add exception handler

spring-security-login-and-registration/src/main/java/org/baeldung/web/controller/RegistrationController.java

@@ -19,6 +19,7 @@ import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.MessageSource;
+import org.springframework.http.MediaType;
 import org.springframework.mail.MailAuthenticationException;
 import org.springframework.mail.SimpleMailMessage;
 import org.springframework.mail.javamail.JavaMailSender;
@@ -35,6 +36,7 @@ import org.springframework.web.bind.annotation.ModelAttribute;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.servlet.ModelAndView;
 
 @Controller
@@ -121,7 +123,6 @@ public class RegistrationController {
     public String resendRegistrationToken(final HttpServletRequest request, final Model model, @RequestParam("token") final String existingToken) {
         final Locale locale = request.getLocale();
         final VerificationToken newToken = userService.generateNewVerificationToken(existingToken);
-
         final User user = userService.getUser(newToken.getToken());
         try {
             final String appUrl = request.getServerName() + ":" + request.getServerPort() + request.getContextPath();
@@ -135,32 +136,19 @@ public class RegistrationController {
             model.addAttribute("message", e.getLocalizedMessage());
             return "redirect:/login.html?lang=" + locale.getLanguage();
         }
-
         model.addAttribute("message", messages.getMessage("message.resendToken", null, locale));
         return "redirect:/login.html?lang=" + locale.getLanguage();
     }
 
-    @RequestMapping(value = "/user/resendRegistrationToken2", method = RequestMethod.GET)
+    @RequestMapping(value = "/user/resendRegistrationToken2", method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
-    public String resendRegistrationToken2(final HttpServletRequest request, final Model model, @RequestParam("token") final String existingToken) {
+    public @ResponseBody String resendRegistrationToken2(final HttpServletRequest request, final Model model, @RequestParam("token") final String existingToken) {
-        final Locale locale = request.getLocale();
         final VerificationToken newToken = userService.generateNewVerificationToken(existingToken);
-
         final User user = userService.getUser(newToken.getToken());
-        try {
         final String appUrl = request.getServerName() + ":" + request.getServerPort() + request.getContextPath();
         final SimpleMailMessage email = constructResetVerificationTokenEmail(appUrl, request.getLocale(), newToken, user);
+        System.out.println(email.getText());
         mailSender.send(email);
-        } catch (final MailAuthenticationException e) {
+        return messages.getMessage("message.resendToken", null, request.getLocale());
-            LOGGER.debug("MailAuthenticationException", e);
-            return "redirect:/emailError.html?lang=" + locale.getLanguage();
-        } catch (final Exception e) {
-            LOGGER.debug(e.getLocalizedMessage(), e);
-            model.addAttribute("message", e.getLocalizedMessage());
-            return "redirect:/login.html?lang=" + locale.getLanguage();
-        }
-
-        model.addAttribute("message", messages.getMessage("message.resendToken", null, locale));
-        return "redirect:/login.html?lang=" + locale.getLanguage();
     }
 
     @RequestMapping(value = "/user/resetPassword", method = RequestMethod.POST)

spring-security-login-and-registration/src/main/java/org/baeldung/web/error/RestResponseEntityExceptionHandler.java

@@ -0,0 +1,35 @@
+package org.baeldung.web.error;
+
+import org.springframework.mail.MailAuthenticationException;
+import org.springframework.web.bind.annotation.ControllerAdvice;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.ResponseBody;
+import org.springframework.web.context.request.WebRequest;
+import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+@ControllerAdvice
+public class RestResponseEntityExceptionHandler extends ResponseEntityExceptionHandler {
+
+    public RestResponseEntityExceptionHandler() {
+        super();
+    }
+
+    // API
+
+    // 500
+    @ExceptionHandler({ MailAuthenticationException.class })
+    public @ResponseBody String handleMail(final RuntimeException ex, final WebRequest request) throws JsonProcessingException {
+        logger.error("500 Status Code", ex);
+        return new ObjectMapper().writeValueAsString(ex.getClass().toString());
+    }
+
+    @ExceptionHandler({ NullPointerException.class, IllegalArgumentException.class, IllegalStateException.class })
+    public @ResponseBody String handleInternal(final RuntimeException ex, final WebRequest request) throws JsonProcessingException {
+        logger.error("500 Status Code", ex);
+        return new ObjectMapper().writeValueAsString(ex.getClass().toString());
+    }
+
+}

spring-security-login-and-registration/src/main/webapp/WEB-INF/view/badUser.jsp

@@ -23,12 +23,28 @@ code="label.form.loginSignUp"></spring:message></a>
 <c:if test="${param.expired}">
 <br>
 <h1>${label.form.resendRegistrationToken}</h1>
-<a href="<c:url value="/user/resendRegistrationToken">
+<button onclick="resendToken()">
-			<c:param name="token" value="${param.token}"/>
-		 </c:url>">
 	<spring:message code="label.form.resendRegistrationToken"></spring:message>
-</a>
+</button>
-</c:if>
 
+
+<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js"></script>
+<script type="text/javascript">
+function resendToken(){
+	$.get("<c:url value="/user/resendRegistrationToken2"><c:param name="token" value="${param.token}"/></c:url>", function(data){
+        if(data.indexOf("MailAuthenticationException") > -1)
+        {
+        	window.location.href = "<c:url value="/emailError.html"></c:url>";
+        }
+        else if(data.indexOf("Exception") > -1){
+        	window.location.href = "<c:url value="/login"><c:param name="message" value="Error"/></c:url>";
+        }
+        else{
+        	window.location.href = "<c:url value="/login"></c:url>" + "message=" + data;
+        }
+    });
+}
+</script>
+</c:if>
 </body>
 </html>