Polishing

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

@@ -468,9 +468,9 @@ public class HttpHeaders implements Serializable {
 	 * <p>If the supplied {@code HttpHeaders} instance is a
 	 * {@linkplain #readOnlyHttpHeaders(HttpHeaders) read-only}
 	 * {@code HttpHeaders} wrapper, it will be unwrapped to ensure that the
-	 * {@code HttpHeaders} instance created by this constructor is mutable.
+	 * {@code HttpHeaders} instance created by this constructor is mutable. Once
-	 * Once the writable instance is mutated, the read-only instance is
+	 * the writable instance is mutated, the read-only instance is likely to be
-	 * likely to be out of sync and should be discarded.
+	 * out of sync and should be discarded.
 	 * @param httpHeaders the headers to expose
 	 * @since 7.0
 	 * @see #copyOf(HttpHeaders)

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

@@ -32,9 +32,10 @@ import org.springframework.util.CollectionUtils;
 import org.springframework.util.MultiValueMap;
 
 /**
- * {@code HttpHeaders} object that can only be read, not written to.
+ * {@code HttpHeaders} variant that can only be read, not written to.
- * <p>This caches the parsed representations of the "Accept" and "Content-Type" headers
+ *
- * and will get out of sync with the backing map it is mutated at runtime.
+ * <p>This caches the parsed representations of the "Accept" and "Content-Type"
+ * headers and will get out of sync with the backing map if it is mutated at runtime.
  *
  * @author Brian Clozel
  * @author Sam Brannen
@@ -44,11 +45,13 @@ class ReadOnlyHttpHeaders extends HttpHeaders {
 
 	private static final long serialVersionUID = -8578554704772377436L;
 
+
 	private @Nullable MediaType cachedContentType;
 
 	@SuppressWarnings("serial")
 	private @Nullable List<MediaType> cachedAccept;
 
+
 	ReadOnlyHttpHeaders(MultiValueMap<String, String> headers) {
 		super(headers);
 	}
@@ -138,7 +141,6 @@ class ReadOnlyHttpHeaders extends HttpHeaders {
 		return Collections.unmodifiableSet(super.headerNames());
 	}
 
-
 	@Override
 	public List<String> put(String key, List<String> value) {
 		throw new UnsupportedOperationException();