Started part 6

src/main/java/io/zipcoder/tc_spring_poll_application/controller/PollController.java

 import org.springframework.web.bind.annotation.*;
 import org.springframework.web.servlet.support.ServletUriComponentsBuilder;
 
+import javax.validation.Valid;
 import java.net.URI;
 
 @RestController// marks entity as a controller following REST specs
         return new ResponseEntity<>(newHeaders, HttpStatus.CREATED);
     }
 
+    @Valid
     @RequestMapping(value="/polls/{pollId}", method=RequestMethod.GET)
     public ResponseEntity<?> getPoll(@PathVariable Long pollId) {
         verifyPoll(pollId);
         return new ResponseEntity<> (p, HttpStatus.OK);
     }
 
+    @Valid
     @RequestMapping(value="/polls/{pollId}", method=RequestMethod.PUT)
     public ResponseEntity<?> updatePoll(@RequestBody Poll poll, @PathVariable Long pollId) {
         // Save the entity
 
     public void verifyPoll(Long pollId){
         Poll poll = pollRepository.findOne(pollId);
-        if(pollId == null){
-            throw new ResourceNotFoundException("The given poll id" + pollId + "does not exist!");
+        if(poll == null){
+            throw new ResourceNotFoundException("The given poll id " + pollId + " does not exist!");
         }
     }
 

src/main/java/io/zipcoder/tc_spring_poll_application/domain/Poll.java

 package io.zipcoder.tc_spring_poll_application.domain;
 
+import org.hibernate.validator.constraints.NotEmpty;
+
 import javax.persistence.*;
+import javax.validation.constraints.Size;
 import java.util.Set;
 
 @Entity
     @Column(name = "POLL_ID")
     private Long id;
 
+    @NotEmpty
     @Column(name = "QUESTION")
     private String question;
 
+    @Size(min=2, max = 6)
     @OneToMany(cascade = CascadeType.ALL)// indicates that a Poll instance can contain zero or more Option instances. The CascadeType.All indicates that any database operations such as persist, remove, or merge on a Poll instance needs to be propagated to all related Option instances
     @JoinColumn(name = "POLL_ID")// indicates this entity is the owner of the relationship. It has a key to the column with options
     @OrderBy// orders by ASC default

src/main/java/io/zipcoder/tc_spring_poll_application/error/ErrorDetail.java

 package io.zipcoder.tc_spring_poll_application.error;
 
+import java.util.List;
+import java.util.Map;
+
 public class ErrorDetail {
 
     private String title; // title of error condition
     private int status; // HTTP status code for current request
     private String detail; // short readable description of error
-    private long timeStamp; // time in milliseconds when error occured
+    private long timeStamp; // time in milliseconds when error occurred
     private String developerMessage; // detailed info as such exception class or trace
+    private Map<String, List<ValidationError>> errors;
 
     public String getTitle() {
         return title;
     public void setDeveloperMessage(String developerMessage) {
         this.developerMessage = developerMessage;
     }
+
+    public Map<String, List<ValidationError>> getErrors() {
+        return errors;
+    }
+
+    public void setErrors(Map<String, List<ValidationError>> errors) {
+        this.errors = errors;
+    }
 }

src/main/java/io/zipcoder/tc_spring_poll_application/error/ValidationError.java

+package io.zipcoder.tc_spring_poll_application.error;
+
+public class ValidationError {
+
+    private String code;
+    private String message;
+
+    public String getCode() {
+        return code;
+    }
+
+    public void setCode(String code) {
+        this.code = code;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public void setMessage(String message) {
+        this.message = message;
+    }
+}

src/main/java/io/zipcoder/tc_spring_poll_application/exception/RestExceptionHandler.java

 package io.zipcoder.tc_spring_poll_application.exception;
 
 import io.zipcoder.tc_spring_poll_application.error.ErrorDetail;
+import io.zipcoder.tc_spring_poll_application.error.ValidationError;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.MessageSource;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
+import org.springframework.validation.FieldError;
+import org.springframework.web.bind.MethodArgumentNotValidException;
 import org.springframework.web.bind.annotation.ControllerAdvice;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 
 import javax.servlet.http.HttpServletRequest;
+import java.util.ArrayList;
 import java.util.Date;
+import java.util.List;
 
 @ControllerAdvice
 public class RestExceptionHandler {
 
+    @Autowired
+    MessageSource messageSource;
+
     @ExceptionHandler(ResourceNotFoundException.class)
     public ResponseEntity<?> handleResourceNotFoundException(ResourceNotFoundException rnfe, HttpServletRequest request){
         //make error detail object and fill it?
         errorDetail.setDeveloperMessage(rnfe.getClass().getName());
         return new ResponseEntity<>(errorDetail, null,  HttpStatus.NOT_FOUND);
     }
+
+    @ExceptionHandler(MethodArgumentNotValidException.class)
+    public ResponseEntity<?> handleValicationError(MethodArgumentNotValidException manve, HttpServletRequest request){
+        ErrorDetail errorDetail = new ErrorDetail();
+        errorDetail.setTitle("Validation Failed");
+        errorDetail.setStatus(HttpStatus.BAD_REQUEST.value());
+        errorDetail.setDetail("Input validation failed");
+        errorDetail.setTimeStamp(new Date().getTime());
+        errorDetail.setDeveloperMessage(manve.getClass().getName());
+
+        String requestPath = (String) request.getAttribute("javax.servlet.error. request_uri");
+        if(requestPath == null) {
+            requestPath = request.getRequestURI();
+        }
+
+        List<FieldError> fieldErrors =  manve.getBindingResult().getFieldErrors();
+        for(FieldError fe : fieldErrors) {
+
+            List<ValidationError> validationErrorList = errorDetail.getErrors().get(fe.getField());
+            if(validationErrorList == null) {
+                validationErrorList = new ArrayList<>();
+                errorDetail.getErrors().put(fe.getField(), validationErrorList);
+            }
+            ValidationError validationError = new ValidationError();
+            validationError.setCode(fe.getCode());
+            validationError.setMessage(messageSource.getMessage(fe, null));
+            validationErrorList.add(validationError);
+        }
+        return new ResponseEntity<>(errorDetail, HttpStatus.BAD_REQUEST);
+    }
 }

src/main/resources/messages.properties

+NotEmpty.poll.question=Question is a required field
+Size.poll.options=Options must be greater than {2} and less than {1}