValidator implements Validator {
#Override
public void validate(FacesContext facesContext, UIComponent component,
Object value) throws ValidatorException {
UIInput dateIniComponent = (UIInput) component.getAttributes().get("dateIniComponent");
UIInput dateFinComponent = (UIInput) component.getAttributes().get("dateFinComponent");
String range = ((String) component.getAttributes().get("range")).toLowerCase();
String reference = ((String) component.getAttributes().get("reference")).toLowerCase();
if (value == null) {
return;
} else if (value instanceof Date) {
Date dateIni = null;
Date dateFin = null;
if ((dateIniComponent == null) && (dateFinComponent != null)) {
if (!dateFinComponent.isValid()) {
return; //No hay datos contra quien comparar
}
dateFin = (Date) dateFinComponent.getValue();
dateIni = (Date) value;
}
if ((dateFinComponent == null) && (dateIniComponent != null)) {
if (!dateIniComponent.isValid()) {
return; //No hay datos contra quien comparar
}
dateIni = (Date) dateIniComponent.getValue();
dateFin = (Date) value;
}
if ((dateIni != null) && (dateFin != null)) {
Calendar cal = Calendar.getInstance();
cal.setTime(dateIni);
Integer yearIni = cal.get(Calendar.YEAR);
Integer monthIni = cal.get(Calendar.MONTH);
Long daysMonthIni = (long) YearMonth.of(yearIni, monthIni + 1).lengthOfMonth();
Long daysYearIni = (long) cal.getActualMaximum(Calendar.DAY_OF_YEAR);
cal.setTime(dateFin);
Integer yearFin = cal.get(Calendar.YEAR);
Integer monthFin = cal.get(Calendar.MONTH);
Long daysMonthFin = (long) YearMonth.of(yearFin, monthFin + 1).lengthOfMonth();
Long daysYearFin = (long) cal.getActualMaximum(Calendar.DAY_OF_YEAR);
Long daysAllowed =
("year".equals(range) ? ("ini".equals(reference)?daysYearIni:("fin".equals(reference)?daysYearFin:null)) :
("month".equals(range) ? ("ini".equals(reference)?daysMonthIni:("fin".equals(reference)?daysMonthFin:null)) :
("week".equals(range) ? 7 : null)));
Long daysBetweenDates = TimeUnit.DAYS.convert(dateFin.getTime() - dateIni.getTime(), TimeUnit.MILLISECONDS);
if (daysAllowed == null) {
FacesMessage facesMessage
= new FacesMessage(
FacesMessage.SEVERITY_ERROR,
"Rango de fechas mal expresado en el facelet (vista) ",
"Rango de fechas mal expresado en el facelet (vista) ");
throw new ValidatorException(facesMessage);
}
if (dateFin.before(dateIni)) {
FacesMessage facesMessage
= new FacesMessage(
FacesMessage.SEVERITY_ERROR,
"Fecha Final No es posterior a Fecha Inicial ",
"La Fecha Final debe ser posterior a Fecha Inicial");
throw new ValidatorException(facesMessage);
}
if (daysBetweenDates > daysAllowed) {
FacesMessage facesMessage
= new FacesMessage(
FacesMessage.SEVERITY_ERROR,
"Se ha excedido los dias permitidos " + daysAllowed + " entre fechas seleccionadas, entre las fechas hay " + daysBetweenDates + " dias",
"entre las fechas hay " + daysBetweenDates + " dias");
throw new ValidatorException(facesMessage);
}
}
}
}
}
Now in the view
<p:outputLabel value="Date Initial:" for="itHeadDateInitial" />
<p:calendar id="itHeadDateInitial"
navigator="true"
binding="#{bindingDateIniComponent}"
value="#{theBean.DateIni}"
pattern="dd-MM-yyyy" mask="true" >
<f:validator validatorId="dateRangeValidator" />
<f:attribute name="dateFinComponent" value="#{bindingDateFinComponent}" />
<f:attribute name="range" value="year" />
<f:attribute name="reference" value="ini" />
</p:calendar>
<p:outputLabel value="Date Final:" for="itHeadDateFinal" />
<p:calendar id="itHeadDateFinal"
navigator="true"
binding="#{bindingDateFinComponent}"
value="#{theBean.DateFin}"
pattern="dd-MM-yyyy" mask="true" >
<f:validator validatorId="dateRangeValidator" />
<f:attribute name="dateIniComponent" value="#{bindingDateIniComponent}" />
<f:attribute name="range" value="year" />
<f:attribute name="reference" value="ini" />
</p:calendar>