I recently upgraded my Spring Boot application from 1.5 to 3.4 and Java from 8 to 21. After the upgrade, an AJAX POST request to /set-preferences no longer reaches the controller. Instead, it seems to be handled as a static resource or is being ignored. No changes were made to this method during the upgrade.

Error Log:

.springframework.web.servlet.resource.NoResourceFoundException: No static resource set-preferences. : [.springframework.web.servlet.resource.ResourceHttpRequestHandler.handleRequest(ResourceHttpRequestHandler.java:585), .springframework.web.servlet.mvc.HttpRequestHandlerAdapter.handle(HttpRequestHandlerAdapter.java:52), .springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1088), .springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:978), .springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1014), .springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:914), jakarta.servlet.http.HttpServlet.service(HttpServlet.java:547), .springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885), jakarta.servlet.http.HttpServlet.service(HttpServlet.java:614),

Controller Definition (Unchanged from SB 1.5)

@Controller public class HomeController {
    @RequestMapping(value = "/set-preferences", method = RequestMethod.POST)public String LoginHome(@RequestBody Request request, Model model) {
        UserPreference preference = userPreferenceJsonUtils.convertToObject(
                request.getStrUserPreference(), UserPreference.class);
        setAdditionalUserPreference(preference);
        setResponseMessage(preference, model);
        model.addAttribute("userPreferences", gfeJsonUtils.convertToJson(preference));
        model.addAttribute("User", getUsername());
        return "homePage";
    }
}

AJAX Call (Unchanged from SB 1.5)

var fnAjaxCallToSaveUserPreference = function(Request) {
    $.ajax({
        type: "POST",
        url: "set-preferences/",
        contentType: "application/json",
        async: false,
        data: JSON.stringify(Request),
        cache: false,
        beforeSend: function() {
            $('.loadingImageOpacBg').show();
        },
        success: function(data) {
            if (data !== "") {
                $("#" + "headerId").html(data);
            }
        },
        error: function(xhr, status, error) {
            console.error("AJAX Error:", error);
        }
    });
}

Debugging Steps Taken

Checked Network Tab Shows request sent to /set-preferences/ No 404 error

Questions Why is this AJAX request no longer reaching the controller after upgrading to Spring Boot 3.4? Could this be related to Spring MVC changes in Spring Boot 3.x? What additional debugging steps can I take? Any help would be greatly appreciated!

I recently upgraded my Spring Boot application from 1.5 to 3.4 and Java from 8 to 21. After the upgrade, an AJAX POST request to /set-preferences no longer reaches the controller. Instead, it seems to be handled as a static resource or is being ignored. No changes were made to this method during the upgrade.

Error Log:

.springframework.web.servlet.resource.NoResourceFoundException: No static resource set-preferences. : [.springframework.web.servlet.resource.ResourceHttpRequestHandler.handleRequest(ResourceHttpRequestHandler.java:585), .springframework.web.servlet.mvc.HttpRequestHandlerAdapter.handle(HttpRequestHandlerAdapter.java:52), .springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1088), .springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:978), .springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1014), .springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:914), jakarta.servlet.http.HttpServlet.service(HttpServlet.java:547), .springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885), jakarta.servlet.http.HttpServlet.service(HttpServlet.java:614),

Controller Definition (Unchanged from SB 1.5)

@Controller public class HomeController {
    @RequestMapping(value = "/set-preferences", method = RequestMethod.POST)public String LoginHome(@RequestBody Request request, Model model) {
        UserPreference preference = userPreferenceJsonUtils.convertToObject(
                request.getStrUserPreference(), UserPreference.class);
        setAdditionalUserPreference(preference);
        setResponseMessage(preference, model);
        model.addAttribute("userPreferences", gfeJsonUtils.convertToJson(preference));
        model.addAttribute("User", getUsername());
        return "homePage";
    }
}

AJAX Call (Unchanged from SB 1.5)

var fnAjaxCallToSaveUserPreference = function(Request) {
    $.ajax({
        type: "POST",
        url: "set-preferences/",
        contentType: "application/json",
        async: false,
        data: JSON.stringify(Request),
        cache: false,
        beforeSend: function() {
            $('.loadingImageOpacBg').show();
        },
        success: function(data) {
            if (data !== "") {
                $("#" + "headerId").html(data);
            }
        },
        error: function(xhr, status, error) {
            console.error("AJAX Error:", error);
        }
    });
}

Debugging Steps Taken

Checked Network Tab Shows request sent to /set-preferences/ No 404 error

Questions Why is this AJAX request no longer reaching the controller after upgrading to Spring Boot 3.4? Could this be related to Spring MVC changes in Spring Boot 3.x? What additional debugging steps can I take? Any help would be greatly appreciated!

• ajax
• spring
• spring-boot
• spring-mvc
• java-21

1 Answer 1

Since Spring Boot 3 URLs with and without trailing / are treated as different endpoints.

Change

url: "set-preferences/",

in your AJAX call to

url: "set-preferences",

See https://github/spring-projects/spring-boot/wiki/Spring-Boot-3.0-Migration-Guide#spring-mvc-and-webflux-url-matching-changes for details