diff --git a/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/JettyRequestUpgradeStrategy.java b/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/JettyRequestUpgradeStrategy.java
index f688756b22a87bd030a1fbc1f020dc39740173c8..c8c3f8ac12bdb05940f885c7539abe28ebcc1f78 100644
--- a/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/JettyRequestUpgradeStrategy.java
+++ b/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/JettyRequestUpgradeStrategy.java
@@ -18,7 +18,6 @@ package org.springframework.web.reactive.socket.server.upgrade;
 
 import java.io.IOException;
 import java.util.function.Supplier;
-
 import javax.servlet.ServletContext;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
diff --git a/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/TomcatRequestUpgradeStrategy.java b/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/TomcatRequestUpgradeStrategy.java
index fb4ef36dd07e7ade942e6cbbd69747b0a6436911..0cd55ac797116252ed486067ea6570b7de1e945e 100644
--- a/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/TomcatRequestUpgradeStrategy.java
+++ b/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/TomcatRequestUpgradeStrategy.java
@@ -19,7 +19,6 @@ package org.springframework.web.reactive.socket.server.upgrade;
 import java.io.IOException;
 import java.util.Collections;
 import java.util.function.Supplier;
-
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
diff --git a/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/UndertowRequestUpgradeStrategy.java b/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/UndertowRequestUpgradeStrategy.java
index 56b69515a4b7c659d3bec8e1da68feeb38494b06..faacd3aa23614b36b5942ece8584b6fe70ef06e1 100644
--- a/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/UndertowRequestUpgradeStrategy.java
+++ b/spring-webflux/src/main/java/org/springframework/web/reactive/socket/server/upgrade/UndertowRequestUpgradeStrategy.java
@@ -35,7 +35,6 @@ import org.springframework.http.server.reactive.AbstractServerHttpRequest;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.http.server.reactive.ServerHttpRequestDecorator;
 import org.springframework.lang.Nullable;
-import org.springframework.util.Assert;
 import org.springframework.web.reactive.socket.HandshakeInfo;
 import org.springframework.web.reactive.socket.WebSocketHandler;
 import org.springframework.web.reactive.socket.adapter.UndertowWebSocketHandlerAdapter;