src/java.net.http/share/classes/jdk/internal/net/http/common/Utils.java

*** 261,270 ****
--- 261,279 ----
      public static boolean proxyHasDisabledSchemes(boolean tunnel) {
          return tunnel ? ! PROXY_AUTH_TUNNEL_DISABLED_SCHEMES.isEmpty()
                        : ! PROXY_AUTH_DISABLED_SCHEMES.isEmpty();
      }
  
+     // WebSocket connection Upgrade headers
+     private static final String HEADER_CONNECTION = "Connection";
+     private static final String HEADER_UPGRADE    = "Upgrade";
+ 
+     public static final void setWebSocketUpgradeHeaders(HttpRequestImpl request) {
+         request.setSystemHeader(HEADER_UPGRADE, "websocket");
+         request.setSystemHeader(HEADER_CONNECTION, "Upgrade");
+     }
+ 
      public static IllegalArgumentException newIAE(String message, Object... args) {
          return new IllegalArgumentException(format(message, args));
      }
      public static ByteBuffer getBuffer() {
          return ByteBuffer.allocate(BUFSIZE);