Deprecate unused method

spring-websocket/src/main/java/org/springframework/web/socket/WebSocketHttpHeaders.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,6 +26,7 @@ import java.util.Set;
 import org.springframework.http.HttpHeaders;
 import org.springframework.lang.Nullable;
 import org.springframework.util.CollectionUtils;
+import org.springframework.util.MultiValueMap;
 
 /**
  * An {@link org.springframework.http.HttpHeaders} variant that adds support for
@@ -56,7 +57,7 @@ public class WebSocketHttpHeaders extends HttpHeaders {
 	 * Create a new instance.
 	 */
 	public WebSocketHttpHeaders() {
-		this(new HttpHeaders(), false);
+		this(new HttpHeaders());
 	}
 
 	/**
@@ -65,21 +66,16 @@ public class WebSocketHttpHeaders extends HttpHeaders {
 	 * @param headers the HTTP headers to wrap
 	 */
 	public WebSocketHttpHeaders(HttpHeaders headers) {
-		this(headers, false);
+		this.headers = headers;
-	}
-
-	/**
-	 * Private constructor that can create read-only {@code WebSocketHttpHeader} instances.
-	 */
-	private WebSocketHttpHeaders(HttpHeaders headers, boolean readOnly) {
-		this.headers = readOnly ? HttpHeaders.readOnlyHttpHeaders(headers) : headers;
 	}
 
 	/**
 	 * Returns {@code WebSocketHttpHeaders} object that can only be read, not written to.
+	 * @deprecated as of 5.2.7 in favor of {@link HttpHeaders#readOnlyHttpHeaders(MultiValueMap)}
 	 */
+	@Deprecated
 	public static WebSocketHttpHeaders readOnlyWebSocketHttpHeaders(WebSocketHttpHeaders headers) {
-		return new WebSocketHttpHeaders(headers, true);
+		return new WebSocketHttpHeaders(HttpHeaders.readOnlyHttpHeaders(headers));
 	}