chore: Update constructor references with backedBy method.

Author: craftmaster2190

Diff for: spring-web/src/main/java/org/springframework/http/HttpHeaders.java

@@ -452,7 +452,7 @@ public HttpHeaders() {
 	 * headers map structures, primarily for internal use within the framework.
 	 * @param headers the headers map (expected to operate with case-insensitive keys)
 	 * @since 5.1
-	 * @deprecated Will be made private in favor of {@link #backedBy(MultiValueMap)} in a future release.
+	 * @deprecated Will be made default visibility in favor of {@link #backedBy(MultiValueMap)} in a future release.
 	 */
 	@Deprecated
 	public HttpHeaders(MultiValueMap<String, String> headers) {
@@ -501,6 +501,7 @@ public HttpHeaders(HttpHeaders httpHeaders) {
 	 * headers map structures, primarily for internal use within the framework.
 	 * @param headers the headers map (expected to operate with case-insensitive keys)
 	 */
+	@SuppressWarnings("deprecation") // @Deprecated wll be removed when visibility is changed.
 	public static HttpHeaders backedBy(MultiValueMap<String, String> headers) {
 		return new HttpHeaders(headers);
 	}
@@ -513,8 +514,9 @@ public static HttpHeaders backedBy(MultiValueMap<String, String> headers) {
 	 * likely to be out of sync and should be discarded.
 	 * @param httpHeaders the headers to expose
 	 */
+	@SuppressWarnings("deprecation") // @Deprecated wll be removed when visibility is changed.
 	public static HttpHeaders backedBy(HttpHeaders httpHeaders) {
-		return backedBy(httpHeaders.headers);
+		return new HttpHeaders(httpHeaders);
 	}
 
 	/**

Diff for: spring-web/src/main/java/org/springframework/http/ReadOnlyHttpHeaders.java

@@ -50,7 +50,7 @@ class ReadOnlyHttpHeaders extends HttpHeaders {
 	@SuppressWarnings("serial")
 	private @Nullable List<MediaType> cachedAccept;
 
-
+	@SuppressWarnings("deprecation") // @Deprecated wll be removed when visibility is changed.
 	ReadOnlyHttpHeaders(MultiValueMap<String, String> headers) {
 		super(headers);
 	}

Diff for: spring-web/src/main/java/org/springframework/http/codec/multipart/PartHttpMessageWriter.java

@@ -91,7 +91,7 @@ public Mono<Void> write(Publisher<? extends Part> parts,
 	}
 
 	private <T> Flux<DataBuffer> encodePart(byte[] boundary, Part part, DataBufferFactory bufferFactory) {
-		HttpHeaders headers = new HttpHeaders(part.headers());
+		HttpHeaders headers = HttpHeaders.backedBy(part.headers());
 
 		String name = part.name();
 		if (!headers.containsHeader(HttpHeaders.CONTENT_DISPOSITION)) {

Diff for: spring-web/src/main/java/org/springframework/http/server/reactive/JettyCoreServerHttpRequest.java

@@ -56,7 +56,7 @@ public JettyCoreServerHttpRequest(Request request, JettyDataBufferFactory dataBu
 		super(HttpMethod.valueOf(request.getMethod()),
 				request.getHttpURI().toURI(),
 				request.getContext().getContextPath(),
-				new HttpHeaders(new JettyHeadersAdapter(request.getHeaders())));
+				HttpHeaders.backedBy(new JettyHeadersAdapter(request.getHeaders())));
 		this.dataBufferFactory = dataBufferFactory;
 		this.request = request;
 	}

Diff for: spring-web/src/main/java/org/springframework/http/server/reactive/JettyCoreServerHttpResponse.java

@@ -56,7 +56,7 @@ class JettyCoreServerHttpResponse extends AbstractServerHttpResponse implements
 
 
 	public JettyCoreServerHttpResponse(Response response, JettyDataBufferFactory dataBufferFactory) {
-		super(dataBufferFactory, new HttpHeaders(new JettyHeadersAdapter(response.getHeaders())));
+		super(dataBufferFactory, HttpHeaders.backedBy(new JettyHeadersAdapter(response.getHeaders())));
 		this.response = response;
 
 		// remove all existing cookies from the response and add them to the cookie map, to be added back later

Diff for: spring-web/src/main/java/org/springframework/http/server/reactive/ReactorNetty2ServerHttpRequest.java

@@ -71,7 +71,7 @@ public ReactorNetty2ServerHttpRequest(HttpServerRequest request, Netty5DataBuffe
 			throws URISyntaxException {
 
 		super(HttpMethod.valueOf(request.method().name()), initUri(request), "",
-				new HttpHeaders(new Netty5HeadersAdapter(request.requestHeaders())));
+				HttpHeaders.backedBy(new Netty5HeadersAdapter(request.requestHeaders())));
 		Assert.notNull(bufferFactory, "DataBufferFactory must not be null");
 		this.request = request;
 		this.bufferFactory = bufferFactory;

Diff for: spring-web/src/main/java/org/springframework/http/server/reactive/ReactorNetty2ServerHttpResponse.java

@@ -58,7 +58,7 @@ class ReactorNetty2ServerHttpResponse extends AbstractServerHttpResponse impleme
 
 
 	public ReactorNetty2ServerHttpResponse(HttpServerResponse response, DataBufferFactory bufferFactory) {
-		super(bufferFactory, new HttpHeaders(new Netty5HeadersAdapter(response.responseHeaders())));
+		super(bufferFactory, HttpHeaders.backedBy(new Netty5HeadersAdapter(response.responseHeaders())));
 		Assert.notNull(response, "HttpServerResponse must not be null");
 		this.response = response;
 	}

Diff for: spring-web/src/main/java/org/springframework/http/server/reactive/ReactorServerHttpRequest.java

@@ -68,7 +68,7 @@ public ReactorServerHttpRequest(HttpServerRequest request, NettyDataBufferFactor
 
 		super(HttpMethod.valueOf(request.method().name()),
 				ReactorUriHelper.createUri(request), request.forwardedPrefix(),
-				new HttpHeaders(new Netty4HeadersAdapter(request.requestHeaders())));
+				HttpHeaders.backedBy(new Netty4HeadersAdapter(request.requestHeaders())));
 		Assert.notNull(bufferFactory, "DataBufferFactory must not be null");
 		this.request = request;
 		this.bufferFactory = bufferFactory;

Diff for: spring-web/src/main/java/org/springframework/http/server/reactive/ReactorServerHttpResponse.java

@@ -57,7 +57,7 @@ class ReactorServerHttpResponse extends AbstractServerHttpResponse implements Ze
 
 
 	public ReactorServerHttpResponse(HttpServerResponse response, DataBufferFactory bufferFactory) {
-		super(bufferFactory, new HttpHeaders(new Netty4HeadersAdapter(Objects.requireNonNull(response,
+		super(bufferFactory, HttpHeaders.backedBy(new Netty4HeadersAdapter(Objects.requireNonNull(response,
 				"HttpServerResponse must not be null").responseHeaders())));
 		this.response = response;
 	}

Diff for: spring-web/src/main/java/org/springframework/http/server/reactive/ServletServerHttpRequest.java

@@ -168,7 +168,7 @@ private static HttpHeaders initHeaders(HttpHeaders headerValues, HttpServletRequ
 			String requestContentType = request.getContentType();
 			if (StringUtils.hasLength(requestContentType)) {
 				contentType = MediaType.parseMediaType(requestContentType);
-				headers = new HttpHeaders(headerValues);
+				headers = HttpHeaders.backedBy(headerValues);
 				headers.setContentType(contentType);
 			}
 		}
@@ -184,7 +184,7 @@ private static HttpHeaders initHeaders(HttpHeaders headerValues, HttpServletRequ
 		if (headerValues.getFirst(HttpHeaders.CONTENT_TYPE) == null) {
 			int contentLength = request.getContentLength();
 			if (contentLength != -1) {
-				headers = (headers != null ? headers : new HttpHeaders(headerValues));
+				headers = (headers != null ? headers : HttpHeaders.backedBy(headerValues));
 				headers.setContentLength(contentLength);
 			}
 		}

Diff for: spring-web/src/main/java/org/springframework/http/server/reactive/TomcatHttpHandlerAdapter.java

@@ -96,7 +96,7 @@ private static HttpHeaders createTomcatHttpHeaders(HttpServletRequest request) {
 					ReflectionUtils.getField(COYOTE_REQUEST_FIELD, requestFacade);
 			Assert.state(connectorRequest != null, "No Tomcat connector request");
 			Request tomcatRequest = connectorRequest.getCoyoteRequest();
-			return new HttpHeaders(new TomcatHeadersAdapter(tomcatRequest.getMimeHeaders()));
+			return HttpHeaders.backedBy(new TomcatHeadersAdapter(tomcatRequest.getMimeHeaders()));
 		}
 
 		private static RequestFacade getRequestFacade(HttpServletRequest request) {
@@ -140,7 +140,7 @@ private static HttpHeaders createTomcatHttpHeaders(HttpServletResponse response)
 			Assert.state(connectorResponse != null, "No Tomcat connector response");
 			Response tomcatResponse = connectorResponse.getCoyoteResponse();
 			TomcatHeadersAdapter headers = new TomcatHeadersAdapter(tomcatResponse.getMimeHeaders());
-			return new HttpHeaders(headers);
+			return HttpHeaders.backedBy(headers);
 		}
 
 		private static ResponseFacade getResponseFacade(HttpServletResponse response) {

Diff for: spring-web/src/main/java/org/springframework/http/server/reactive/UndertowServerHttpRequest.java

@@ -66,7 +66,7 @@ public UndertowServerHttpRequest(HttpServerExchange exchange, DataBufferFactory
 			throws URISyntaxException {
 
 		super(HttpMethod.valueOf(exchange.getRequestMethod().toString()), initUri(exchange), "",
-				new HttpHeaders(new UndertowHeadersAdapter(exchange.getRequestHeaders())));
+				HttpHeaders.backedBy(new UndertowHeadersAdapter(exchange.getRequestHeaders())));
 		this.exchange = exchange;
 		this.body = new RequestBodyPublisher(exchange, bufferFactory);
 		this.body.registerListeners(exchange);

Diff for: spring-web/src/main/java/org/springframework/http/server/reactive/UndertowServerHttpResponse.java

@@ -70,7 +70,7 @@ class UndertowServerHttpResponse extends AbstractListenerServerHttpResponse impl
 	private static HttpHeaders createHeaders(HttpServerExchange exchange) {
 		Assert.notNull(exchange, "HttpServerExchange must not be null");
 		UndertowHeadersAdapter headersMap = new UndertowHeadersAdapter(exchange.getResponseHeaders());
-		return new HttpHeaders(headersMap);
+		return HttpHeaders.backedBy(headersMap);
 	}