How to Fix Spring Boot 3 Trailing Slash URL Mismatch After Upgrade

In this article we discuss the changes to URL matching introduced in Spring Boot 3 (Spring 6) and how they affect existing applications after upgrading from 2.x.

Problem Description

After upgrading a project to Spring Boot 3.1, requests that previously matched a controller no longer work when the URL ends with a trailing slash.

Problem Reproduction

@RestController
public class DemoController {
    @GetMapping("/demo/path")
    public String path() {
        return "Hello lengleng";
    }
}

Request

/demo/path

returns the expected result.

Request

/demo/path/

returns 404.

Solution

Method 1: Enable trailing‑slash matching (not recommended)

public class WebConfiguration implements WebMvcConfigurer {
    @Override
    public void configurePathMatch(PathMatchConfigurer configurer) {
        configurer.setUseTrailingSlashMatch(true);
    }
}

The

setUseTrailingSlashMatch

method is deprecated in Spring 6 and will be removed in future versions.

Method 2: Create a filter to strip the trailing slash

public class TrailingSlashRedirectFilter implements Filter {
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        HttpServletRequest httpRequest = (HttpServletRequest) request;
        String path = httpRequest.getRequestURI();
        if (path.endsWith("/")) {
            String newPath = path.substring(0, path.length() - 1);
            HttpServletRequest newRequest = new CustomHttpServletRequestWrapper(httpRequest, newPath);
            chain.doFilter(newRequest, response);
        } else {
            chain.doFilter(request, response);
        }
    }

    private static class CustomHttpServletRequestWrapper extends HttpServletRequestWrapper {
        private final String newPath;
        public CustomHttpServletRequestWrapper(HttpServletRequest request, String newPath) {
            super(request);
            this.newPath = newPath;
        }
        @Override
        public String getRequestURI() {
            return newPath;
        }
        @Override
        public StringBuffer getRequestURL() {
            StringBuffer url = new StringBuffer();
            url.append(getScheme()).append("://").append(getServerName()).append(":")
               .append(getServerPort()).append(newPath);
            return url;
        }
    }
}

Method 3: Nginx redirect configuration

location / {
    if ($request_uri ~ ^(.+)/$) {
        return 301 $1;
    }
    proxy_pass http://localhost:8080;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}

Advanced: Optimization in PIG microservice architecture

When using Spring Cloud Gateway, the request‑path interceptor rewrites URLs and automatically removes the trailing slash, preventing the 404 error.