headers.put("Content-Type", Arrays.asList("application/json"));
        headers.put("Content-Length", Arrays.asList("100"));

        response.setHeaders(headers);

        Map<String, List<String>> result = response.getHeaders();
        assertNotNull(result);
        // Headers should be stored in lowercase
        assertTrue(result.containsKey("content-type"));

            return null;
        }

        @Override
        public long getDateHeader(String name) {
            return -1;
        }

        @Override
        public java.util.Enumeration<String> getHeaders(String name) {
            return java.util.Collections.emptyEnumeration();
        }

        @Override
        public java.util.Enumeration<String> getHeaderNames() {

        return contentException;
    }

    /**
     * Sets the headers for the response.
     *
     * @param headers the headers to set.
     */
    public void setHeaders(final Map<String, List<String>> headers) {
        if (headers != null) {
            final Map<String, List<String>> map = new HashMap<>();
            headers.entrySet().stream().filter(e -> e.getKey() != null).forEach(

        public void process(HttpServletRequest request, HttpServletResponse response, FilterChain chain)
                throws IOException, ServletException {
            response.setHeader("Content-Type", "application/json");
            response.setHeader("Cache-Control", "no-cache");
        }
    }

    private static class PatternWebApiManager implements WebApiManager {
        private final String pattern;

            }

            @Override
            public String getHeader(String name) {
                return null;
            }

            @Override
            public java.util.Enumeration<String> getHeaders(String name) {
                return null;
            }

            @Override
            public java.util.Enumeration<String> getHeaderNames() {
                return null;
            }

            }

            @Override
            public String getHeader(String name) {
                return null;
            }

            @Override
            public java.util.Enumeration<String> getHeaders(String name) {
                return null;
            }

            @Override
            public java.util.Enumeration<String> getHeaderNames() {
                return null;
            }

            return -1;
        }

        @Override
        public String getHeader(String name) {
            return null;
        }

        @Override
        public java.util.Enumeration<String> getHeaders(String name) {
            return java.util.Collections.emptyEnumeration();
        }

        @Override
        public java.util.Enumeration<String> getHeaderNames() {

                if (StringUtil.isBlank(responseContentType)) {
                    response.setHeader("Content-Type", "application/json");
                } else {
                    response.setHeader("Content-Type", responseContentType);
                }
                CopyUtil.copy(in, out);
            } catch (final ClientAbortException e) {

        }

        // Set SSE headers
        response.setContentType("text/event-stream");
        response.setCharacterEncoding("UTF-8");
        response.setHeader("Cache-Control", "no-cache");
        response.setHeader("Connection", "keep-alive");
        response.setHeader("X-Accel-Buffering", "no"); // Disable nginx buffering

        try (final PrintWriter writer = response.getWriter()) {

            return new Cookie[0];
        }

        @Override
        public long getDateHeader(String name) {
            return -1;
        }

        @Override
        public Enumeration<String> getHeaders(String name) {
            return null;
        }

        @Override
        public Enumeration<String> getHeaderNames() {
            return null;
        }

        @Override