How to check if a particular row has validation error for a multi row validation in Spring using BindingResult - spring

Question

The current logic will check if the BindingResult has errors and the display the data and errors in a jsp.
The logic needed is to check Errors for each row and display only those rows containing validation errors and update the rows which don't have validation errors.
#Autowired
private IncidentExtractStgService incidentExtractStgService;
#RequestMapping(value = "/validatingIncidentList", method = RequestMethod.POST)
public String ValidateIncidentList( #Valid #ModelAttribute("incidentsForm") IncidentsForm incidentsForm,
BindingResult bindingResult,RedirectAttributes redirectAttributes) {
if (bindingResult.hasErrors()) {
for(ObjectError error: bindingResult.getAllErrors()){
System.out.println(error);
}
redirectAttributes.addFlashAttribute("org.springframework.validation.BindingResult.incidentsForm", bindingResult);
redirectAttributes.addFlashAttribute("incidentsForm", incidentsForm);
return "redirect:/validateIncidentList";
}
else
{
for(IncidentExtractStg ie : incidentsForm.getIncidents()) {
ie.setValidated(1);
incidentExtractStgService.update(ie);
System.out.println(ie.getNumber()+" "+ie.getWaitTime());
}
return "redirect:/validateIncidentList";
}
The below code snippet will check if the model contains attribute "incidetsForm",if so will send the same to example.jsp which in-turn will display the data and validation errors.
#RequestMapping(value = "/validateIncidentList", method = RequestMethod.GET)
public String incidentList(Model model) {
if (!model.containsAttribute("incidentsForm")) {
List<IncidentExtractStg> incidents = incidentExtractStgDao.validateList();
incidentsForm.setIncidents(incidents);
model.addAttribute("incidentsForm", incidentsForm);
return "example";
}
model.addAttribute("errormessage","Please Check the Validation Errors column for Errors");
return "example";
}
Example.jsp code snippet
<c:forEach var="ie" items="${incidentsForm.incidents}" varStatus="status">
<tr>
<td><form:input path="incidents[${status.index}].id" value="${ie.id}" readonly ="true"/></td>
<td><form:errors path="incidents[${status.index}].id" cssClass="error" /></td>
<td><form:input path="incidents[${status.index}].number" value="${ie.number}"/></td>
<td><form:errors path="incidents[${status.index}].number" cssClass="error" /></td>
</tr>
IncidentsForm.java:
import java.util.List;
import javax.validation.Valid;
import com.infosys.sla.model.IncidentExtractStg;
public class IncidentsForm {
#Valid
private List<IncidentExtractStg> incidents;
public List<IncidentExtractStg> getIncidents() {
return incidents;
}
public void setIncidents(List<IncidentExtractStg> incidents) {
this.incidents = incidents;
}
}
IncidentExtractStg.java snippet
#Entity
#Table(name="incident_extract_stg")
public class IncidentExtractStg {
#Id
#Column(name="ies_id")
private int id;
#NotBlank(message="number cannot be empty")
#Pattern(regexp="[A-Za-z0-9]*",message="number can contain only alphabets and numbers")
#Column(name="ies_number")
private String number;

Answer 1

First of all, if I were you I will extract all the logic inside a Service Layer. To proceed, you could create an interface IncidentService and its own concrete implementation IncidentServiceImpl in which you can safely will handle your needs. Controllers are definitely not done to do everything.
Then, what are your needs?
"check Errors for each row and display only those rows containing validation errors and update the rows which don't have validation errors"
A method inside your Service Layer could be like that:
public void handleErrors(IncidentsForm incidentsForm, BindingResult bindingResult){
List<String> fieldsInErrorState = new ArrayList<String>(10);
if (bindingResult.hasErrors()) { //
Map<String, Object> bindingModel = bindingResult.getModel();
for (Map.Entry<String, Object> entry : bindingModel.entrySet()) {
String key = entry.getKey();
//Object value = entry.getValue(); you don't need to parse that unless you want specific domain model handlers to run
//you need to store the key as a form field which is in error state
fieldsInErrorState.add(key);
//you already have all the stuff to parse and display errors in your JSP
//thanksfully to bindingResult and JSTL tags.
}
ContactMessageForm cmForm2 = new ContactMessageForm();
// get the list of the fields inside your form
Field[] declaredFields = ContactMessageForm.class.getDeclaredFields();
for (Field field : declaredFields) {
if (!fieldsInErrorState.contains(field.getName())) {
if (field.getName().equalsIgnoreCase("firstname")) {
cmForm2.setFirstname(contactMessageForm.getFirstname());
}
if (field.getName().equalsIgnoreCase("lastname")) {
cmForm2.setLastname(contactMessageForm.getLastname());
}
//etc for each properties of your form object.
}
// then store your dbmodel object
// BUT i think you must be carefull to your data integrity... It is maybe not safe to save an object like that with bypassing some stuff...
// Your form was built like that maybe for a good reason looking at your objects graph.
// If your form is too big, then split it in small parts, it will be much easy to handle, to update, and to work with daily.
}
}
}
Of course you need to customize that code, don't forget to add the throws IntrospectionException to your service method, and you are on the good way.
Cheers!

Answer 2

As the logic is to display only those rows containing validation errors, a new List is created to store the rows which are having at least one validation error.
A new BindingResult is created to store the Errors against the index of the new List.(If this is not done then the error message wont be displayed against the displayed row).
The below logic is to check for field error against each field of the row and from the jsp you can see the filed name has "incidents[${status.index}].id".
- Counter i to get the row count
- Counter j is to set the index for BindingResult.
BeanPropertyBindingResult result2 = new BeanPropertyBindingResult(incidentsForm, bindingResult.getObjectName();
List<IncidentExtractStg> incidents= new ArrayList<IncidentExtractStg>();
int i=0;// to get the row count
int j=0;// to set the index
for(IncidentExtractStg ies : incidentsForm.getIncidents())
{
int count=0;
Field[] declaredFields = IncidentExtractStg.class.getDeclaredFields();
for (Field field : declaredFields)
{
if (bindingResult.hasFieldErrors("incidents["+i+"]."+field.getName()))
{
for (FieldError error: bindingResult.getFieldErrors("incidents["+i+"]."+field.getName()))
{
result2.addError(new FieldError(error.getObjectName(), "incidents["+j+"]."+field.getName(), error.getRejectedValue(), error.isBindingFailure(), error.getCodes(), error.getArguments(), error.getDefaultMessage()));
}
count++;
}
}
if(count>0)
{
j++;
incidents.add(ies);
}
else
{
ies.setValidated(1);
incidentExtractStgService.update(ies);
}
i++;
}
i=0;
j=0;
if (bindingResult.hasErrors()) {
incidentsForm.setIncidents(incidents);
System.out.println("error block");
for (FieldError error: result2.getFieldErrors()) {
System.out.println("field errors are "+error.getField());
System.out.println("field errors are "+error);
}
redirectAttributes.addFlashAttribute("org.springframework.validation.BindingResult.incidentsForm", result2);
redirectAttributes.addFlashAttribute("incidentsForm", incidentsForm);
return "redirect:/validateIncidentList";
}
E.g: If in row number 30 ,incidents[30].number field has validation error. Then i=30 and count>0 and j=0.
Hence the entire row incidents[30] will be saved at index 0 in the newly initialized list and the bindingresult will also be added at index 0. If the J is not being set to the result2 and bindingresult is used then it will still point to index 30 and error message will not be displayed against the field which is now stored at index 0.
Now this updated IncidentsForm and result2 will be send to jsp page which will display only those rows having validations errors and there respective error messages.