diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/TextMessageTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/TextMessageTests.java
index c2009464d26..1254f55f90f 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/TextMessageTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/TextMessageTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -27,10 +27,10 @@ import static org.assertj.core.api.Assertions.assertThat;
  * @author Shinobu Aoki
  * @author Juergen Hoeller
  */
-public class TextMessageTests {
+class TextMessageTests {
 
 	@Test
-	public void toStringWithAscii() {
+	void toStringWithAscii() {
 		String expected = "foo,bar";
 		TextMessage actual = new TextMessage(expected);
 		assertThat(actual.getPayload()).isEqualTo(expected);
@@ -38,7 +38,7 @@ public class TextMessageTests {
 	}
 
 	@Test
-	public void toStringWithMultibyteString() {
+	void toStringWithMultibyteString() {
 		String expected = "\u3042\u3044\u3046\u3048\u304a";
 		TextMessage actual = new TextMessage(expected);
 		assertThat(actual.getPayload()).isEqualTo(expected);
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/UndertowTestServer.java b/spring-websocket/src/test/java/org/springframework/web/socket/UndertowTestServer.java
index 50f618eb8e8..e26ce172bd2 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/UndertowTestServer.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/UndertowTestServer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -111,14 +111,14 @@ public class UndertowTestServer implements WebSocketTestServer {
 	}
 
 	@Override
-	public void start() throws Exception {
+	public void start() {
 		this.server.start();
 		Undertow.ListenerInfo info = this.server.getListenerInfo().get(0);
 		this.port = ((InetSocketAddress) info.getAddress()).getPort();
 	}
 
 	@Override
-	public void stop() throws Exception {
+	public void stop() {
 		this.server.stop();
 		this.port = 0;
 	}
@@ -143,7 +143,7 @@ public class UndertowTestServer implements WebSocketTestServer {
 		}
 
 		@Override
-		public InstanceHandle<Servlet> createInstance() throws InstantiationException {
+		public InstanceHandle<Servlet> createInstance() {
 			return new InstanceHandle<>() {
 				@Override
 				public Servlet getInstance() {
@@ -166,7 +166,7 @@ public class UndertowTestServer implements WebSocketTestServer {
 		}
 
 		@Override
-		public InstanceHandle<Filter> createInstance() throws InstantiationException {
+		public InstanceHandle<Filter> createInstance() {
 			return new InstanceHandle<>() {
 				@Override
 				public Filter getInstance() {
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/WebSocketExtensionTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/WebSocketExtensionTests.java
index 168c0a52193..2ab23568efb 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/WebSocketExtensionTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/WebSocketExtensionTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -29,10 +29,10 @@ import static org.assertj.core.api.Assertions.assertThat;
  * Test fixture for {@link WebSocketExtension}
  * @author Brian Clozel
  */
-public class WebSocketExtensionTests {
+class WebSocketExtensionTests {
 
 	@Test
-	public void parseHeaderSingle() {
+	void parseHeaderSingle() {
 		List<WebSocketExtension> extensions =
 				WebSocketExtension.parseExtensions("x-test-extension ; foo=bar ; bar=baz");
 
@@ -46,7 +46,7 @@ public class WebSocketExtensionTests {
 	}
 
 	@Test
-	public void parseHeaderMultiple() {
+	void parseHeaderMultiple() {
 		List<WebSocketExtension> extensions =
 				WebSocketExtension.parseExtensions("x-foo-extension, x-bar-extension");
 
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/WebSocketHandshakeTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/WebSocketHandshakeTests.java
index e380bcfb20e..74990097e18 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/WebSocketHandshakeTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/WebSocketHandshakeTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -101,7 +101,7 @@ class WebSocketHandshakeTests extends AbstractWebSocketIntegrationTests {
 		}
 
 		@Bean
-		public TestWebSocketHandler handler() {
+		TestWebSocketHandler handler() {
 			return new TestWebSocketHandler();
 		}
 
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/adapter/standard/ConvertingEncoderDecoderSupportTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/adapter/standard/ConvertingEncoderDecoderSupportTests.java
index 8cc8a6fa48a..04fa8def071 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/adapter/standard/ConvertingEncoderDecoderSupportTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/adapter/standard/ConvertingEncoderDecoderSupportTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -51,7 +51,7 @@ import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
  *
  * @author Phillip Webb
  */
-public class ConvertingEncoderDecoderSupportTests {
+class ConvertingEncoderDecoderSupportTests {
 
 	private static final String CONVERTED_TEXT = "_test";
 
@@ -64,12 +64,12 @@ public class ConvertingEncoderDecoderSupportTests {
 
 
 	@BeforeEach
-	public void setup() {
+	void setup() {
 		setup(Config.class);
 	}
 
 	@AfterEach
-	public void teardown() {
+	void teardown() {
 		ContextLoaderTestUtils.setCurrentWebApplicationContext(null);
 	}
 
@@ -82,12 +82,12 @@ public class ConvertingEncoderDecoderSupportTests {
 	}
 
 	@Test
-	public void encodeToText() throws Exception {
+	void encodeToText() throws Exception {
 		assertThat(new MyTextEncoder().encode(myType)).isEqualTo(CONVERTED_TEXT);
 	}
 
 	@Test
-	public void encodeToTextCannotConvert() throws Exception {
+	void encodeToTextCannotConvert() {
 		setup(NoConvertersConfig.class);
 		assertThatExceptionOfType(EncodeException.class).isThrownBy(() ->
 				new MyTextEncoder().encode(myType))
@@ -95,13 +95,13 @@ public class ConvertingEncoderDecoderSupportTests {
 	}
 
 	@Test
-	public void encodeToBinary() throws Exception {
+	void encodeToBinary() throws Exception {
 		assertThat(new MyBinaryEncoder().encode(myType).array())
 				.isEqualTo(CONVERTED_BYTES.array());
 	}
 
 	@Test
-	public void encodeToBinaryCannotConvert() throws Exception {
+	void encodeToBinaryCannotConvert() {
 		setup(NoConvertersConfig.class);
 		assertThatExceptionOfType(EncodeException.class).isThrownBy(() ->
 				new MyBinaryEncoder().encode(myType))
@@ -109,14 +109,14 @@ public class ConvertingEncoderDecoderSupportTests {
 	}
 
 	@Test
-	public void decodeFromText() throws Exception {
+	void decodeFromText() throws Exception {
 		Decoder.Text<MyType> decoder = new MyTextDecoder();
 		assertThat(decoder.willDecode(CONVERTED_TEXT)).isTrue();
 		assertThat(decoder.decode(CONVERTED_TEXT)).isEqualTo(myType);
 	}
 
 	@Test
-	public void decodeFromTextCannotConvert() throws Exception {
+	void decodeFromTextCannotConvert() {
 		setup(NoConvertersConfig.class);
 		Decoder.Text<MyType> decoder = new MyTextDecoder();
 		assertThat(decoder.willDecode(CONVERTED_TEXT)).isFalse();
@@ -126,14 +126,14 @@ public class ConvertingEncoderDecoderSupportTests {
 	}
 
 	@Test
-	public void decodeFromBinary() throws Exception {
+	void decodeFromBinary() throws Exception {
 		Decoder.Binary<MyType> decoder = new MyBinaryDecoder();
 		assertThat(decoder.willDecode(CONVERTED_BYTES)).isTrue();
 		assertThat(decoder.decode(CONVERTED_BYTES)).isEqualTo(myType);
 	}
 
 	@Test
-	public void decodeFromBinaryCannotConvert() throws Exception {
+	void decodeFromBinaryCannotConvert() {
 		setup(NoConvertersConfig.class);
 		Decoder.Binary<MyType> decoder = new MyBinaryDecoder();
 		assertThat(decoder.willDecode(CONVERTED_BYTES)).isFalse();
@@ -143,28 +143,28 @@ public class ConvertingEncoderDecoderSupportTests {
 	}
 
 	@Test
-	public void encodeAndDecodeText() throws Exception {
+	void encodeAndDecodeText() throws Exception {
 		MyTextEncoderDecoder encoderDecoder = new MyTextEncoderDecoder();
 		String encoded = encoderDecoder.encode(myType);
 		assertThat(encoderDecoder.decode(encoded)).isEqualTo(myType);
 	}
 
 	@Test
-	public void encodeAndDecodeBytes() throws Exception {
+	void encodeAndDecodeBytes() throws Exception {
 		MyBinaryEncoderDecoder encoderDecoder = new MyBinaryEncoderDecoder();
 		ByteBuffer encoded = encoderDecoder.encode(myType);
 		assertThat(encoderDecoder.decode(encoded)).isEqualTo(myType);
 	}
 
 	@Test
-	public void autowiresIntoEncoder() throws Exception {
+	void autowiresIntoEncoder() {
 		WithAutowire withAutowire = new WithAutowire();
 		withAutowire.init(null);
 		assertThat(withAutowire.config).isEqualTo(applicationContext.getBean(Config.class));
 	}
 
 	@Test
-	public void cannotFindApplicationContext() throws Exception {
+	void cannotFindApplicationContext() {
 		ContextLoaderTestUtils.setCurrentWebApplicationContext(null);
 		WithAutowire encoder = new WithAutowire();
 		encoder.init(null);
@@ -174,7 +174,7 @@ public class ConvertingEncoderDecoderSupportTests {
 	}
 
 	@Test
-	public void cannotFindConversionService() throws Exception {
+	void cannotFindConversionService() {
 		setup(NoConfig.class);
 		MyBinaryEncoder encoder = new MyBinaryEncoder();
 		encoder.init(null);
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/config/HandlersBeanDefinitionParserTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/config/HandlersBeanDefinitionParserTests.java
index 978d32f77e8..759893a5dd4 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/config/HandlersBeanDefinitionParserTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/config/HandlersBeanDefinitionParserTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -16,7 +16,6 @@
 
 package org.springframework.web.socket.config;
 
-import java.io.IOException;
 import java.io.InputStream;
 import java.time.Duration;
 import java.time.Instant;
@@ -70,13 +69,13 @@ import static org.assertj.core.api.Assertions.assertThat;
  * @author Brian Clozel
  * @author Rossen Stoyanchev
  */
-public class HandlersBeanDefinitionParserTests {
+class HandlersBeanDefinitionParserTests {
 
 	private final GenericWebApplicationContext appContext = new GenericWebApplicationContext();
 
 
 	@Test
-	public void webSocketHandlers() {
+	void webSocketHandlers() {
 		loadBeanDefinitions("websocket-config-handlers.xml");
 
 		Map<String, HandlerMapping> handlersMap = this.appContext.getBeansOfType(HandlerMapping.class);
@@ -118,7 +117,7 @@ public class HandlersBeanDefinitionParserTests {
 	}
 
 	@Test
-	public void webSocketHandlersAttributes() {
+	void webSocketHandlersAttributes() {
 		loadBeanDefinitions("websocket-config-handlers-attributes.xml");
 
 		HandlerMapping handlerMapping = this.appContext.getBean(HandlerMapping.class);
@@ -153,7 +152,7 @@ public class HandlersBeanDefinitionParserTests {
 	}
 
 	@Test
-	public void sockJs() {
+	void sockJs() {
 		loadBeanDefinitions("websocket-config-handlers-sockjs.xml");
 
 		SimpleUrlHandlerMapping handlerMapping = this.appContext.getBean(SimpleUrlHandlerMapping.class);
@@ -196,7 +195,7 @@ public class HandlersBeanDefinitionParserTests {
 	}
 
 	@Test
-	public void sockJsAttributes() {
+	void sockJsAttributes() {
 		loadBeanDefinitions("websocket-config-handlers-sockjs-attributes.xml");
 
 		SimpleUrlHandlerMapping handlerMapping = appContext.getBean(SimpleUrlHandlerMapping.class);
@@ -312,7 +311,7 @@ class BarTestInterceptor extends FooTestInterceptor {
 }
 
 
-@SuppressWarnings({ "unchecked", "rawtypes" })
+@SuppressWarnings("rawtypes")
 class TestTaskScheduler implements TaskScheduler {
 
 	@Override
@@ -355,12 +354,12 @@ class TestMessageCodec implements SockJsMessageCodec {
 	}
 
 	@Override
-	public String[] decode(String content) throws IOException {
+	public String[] decode(String content) {
 		return new String[0];
 	}
 
 	@Override
-	public String[] decodeInputStream(InputStream content) throws IOException {
+	public String[] decodeInputStream(InputStream content) {
 		return new String[0];
 	}
 }
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/config/MessageBrokerBeanDefinitionParserTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/config/MessageBrokerBeanDefinitionParserTests.java
index 59e431dd957..529f553c0de 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/config/MessageBrokerBeanDefinitionParserTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/config/MessageBrokerBeanDefinitionParserTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -101,13 +101,13 @@ import static org.assertj.core.api.InstanceOfAssertFactories.BOOLEAN;
  * @author Artem Bilan
  * @author Rossen Stoyanchev
  */
-public class MessageBrokerBeanDefinitionParserTests {
+class MessageBrokerBeanDefinitionParserTests {
 
 	private final GenericWebApplicationContext appContext = new GenericWebApplicationContext();
 
 
 	@Test
-	public void simpleBroker() throws Exception {
+	void simpleBroker() throws Exception {
 		loadBeanDefinitions("websocket-config-broker-simple.xml");
 
 		HandlerMapping hm = this.appContext.getBean(HandlerMapping.class);
@@ -231,7 +231,7 @@ public class MessageBrokerBeanDefinitionParserTests {
 	}
 
 	@Test
-	public void stompBrokerRelay() {
+	void stompBrokerRelay() {
 		loadBeanDefinitions("websocket-config-broker-relay.xml");
 
 		HandlerMapping hm = this.appContext.getBean(HandlerMapping.class);
@@ -319,7 +319,7 @@ public class MessageBrokerBeanDefinitionParserTests {
 	}
 
 	@Test
-	public void annotationMethodMessageHandler() {
+	void annotationMethodMessageHandler() {
 		loadBeanDefinitions("websocket-config-broker-simple.xml");
 
 		SimpAnnotationMethodMessageHandler annotationMethodMessageHandler =
@@ -355,7 +355,7 @@ public class MessageBrokerBeanDefinitionParserTests {
 	}
 
 	@Test
-	public void customChannels() {
+	void customChannels() {
 		loadBeanDefinitions("websocket-config-broker-customchannels.xml");
 
 		SimpAnnotationMethodMessageHandler annotationMethodMessageHandler =
@@ -393,7 +393,7 @@ public class MessageBrokerBeanDefinitionParserTests {
 	}
 
 	@Test
-	public void customArgumentAndReturnValueTypes() {
+	void customArgumentAndReturnValueTypes() {
 		loadBeanDefinitions("websocket-config-broker-custom-argument-and-return-value-types.xml");
 
 		SimpAnnotationMethodMessageHandler handler = this.appContext.getBean(SimpAnnotationMethodMessageHandler.class);
@@ -410,7 +410,7 @@ public class MessageBrokerBeanDefinitionParserTests {
 	}
 
 	@Test
-	public void messageConverters() {
+	void messageConverters() {
 		loadBeanDefinitions("websocket-config-broker-converters.xml");
 
 		CompositeMessageConverter compositeConverter = this.appContext.getBean(CompositeMessageConverter.class);
@@ -421,7 +421,7 @@ public class MessageBrokerBeanDefinitionParserTests {
 	}
 
 	@Test
-	public void messageConvertersDefaultsOff() {
+	void messageConvertersDefaultsOff() {
 		loadBeanDefinitions("websocket-config-broker-converters-defaults-off.xml");
 
 		CompositeMessageConverter compositeConverter = this.appContext.getBean(CompositeMessageConverter.class);
@@ -478,7 +478,7 @@ class CustomArgumentResolver implements HandlerMethodArgumentResolver {
 	}
 
 	@Override
-	public Object resolveArgument(MethodParameter parameter, Message<?> message) throws Exception {
+	public Object resolveArgument(MethodParameter parameter, Message<?> message) {
 		return null;
 	}
 }
@@ -492,7 +492,7 @@ class CustomReturnValueHandler implements HandlerMethodReturnValueHandler {
 	}
 
 	@Override
-	public void handleReturnValue(Object returnValue, MethodParameter returnType, Message<?> message) throws Exception {
+	public void handleReturnValue(Object returnValue, MethodParameter returnType, Message<?> message) {
 	}
 }
 
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebMvcStompEndpointRegistryTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebMvcStompEndpointRegistryTests.java
index 88793372b39..09579c98e6f 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebMvcStompEndpointRegistryTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebMvcStompEndpointRegistryTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -39,7 +39,7 @@ import static org.mockito.Mockito.mock;
  *
  * @author Rossen Stoyanchev
  */
-public class WebMvcStompEndpointRegistryTests {
+class WebMvcStompEndpointRegistryTests {
 
 	private WebMvcStompEndpointRegistry endpointRegistry;
 
@@ -47,7 +47,7 @@ public class WebMvcStompEndpointRegistryTests {
 
 
 	@BeforeEach
-	public void setup() {
+	void setup() {
 		SubscribableChannel inChannel = mock();
 		SubscribableChannel outChannel = mock();
 		this.webSocketHandler = new SubProtocolWebSocketHandler(inChannel, outChannel);
@@ -59,7 +59,7 @@ public class WebMvcStompEndpointRegistryTests {
 
 
 	@Test
-	public void stompProtocolHandler() {
+	void stompProtocolHandler() {
 		this.endpointRegistry.addEndpoint("/stomp");
 
 		Map<String, SubProtocolHandler> protocolHandlers = webSocketHandler.getProtocolHandlerMap();
@@ -70,7 +70,7 @@ public class WebMvcStompEndpointRegistryTests {
 	}
 
 	@Test
-	public void handlerMapping() {
+	void handlerMapping() {
 		SimpleUrlHandlerMapping hm = (SimpleUrlHandlerMapping) this.endpointRegistry.getHandlerMapping();
 		assertThat(hm.getUrlMap()).isEmpty();
 
@@ -90,7 +90,7 @@ public class WebMvcStompEndpointRegistryTests {
 	}
 
 	@Test
-	public void errorHandler() throws Exception {
+	void errorHandler() {
 		StompSubProtocolErrorHandler errorHandler = mock();
 		this.endpointRegistry.setErrorHandler(errorHandler);
 		this.endpointRegistry.addEndpoint("/stompOverWebSocket");
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebMvcStompWebSocketEndpointRegistrationTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebMvcStompWebSocketEndpointRegistrationTests.java
index faa2f53eba3..569595014a0 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebMvcStompWebSocketEndpointRegistrationTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebMvcStompWebSocketEndpointRegistrationTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -185,8 +185,8 @@ class WebMvcStompWebSocketEndpointRegistrationTests {
 		assertThat(requestHandler.getWebSocketHandler()).isNotNull();
 		assertThat(requestHandler.getHandshakeHandler()).isSameAs(handshakeHandler);
 		assertThat(requestHandler.getHandshakeInterceptors()).hasSize(2);
-		assertThat(requestHandler.getHandshakeInterceptors()).element(0).isEqualTo(interceptor);
-		assertThat(requestHandler.getHandshakeInterceptors().get(1).getClass()).isEqualTo(OriginHandshakeInterceptor.class);
+		assertThat(requestHandler.getHandshakeInterceptors().get(0)).isEqualTo(interceptor);
+		assertThat(requestHandler.getHandshakeInterceptors().get(1)).isInstanceOf(OriginHandshakeInterceptor.class);
 	}
 
 	@Test
@@ -209,8 +209,8 @@ class WebMvcStompWebSocketEndpointRegistrationTests {
 		assertThat(requestHandler.getWebSocketHandler()).isNotNull();
 		assertThat(requestHandler.getHandshakeHandler()).isSameAs(handshakeHandler);
 		assertThat(requestHandler.getHandshakeInterceptors()).hasSize(2);
-		assertThat(requestHandler.getHandshakeInterceptors()).element(0).isEqualTo(interceptor);
-		assertThat(requestHandler.getHandshakeInterceptors().get(1).getClass()).isEqualTo(OriginHandshakeInterceptor.class);
+		assertThat(requestHandler.getHandshakeInterceptors().get(0)).isEqualTo(interceptor);
+		assertThat(requestHandler.getHandshakeInterceptors().get(1)).isInstanceOf(OriginHandshakeInterceptor.class);
 	}
 
 	@Test
@@ -239,8 +239,8 @@ class WebMvcStompWebSocketEndpointRegistrationTests {
 		WebSocketTransportHandler transportHandler = (WebSocketTransportHandler) handlers.get(TransportType.WEBSOCKET);
 		assertThat(transportHandler.getHandshakeHandler()).isSameAs(handshakeHandler);
 		assertThat(sockJsService.getHandshakeInterceptors()).hasSize(2);
-		assertThat(sockJsService.getHandshakeInterceptors()).element(0).isEqualTo(interceptor);
-		assertThat(sockJsService.getHandshakeInterceptors().get(1).getClass()).isEqualTo(OriginHandshakeInterceptor.class);
+		assertThat(sockJsService.getHandshakeInterceptors().get(0)).isEqualTo(interceptor);
+		assertThat(sockJsService.getHandshakeInterceptors().get(1)).isInstanceOf(OriginHandshakeInterceptor.class);
 	}
 
 	@Test
@@ -271,8 +271,8 @@ class WebMvcStompWebSocketEndpointRegistrationTests {
 		WebSocketTransportHandler transportHandler = (WebSocketTransportHandler) handlers.get(TransportType.WEBSOCKET);
 		assertThat(transportHandler.getHandshakeHandler()).isSameAs(handshakeHandler);
 		assertThat(sockJsService.getHandshakeInterceptors()).hasSize(2);
-		assertThat(sockJsService.getHandshakeInterceptors()).element(0).isEqualTo(interceptor);
-		assertThat(sockJsService.getHandshakeInterceptors().get(1).getClass()).isEqualTo(OriginHandshakeInterceptor.class);
+		assertThat(sockJsService.getHandshakeInterceptors().get(0)).isEqualTo(interceptor);
+		assertThat(sockJsService.getHandshakeInterceptors().get(1)).isInstanceOf(OriginHandshakeInterceptor.class);
 		assertThat(sockJsService.getAllowedOrigins()).contains(origin);
 	}
 
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebSocketConfigurationTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebSocketConfigurationTests.java
index 951f6e213ca..d9fd68e2d30 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebSocketConfigurationTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebSocketConfigurationTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -95,7 +95,7 @@ class WebSocketConfigurationTests extends AbstractWebSocketIntegrationTests {
 		}
 
 		@Bean
-		public TestHandler serverHandler() {
+		TestHandler serverHandler() {
 			return new TestHandler();
 		}
 	}
@@ -103,10 +103,10 @@ class WebSocketConfigurationTests extends AbstractWebSocketIntegrationTests {
 
 	private static class TestHandler extends AbstractWebSocketHandler {
 
-		private CountDownLatch connectLatch = new CountDownLatch(1);
+		private final CountDownLatch connectLatch = new CountDownLatch(1);
 
 		@Override
-		public void afterConnectionEstablished(WebSocketSession session) throws Exception {
+		public void afterConnectionEstablished(WebSocketSession session) {
 			this.connectLatch.countDown();
 		}
 	}
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebSocketHandlerRegistrationTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebSocketHandlerRegistrationTests.java
index 171b8f90db8..1b96b355cf1 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebSocketHandlerRegistrationTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/config/annotation/WebSocketHandlerRegistrationTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -42,7 +42,7 @@ import static org.mockito.Mockito.mock;
  *
  * @author Rossen Stoyanchev
  */
-public class WebSocketHandlerRegistrationTests {
+class WebSocketHandlerRegistrationTests {
 
 	private TestWebSocketHandlerRegistration registration = new TestWebSocketHandlerRegistration();
 
@@ -50,7 +50,7 @@ public class WebSocketHandlerRegistrationTests {
 
 
 	@Test
-	public void minimal() {
+	void minimal() {
 		WebSocketHandler handler = new TextWebSocketHandler();
 		this.registration.addHandler(handler, "/foo", "/bar");
 
@@ -73,7 +73,7 @@ public class WebSocketHandlerRegistrationTests {
 	}
 
 	@Test
-	public void interceptors() {
+	void interceptors() {
 		WebSocketHandler handler = new TextWebSocketHandler();
 		HttpSessionHandshakeInterceptor interceptor = new HttpSessionHandshakeInterceptor();
 
@@ -92,7 +92,7 @@ public class WebSocketHandlerRegistrationTests {
 	}
 
 	@Test
-	public void emptyAllowedOrigin() {
+	void emptyAllowedOrigin() {
 		WebSocketHandler handler = new TextWebSocketHandler();
 		HttpSessionHandshakeInterceptor interceptor = new HttpSessionHandshakeInterceptor();
 
@@ -111,7 +111,7 @@ public class WebSocketHandlerRegistrationTests {
 	}
 
 	@Test
-	public void interceptorsWithAllowedOrigins() {
+	void interceptorsWithAllowedOrigins() {
 		WebSocketHandler handler = new TextWebSocketHandler();
 		HttpSessionHandshakeInterceptor interceptor = new HttpSessionHandshakeInterceptor();
 
@@ -136,7 +136,7 @@ public class WebSocketHandlerRegistrationTests {
 	}
 
 	@Test
-	public void interceptorsPassedToSockJsRegistration() {
+	void interceptorsPassedToSockJsRegistration() {
 		WebSocketHandler handler = new TextWebSocketHandler();
 		HttpSessionHandshakeInterceptor interceptor = new HttpSessionHandshakeInterceptor();
 
@@ -157,7 +157,7 @@ public class WebSocketHandlerRegistrationTests {
 		assertThat(mapping.sockJsService).isNotNull();
 		assertThat(mapping.sockJsService.getAllowedOrigins()).contains("https://mydomain1.example");
 		List<HandshakeInterceptor> interceptors = mapping.sockJsService.getHandshakeInterceptors();
-		assertThat(interceptors).element(0).isEqualTo(interceptor);
+		assertThat(interceptors.get(0)).isEqualTo(interceptor);
 
 		OriginHandshakeInterceptor originInterceptor = (OriginHandshakeInterceptor) interceptors.get(1);
 		assertThat(originInterceptor.getAllowedOrigins()).containsExactly("https://mydomain1.example");
@@ -165,7 +165,7 @@ public class WebSocketHandlerRegistrationTests {
 	}
 
 	@Test
-	public void handshakeHandler() {
+	void handshakeHandler() {
 		WebSocketHandler handler = new TextWebSocketHandler();
 		HandshakeHandler handshakeHandler = new DefaultHandshakeHandler();
 
@@ -181,7 +181,7 @@ public class WebSocketHandlerRegistrationTests {
 	}
 
 	@Test
-	public void handshakeHandlerPassedToSockJsRegistration() {
+	void handshakeHandlerPassedToSockJsRegistration() {
 		WebSocketHandler handler = new TextWebSocketHandler();
 		HandshakeHandler handshakeHandler = new DefaultHandshakeHandler();
 
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/handler/BeanCreatingHandlerProviderTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/handler/BeanCreatingHandlerProviderTests.java
index 27f79bfb3f1..65a098c6f5c 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/handler/BeanCreatingHandlerProviderTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/handler/BeanCreatingHandlerProviderTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -33,11 +33,11 @@ import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
  *
  * @author Rossen Stoyanchev
  */
-public class BeanCreatingHandlerProviderTests {
+class BeanCreatingHandlerProviderTests {
 
 
 	@Test
-	public void getHandlerSimpleInstantiation() {
+	void getHandlerSimpleInstantiation() {
 
 		BeanCreatingHandlerProvider<SimpleEchoHandler> provider =
 				new BeanCreatingHandlerProvider<>(SimpleEchoHandler.class);
@@ -46,9 +46,8 @@ public class BeanCreatingHandlerProviderTests {
 	}
 
 	@Test
-	public void getHandlerWithBeanFactory() {
+	void getHandlerWithBeanFactory() {
 
-		@SuppressWarnings("resource")
 		ConfigurableApplicationContext context = new AnnotationConfigApplicationContext(Config.class);
 
 		BeanCreatingHandlerProvider<EchoHandler> provider =
@@ -59,7 +58,7 @@ public class BeanCreatingHandlerProviderTests {
 	}
 
 	@Test
-	public void getHandlerNoBeanFactory() {
+	void getHandlerNoBeanFactory() {
 
 		BeanCreatingHandlerProvider<EchoHandler> provider =
 				new BeanCreatingHandlerProvider<>(EchoHandler.class);
@@ -73,7 +72,7 @@ public class BeanCreatingHandlerProviderTests {
 	static class Config {
 
 		@Bean
-		public EchoService echoService() {
+		EchoService echoService() {
 			return new EchoService();
 		}
 	}
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/handler/ConcurrentWebSocketSessionDecoratorTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/handler/ConcurrentWebSocketSessionDecoratorTests.java
index 00b49020b44..15074872743 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/handler/ConcurrentWebSocketSessionDecoratorTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/handler/ConcurrentWebSocketSessionDecoratorTests.java
@@ -36,11 +36,10 @@ import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
  *
  * @author Rossen Stoyanchev
  */
-@SuppressWarnings("resource")
-public class ConcurrentWebSocketSessionDecoratorTests {
+class ConcurrentWebSocketSessionDecoratorTests {
 
 	@Test
-	public void send() throws IOException {
+	void send() throws IOException {
 
 		TestWebSocketSession session = new TestWebSocketSession();
 		session.setOpen(true);
@@ -51,8 +50,7 @@ public class ConcurrentWebSocketSessionDecoratorTests {
 		TextMessage textMessage = new TextMessage("payload");
 		decorator.sendMessage(textMessage);
 
-		assertThat(session.getSentMessages()).hasSize(1);
-		assertThat(session.getSentMessages()).element(0).isEqualTo(textMessage);
+		assertThat(session.getSentMessages()).containsExactly(textMessage);
 
 		assertThat(decorator.getBufferSize()).isEqualTo(0);
 		assertThat(decorator.getTimeSinceSendStarted()).isEqualTo(0);
@@ -60,7 +58,7 @@ public class ConcurrentWebSocketSessionDecoratorTests {
 	}
 
 	@Test
-	public void sendAfterBlockedSend() throws IOException, InterruptedException {
+	void sendAfterBlockedSend() throws IOException, InterruptedException {
 
 		BlockingWebSocketSession session = new BlockingWebSocketSession();
 		session.setOpen(true);
@@ -84,7 +82,7 @@ public class ConcurrentWebSocketSessionDecoratorTests {
 	}
 
 	@Test
-	public void sendTimeLimitExceeded() throws InterruptedException {
+	void sendTimeLimitExceeded() throws InterruptedException {
 
 		BlockingWebSocketSession session = new BlockingWebSocketSession();
 		session.setId("123");
@@ -95,7 +93,7 @@ public class ConcurrentWebSocketSessionDecoratorTests {
 
 		sendBlockingMessage(decorator);
 
-		// Exceed send time..
+		// Exceed send time
 		Thread.sleep(200);
 
 		TextMessage payload = new TextMessage("payload");
@@ -106,7 +104,7 @@ public class ConcurrentWebSocketSessionDecoratorTests {
 	}
 
 	@Test
-	public void sendBufferSizeExceeded() throws IOException, InterruptedException {
+	void sendBufferSizeExceeded() throws IOException, InterruptedException {
 
 		BlockingWebSocketSession session = new BlockingWebSocketSession();
 		session.setId("123");
@@ -154,7 +152,7 @@ public class ConcurrentWebSocketSessionDecoratorTests {
 	}
 
 	@Test
-	public void closeStatusNormal() throws Exception {
+	void closeStatusNormal() throws Exception {
 
 		BlockingWebSocketSession session = new BlockingWebSocketSession();
 		session.setOpen(true);
@@ -168,7 +166,7 @@ public class ConcurrentWebSocketSessionDecoratorTests {
 	}
 
 	@Test
-	public void closeStatusChangesToSessionNotReliable() throws Exception {
+	void closeStatusChangesToSessionNotReliable() throws Exception {
 
 		BlockingWebSocketSession session = new BlockingWebSocketSession();
 		session.setId("123");
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/handler/PerConnectionWebSocketHandlerTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/handler/PerConnectionWebSocketHandlerTests.java
index 72c4357fa1b..b513edbf8be 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/handler/PerConnectionWebSocketHandlerTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/handler/PerConnectionWebSocketHandlerTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -30,13 +30,12 @@ import static org.assertj.core.api.Assertions.assertThat;
  *
  * @author Rossen Stoyanchev
  */
-public class PerConnectionWebSocketHandlerTests {
+class PerConnectionWebSocketHandlerTests {
 
 
 	@Test
-	public void afterConnectionEstablished() throws Exception {
+	void afterConnectionEstablished() throws Exception {
 
-		@SuppressWarnings("resource")
 		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 		context.refresh();
 
@@ -69,7 +68,7 @@ public class PerConnectionWebSocketHandlerTests {
 		}
 
 		@Override
-		public void destroy() throws Exception {
+		public void destroy() {
 			destroyCount++;
 		}
 
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/handler/WebSocketHandlerDecoratorTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/handler/WebSocketHandlerDecoratorTests.java
index 5f19bc11d5f..bbe25e55e0d 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/handler/WebSocketHandlerDecoratorTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/handler/WebSocketHandlerDecoratorTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -25,10 +25,10 @@ import static org.assertj.core.api.Assertions.assertThat;
  *
  * @author Rossen Stoyanchev
  */
-public class WebSocketHandlerDecoratorTests {
+class WebSocketHandlerDecoratorTests {
 
 	@Test
-	public void getLastHandler() {
+	void getLastHandler() {
 		AbstractWebSocketHandler h1 = new AbstractWebSocketHandler() {
 		};
 		WebSocketHandlerDecorator h2 = new WebSocketHandlerDecorator(h1);
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/handler/WebSocketHttpHeadersTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/handler/WebSocketHttpHeadersTests.java
index c44dbc2225a..cf4d7ff571e 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/handler/WebSocketHttpHeadersTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/handler/WebSocketHttpHeadersTests.java
@@ -33,17 +33,17 @@ import static org.assertj.core.api.Assertions.assertThat;
  *
  * @author Rossen Stoyanchev
  */
-public class WebSocketHttpHeadersTests {
+class WebSocketHttpHeadersTests {
 
 	private WebSocketHttpHeaders headers;
 
 	@BeforeEach
-	public void setUp() {
+	void setUp() {
 		headers = new WebSocketHttpHeaders();
 	}
 
 	@Test
-	public void parseWebSocketExtensions() {
+	void parseWebSocketExtensions() {
 		List<String> extensions = new ArrayList<>();
 		extensions.add("x-foo-extension, x-bar-extension");
 		extensions.add("x-test-extension");
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/DefaultSimpUserRegistryTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/DefaultSimpUserRegistryTests.java
index decca24a417..8b22ba1adec 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/DefaultSimpUserRegistryTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/DefaultSimpUserRegistryTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -41,10 +41,10 @@ import static org.assertj.core.api.Assertions.assertThat;
  * @author Rossen Stoyanchev
  * @since 4.0
  */
-public class DefaultSimpUserRegistryTests {
+class DefaultSimpUserRegistryTests {
 
 	@Test
-	public void addOneSessionId() {
+	void addOneSessionId() {
 		TestPrincipal user = new TestPrincipal("joe");
 		Message<byte[]> message = createMessage(SimpMessageType.CONNECT_ACK, "123");
 		SessionConnectedEvent event = new SessionConnectedEvent(this, message, user);
@@ -61,7 +61,7 @@ public class DefaultSimpUserRegistryTests {
 	}
 
 	@Test
-	public void addMultipleSessionIds() {
+	void addMultipleSessionIds() {
 		DefaultSimpUserRegistry registry = new DefaultSimpUserRegistry();
 
 		TestPrincipal user = new TestPrincipal("joe");
@@ -88,7 +88,7 @@ public class DefaultSimpUserRegistryTests {
 	}
 
 	@Test
-	public void removeSessionIds() {
+	void removeSessionIds() {
 		DefaultSimpUserRegistry registry = new DefaultSimpUserRegistry();
 
 		TestPrincipal user = new TestPrincipal("joe");
@@ -122,7 +122,7 @@ public class DefaultSimpUserRegistryTests {
 	}
 
 	@Test
-	public void findSubscriptions() throws Exception {
+	void findSubscriptions() {
 		DefaultSimpUserRegistry registry = new DefaultSimpUserRegistry();
 
 		TestPrincipal user = new TestPrincipal("joe");
@@ -154,7 +154,7 @@ public class DefaultSimpUserRegistryTests {
 	}
 
 	@Test
-	public void nullSessionId() throws Exception {
+	void nullSessionId() {
 		DefaultSimpUserRegistry registry = new DefaultSimpUserRegistry();
 
 		TestPrincipal user = new TestPrincipal("joe");
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/OrderedMessageSendingIntegrationTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/OrderedMessageSendingIntegrationTests.java
index 735619cff20..a405fc0351f 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/OrderedMessageSendingIntegrationTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/OrderedMessageSendingIntegrationTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -70,7 +70,7 @@ import static org.assertj.core.api.Assertions.assertThat;
  *
  * @author Rossen Stoyanchev
  */
-public class OrderedMessageSendingIntegrationTests {
+class OrderedMessageSendingIntegrationTests {
 
 	private static final Log logger = LogFactory.getLog(OrderedMessageSendingIntegrationTests.class);
 
@@ -88,7 +88,7 @@ public class OrderedMessageSendingIntegrationTests {
 
 
 	@BeforeEach
-	public void setup() {
+	void setup() {
 		this.blockingSession = new BlockingWebSocketSession();
 		this.blockingSession.setId("1");
 		this.blockingSession.setOpen(true);
@@ -105,7 +105,7 @@ public class OrderedMessageSendingIntegrationTests {
 	}
 
 	@AfterEach
-	public void tearDown() {
+	void tearDown() {
 		this.executor.shutdown();
 	}
 
@@ -157,7 +157,7 @@ public class OrderedMessageSendingIntegrationTests {
 		// Send one to block
 		this.orderedClientOutChannel.send(createMessage(0));
 
-		// Exceed send time..
+		// Exceed send time
 		Thread.sleep(200);
 
 		CountDownLatch messageLatch = new CountDownLatch(1);
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/StompSubProtocolErrorHandlerTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/StompSubProtocolErrorHandlerTests.java
index 8e9e4ac4bbe..052aed5670b 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/StompSubProtocolErrorHandlerTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/StompSubProtocolErrorHandlerTests.java
@@ -33,19 +33,19 @@ import static org.assertj.core.api.Assertions.assertThat;
  *
  * @author Rossen Stoyanchev
  */
-public class StompSubProtocolErrorHandlerTests {
+class StompSubProtocolErrorHandlerTests {
 
 	private StompSubProtocolErrorHandler handler;
 
 
 	@BeforeEach
-	public void setUp() throws Exception {
+	void setUp() {
 		this.handler = new StompSubProtocolErrorHandler();
 	}
 
 
 	@Test
-	public void handleClientMessageProcessingError() throws Exception {
+	void handleClientMessageProcessingError() {
 
 		Exception ex = new Exception("fake exception");
 		Message<byte[]> actual = this.handler.handleClientMessageProcessingError(null, ex);
@@ -59,7 +59,7 @@ public class StompSubProtocolErrorHandlerTests {
 	}
 
 	@Test
-	public void handleClientMessageProcessingErrorWithReceipt() throws Exception {
+	void handleClientMessageProcessingErrorWithReceipt() {
 
 		String receiptId = "123";
 		StompHeaderAccessor clientHeaderAccessor = StompHeaderAccessor.create(StompCommand.SEND);
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/SubProtocolWebSocketHandlerTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/SubProtocolWebSocketHandlerTests.java
index 0abf386f51f..c1ef8b828d3 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/SubProtocolWebSocketHandlerTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/SubProtocolWebSocketHandlerTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -68,7 +68,7 @@ public class SubProtocolWebSocketHandlerTests {
 
 
 	@BeforeEach
-	public void setup() {
+	void setup() {
 		this.webSocketHandler = new SubProtocolWebSocketHandler(this.inClientChannel, this.outClientChannel);
 		given(stompHandler.getSupportedProtocols()).willReturn(Arrays.asList("v10.stomp", "v11.stomp", "v12.stomp"));
 		given(mqttHandler.getSupportedProtocols()).willReturn(List.of("MQTT"));
@@ -79,7 +79,7 @@ public class SubProtocolWebSocketHandlerTests {
 
 
 	@Test
-	public void subProtocolMatch() throws Exception {
+	void subProtocolMatch() throws Exception {
 		this.webSocketHandler.setProtocolHandlers(Arrays.asList(stompHandler, mqttHandler));
 		this.session.setAcceptedProtocol("v12.sToMp");
 		this.webSocketHandler.afterConnectionEstablished(session);
@@ -90,7 +90,7 @@ public class SubProtocolWebSocketHandlerTests {
 	}
 
 	@Test
-	public void subProtocolDefaultHandlerOnly() throws Exception {
+	void subProtocolDefaultHandlerOnly() throws Exception {
 		this.webSocketHandler.setDefaultProtocolHandler(stompHandler);
 		this.session.setAcceptedProtocol("v12.sToMp");
 		this.webSocketHandler.afterConnectionEstablished(session);
@@ -100,7 +100,7 @@ public class SubProtocolWebSocketHandlerTests {
 	}
 
 	@Test
-	public void subProtocolNoMatch() throws Exception {
+	void subProtocolNoMatch() {
 		this.webSocketHandler.setDefaultProtocolHandler(defaultHandler);
 		this.webSocketHandler.setProtocolHandlers(Arrays.asList(stompHandler, mqttHandler));
 		this.session.setAcceptedProtocol("wamp");
@@ -110,7 +110,7 @@ public class SubProtocolWebSocketHandlerTests {
 	}
 
 	@Test
-	public void nullSubProtocol() throws Exception {
+	void nullSubProtocol() throws Exception {
 		this.webSocketHandler.setDefaultProtocolHandler(defaultHandler);
 		this.webSocketHandler.afterConnectionEstablished(session);
 
@@ -121,7 +121,7 @@ public class SubProtocolWebSocketHandlerTests {
 	}
 
 	@Test
-	public void emptySubProtocol() throws Exception {
+	void emptySubProtocol() throws Exception {
 		this.session.setAcceptedProtocol("");
 		this.webSocketHandler.setDefaultProtocolHandler(this.defaultHandler);
 		this.webSocketHandler.afterConnectionEstablished(session);
@@ -133,7 +133,7 @@ public class SubProtocolWebSocketHandlerTests {
 	}
 
 	@Test
-	public void noSubProtocolOneHandler() throws Exception {
+	void noSubProtocolOneHandler() throws Exception {
 		this.webSocketHandler.setProtocolHandlers(List.of(stompHandler));
 		this.webSocketHandler.afterConnectionEstablished(session);
 
@@ -142,14 +142,14 @@ public class SubProtocolWebSocketHandlerTests {
 	}
 
 	@Test
-	public void noSubProtocolTwoHandlers() throws Exception {
+	void noSubProtocolTwoHandlers() {
 		this.webSocketHandler.setProtocolHandlers(Arrays.asList(stompHandler, mqttHandler));
 		assertThatIllegalStateException().isThrownBy(() ->
 				this.webSocketHandler.afterConnectionEstablished(session));
 	}
 
 	@Test
-	public void noSubProtocolNoDefaultHandler() throws Exception {
+	void noSubProtocolNoDefaultHandler() {
 		this.webSocketHandler.setProtocolHandlers(Arrays.asList(stompHandler, mqttHandler));
 		assertThatIllegalStateException().isThrownBy(() ->
 				this.webSocketHandler.afterConnectionEstablished(session));
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketAnnotationMethodMessageHandlerTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketAnnotationMethodMessageHandlerTests.java
index 9494b831d30..1c819836241 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketAnnotationMethodMessageHandlerTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketAnnotationMethodMessageHandlerTests.java
@@ -42,7 +42,7 @@ import static org.mockito.Mockito.mock;
  *
  * @author Rossen Stoyanchev
  */
-public class WebSocketAnnotationMethodMessageHandlerTests {
+class WebSocketAnnotationMethodMessageHandlerTests {
 
 	private TestWebSocketAnnotationMethodMessageHandler messageHandler;
 
@@ -50,7 +50,7 @@ public class WebSocketAnnotationMethodMessageHandlerTests {
 
 
 	@BeforeEach
-	public void setUp() throws Exception {
+	void setUp() {
 		this.applicationContext = new StaticApplicationContext();
 		this.applicationContext.registerSingleton("controller", TestController.class);
 		this.applicationContext.registerSingleton("controllerAdvice", TestControllerAdvice.class);
@@ -65,7 +65,7 @@ public class WebSocketAnnotationMethodMessageHandlerTests {
 	}
 
 	@Test
-	public void globalException() throws Exception {
+	void globalException() {
 		SimpMessageHeaderAccessor headers = SimpMessageHeaderAccessor.create();
 		headers.setSessionId("session1");
 		headers.setSessionAttributes(new ConcurrentHashMap<>());
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketStompClientIntegrationTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketStompClientIntegrationTests.java
index c4203bc96ca..f8b7b538661 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketStompClientIntegrationTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketStompClientIntegrationTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -86,7 +86,7 @@ class WebSocketStompClientIntegrationTests {
 	}
 
 	@AfterEach
-	void tearDown() throws Exception {
+	void tearDown() {
 		try {
 			this.server.undeployConfig();
 		}
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketStompClientTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketStompClientTests.java
index 8753ecf15db..019bed80396 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketStompClientTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/messaging/WebSocketStompClientTests.java
@@ -86,7 +86,7 @@ class WebSocketStompClientTests {
 
 
 	@BeforeEach
-	void setUp() throws Exception {
+	void setUp() {
 		WebSocketClient webSocketClient = mock();
 		this.stompClient = new TestWebSocketStompClient(webSocketClient);
 		this.stompClient.setTaskScheduler(this.taskScheduler);
@@ -100,7 +100,7 @@ class WebSocketStompClientTests {
 
 
 	@Test
-	void webSocketHandshakeFailure() throws Exception {
+	void webSocketHandshakeFailure() {
 		connect();
 
 		IllegalStateException handshakeFailure = new IllegalStateException("simulated exception");
@@ -229,7 +229,7 @@ class WebSocketStompClientTests {
 	}
 
 	@Test
-	void heartbeatDefaultValue() throws Exception {
+	void heartbeatDefaultValue() {
 		WebSocketStompClient stompClient = new WebSocketStompClient(mock());
 		assertThat(stompClient.getDefaultHeartbeat()).isEqualTo(new long[] {0, 0});
 
@@ -238,7 +238,7 @@ class WebSocketStompClientTests {
 	}
 
 	@Test
-	void heartbeatDefaultValueWithScheduler() throws Exception {
+	void heartbeatDefaultValueWithScheduler() {
 		WebSocketStompClient stompClient = new WebSocketStompClient(mock());
 		stompClient.setTaskScheduler(mock());
 		assertThat(stompClient.getDefaultHeartbeat()).isEqualTo(new long[] {10000, 10000});
@@ -248,7 +248,7 @@ class WebSocketStompClientTests {
 	}
 
 	@Test
-	void heartbeatDefaultValueSetWithoutScheduler() throws Exception {
+	void heartbeatDefaultValueSetWithoutScheduler() {
 		WebSocketStompClient stompClient = new WebSocketStompClient(mock());
 		stompClient.setDefaultHeartbeat(new long[] {5, 5});
 		assertThatIllegalStateException().isThrownBy(() ->
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/server/DefaultHandshakeHandlerTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/server/DefaultHandshakeHandlerTests.java
index 6ea57d7905c..4a8cdc08227 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/server/DefaultHandshakeHandlerTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/server/DefaultHandshakeHandlerTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -41,7 +41,7 @@ import static org.mockito.Mockito.verify;
  *
  * @author Rossen Stoyanchev
  */
-public class DefaultHandshakeHandlerTests extends AbstractHttpRequestTests {
+class DefaultHandshakeHandlerTests extends AbstractHttpRequestTests {
 
 	private RequestUpgradeStrategy upgradeStrategy = mock();
 
@@ -49,7 +49,7 @@ public class DefaultHandshakeHandlerTests extends AbstractHttpRequestTests {
 
 
 	@Test
-	public void supportedSubProtocols() {
+	void supportedSubProtocols() {
 		this.handshakeHandler.setSupportedProtocols("stomp", "mqtt");
 		given(this.upgradeStrategy.getSupportedVersions()).willReturn(new String[] {"13"});
 
@@ -65,7 +65,7 @@ public class DefaultHandshakeHandlerTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void supportedExtensions() {
+	void supportedExtensions() {
 		WebSocketExtension extension1 = new WebSocketExtension("ext1");
 		WebSocketExtension extension2 = new WebSocketExtension("ext2");
 
@@ -84,7 +84,7 @@ public class DefaultHandshakeHandlerTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void subProtocolCapableHandler() {
+	void subProtocolCapableHandler() {
 		given(this.upgradeStrategy.getSupportedVersions()).willReturn(new String[] {"13"});
 
 		this.servletRequest.setMethod("GET");
@@ -99,7 +99,7 @@ public class DefaultHandshakeHandlerTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void subProtocolCapableHandlerNoMatch() {
+	void subProtocolCapableHandlerNoMatch() {
 		given(this.upgradeStrategy.getSupportedVersions()).willReturn(new String[] {"13"});
 
 		this.servletRequest.setMethod("GET");
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/server/standard/ServerEndpointRegistrationTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/server/standard/ServerEndpointRegistrationTests.java
index 7e32bc93adc..4553f54cc4d 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/server/standard/ServerEndpointRegistrationTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/server/standard/ServerEndpointRegistrationTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -34,13 +34,12 @@ import static org.assertj.core.api.Assertions.assertThat;
  *
  * @author Rossen Stoyanchev
  */
-public class ServerEndpointRegistrationTests {
+class ServerEndpointRegistrationTests {
 
 
 	@Test
-	public void endpointPerConnection() throws Exception {
+	void endpointPerConnection() throws Exception {
 
-		@SuppressWarnings("resource")
 		ConfigurableApplicationContext context = new AnnotationConfigApplicationContext(Config.class);
 
 		ServerEndpointRegistration registration = new ServerEndpointRegistration("/path", EchoEndpoint.class);
@@ -52,7 +51,7 @@ public class ServerEndpointRegistrationTests {
 	}
 
 	@Test
-	public void endpointSingleton() throws Exception {
+	void endpointSingleton() throws Exception {
 
 		EchoEndpoint endpoint = new EchoEndpoint(new EchoService());
 		ServerEndpointRegistration registration = new ServerEndpointRegistration("/path", endpoint);
@@ -67,7 +66,7 @@ public class ServerEndpointRegistrationTests {
 	static class Config {
 
 		@Bean
-		public EchoService echoService() {
+		EchoService echoService() {
 			return new EchoService();
 		}
 	}
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/server/standard/SpringConfiguratorTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/server/standard/SpringConfiguratorTests.java
index 156d3ec48fb..54978a409b4 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/server/standard/SpringConfiguratorTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/server/standard/SpringConfiguratorTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -44,7 +44,7 @@ public class SpringConfiguratorTests {
 
 
 	@BeforeEach
-	public void setup() {
+	void setup() {
 		this.servletContext = new MockServletContext();
 
 		this.webAppContext = new AnnotationConfigWebApplicationContext();
@@ -57,26 +57,26 @@ public class SpringConfiguratorTests {
 	}
 
 	@AfterEach
-	public void destroy() {
+	void destroy() {
 		this.contextLoader.closeWebApplicationContext(this.servletContext);
 	}
 
 
 	@Test
-	public void getEndpointPerConnection() throws Exception {
+	void getEndpointPerConnection() throws Exception {
 		PerConnectionEchoEndpoint endpoint = this.configurator.getEndpointInstance(PerConnectionEchoEndpoint.class);
 		assertThat(endpoint).isNotNull();
 	}
 
 	@Test
-	public void getEndpointSingletonByType() throws Exception {
+	void getEndpointSingletonByType() throws Exception {
 		EchoEndpoint expected = this.webAppContext.getBean(EchoEndpoint.class);
 		EchoEndpoint actual = this.configurator.getEndpointInstance(EchoEndpoint.class);
 		assertThat(actual).isSameAs(expected);
 	}
 
 	@Test
-	public void getEndpointSingletonByComponentName() throws Exception {
+	void getEndpointSingletonByComponentName() throws Exception {
 		ComponentEchoEndpoint expected = this.webAppContext.getBean(ComponentEchoEndpoint.class);
 		ComponentEchoEndpoint actual = this.configurator.getEndpointInstance(ComponentEchoEndpoint.class);
 		assertThat(actual).isSameAs(expected);
@@ -88,12 +88,12 @@ public class SpringConfiguratorTests {
 	static class Config {
 
 		@Bean
-		public EchoEndpoint javaConfigEndpoint() {
+		EchoEndpoint javaConfigEndpoint() {
 			return new EchoEndpoint(echoService());
 		}
 
 		@Bean
-		public EchoService echoService() {
+		EchoService echoService() {
 			return new EchoService();
 		}
 	}
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/server/support/HttpSessionHandshakeInterceptorTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/server/support/HttpSessionHandshakeInterceptorTests.java
index a2f0f8d2514..33cc315fc4f 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/server/support/HttpSessionHandshakeInterceptorTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/server/support/HttpSessionHandshakeInterceptorTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -35,14 +35,14 @@ import static org.mockito.Mockito.mock;
  *
  * @author Rossen Stoyanchev
  */
-public class HttpSessionHandshakeInterceptorTests extends AbstractHttpRequestTests {
+class HttpSessionHandshakeInterceptorTests extends AbstractHttpRequestTests {
 
 	private final Map<String, Object> attributes = new HashMap<>();
 	private final WebSocketHandler wsHandler = mock();
 
 
 	@Test
-	public void defaultConstructor() throws Exception {
+	void defaultConstructor() throws Exception {
 		this.servletRequest.setSession(new MockHttpSession(null, "123"));
 		this.servletRequest.getSession().setAttribute("foo", "bar");
 		this.servletRequest.getSession().setAttribute("bar", "baz");
@@ -57,7 +57,7 @@ public class HttpSessionHandshakeInterceptorTests extends AbstractHttpRequestTes
 	}
 
 	@Test
-	public void constructorWithAttributeNames() throws Exception {
+	void constructorWithAttributeNames() throws Exception {
 		this.servletRequest.setSession(new MockHttpSession(null, "123"));
 		this.servletRequest.getSession().setAttribute("foo", "bar");
 		this.servletRequest.getSession().setAttribute("bar", "baz");
@@ -72,7 +72,7 @@ public class HttpSessionHandshakeInterceptorTests extends AbstractHttpRequestTes
 	}
 
 	@Test
-	public void doNotCopyHttpSessionId() throws Exception {
+	void doNotCopyHttpSessionId() throws Exception {
 		this.servletRequest.setSession(new MockHttpSession(null, "123"));
 		this.servletRequest.getSession().setAttribute("foo", "bar");
 
@@ -86,7 +86,7 @@ public class HttpSessionHandshakeInterceptorTests extends AbstractHttpRequestTes
 
 
 	@Test
-	public void doNotCopyAttributes() throws Exception {
+	void doNotCopyAttributes() throws Exception {
 		this.servletRequest.setSession(new MockHttpSession(null, "123"));
 		this.servletRequest.getSession().setAttribute("foo", "bar");
 
@@ -99,7 +99,7 @@ public class HttpSessionHandshakeInterceptorTests extends AbstractHttpRequestTes
 	}
 
 	@Test
-	public void doNotCauseSessionCreation() throws Exception {
+	void doNotCauseSessionCreation() throws Exception {
 		HttpSessionHandshakeInterceptor interceptor = new HttpSessionHandshakeInterceptor();
 		interceptor.beforeHandshake(this.request, this.response, wsHandler, attributes);
 
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/server/support/OriginHandshakeInterceptorTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/server/support/OriginHandshakeInterceptorTests.java
index 6577c7bf5cb..e956eb925a8 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/server/support/OriginHandshakeInterceptorTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/server/support/OriginHandshakeInterceptorTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -40,19 +40,19 @@ import static org.mockito.Mockito.mock;
  *
  * @author Sebastien Deleuze
  */
-public class OriginHandshakeInterceptorTests extends AbstractHttpRequestTests {
+class OriginHandshakeInterceptorTests extends AbstractHttpRequestTests {
 
 	private final Map<String, Object> attributes = new HashMap<>();
 	private final WebSocketHandler wsHandler = mock();
 
 
 	@Test
-	public void invalidInput() {
+	void invalidInput() {
 		assertThatIllegalArgumentException().isThrownBy(() -> new OriginHandshakeInterceptor(null));
 	}
 
 	@Test
-	public void originValueMatch() throws Exception {
+	void originValueMatch() throws Exception {
 		this.servletRequest.addHeader(HttpHeaders.ORIGIN, "https://mydomain1.example");
 		List<String> allowed = Collections.singletonList("https://mydomain1.example");
 		OriginHandshakeInterceptor interceptor = new OriginHandshakeInterceptor(allowed);
@@ -61,7 +61,7 @@ public class OriginHandshakeInterceptorTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void originValueNoMatch() throws Exception {
+	void originValueNoMatch() throws Exception {
 		this.servletRequest.addHeader(HttpHeaders.ORIGIN, "https://mydomain1.example");
 		List<String> allowed = Collections.singletonList("https://mydomain2.example");
 		OriginHandshakeInterceptor interceptor = new OriginHandshakeInterceptor(allowed);
@@ -70,7 +70,7 @@ public class OriginHandshakeInterceptorTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void originListMatch() throws Exception {
+	void originListMatch() throws Exception {
 		this.servletRequest.addHeader(HttpHeaders.ORIGIN, "https://mydomain2.example");
 		List<String> allowed = Arrays.asList("https://mydomain1.example", "https://mydomain2.example", "http://mydomain3.example");
 		OriginHandshakeInterceptor interceptor = new OriginHandshakeInterceptor(allowed);
@@ -79,7 +79,7 @@ public class OriginHandshakeInterceptorTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void originListNoMatch() throws Exception {
+	void originListNoMatch() throws Exception {
 		this.servletRequest.addHeader(HttpHeaders.ORIGIN, "http://www.mydomain4.example/");
 		List<String> allowed = Arrays.asList("https://mydomain1.example", "https://mydomain2.example", "http://mydomain3.example");
 		OriginHandshakeInterceptor interceptor = new OriginHandshakeInterceptor(allowed);
@@ -88,7 +88,7 @@ public class OriginHandshakeInterceptorTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void originNoMatchWithNullHostileCollection() throws Exception {
+	void originNoMatchWithNullHostileCollection() throws Exception {
 		this.servletRequest.addHeader(HttpHeaders.ORIGIN, "http://www.mydomain4.example/");
 		OriginHandshakeInterceptor interceptor = new OriginHandshakeInterceptor();
 		Set<String> allowedOrigins = new ConcurrentSkipListSet<>();
@@ -99,7 +99,7 @@ public class OriginHandshakeInterceptorTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void originMatchAll() throws Exception {
+	void originMatchAll() throws Exception {
 		this.servletRequest.addHeader(HttpHeaders.ORIGIN, "https://mydomain1.example");
 		OriginHandshakeInterceptor interceptor = new OriginHandshakeInterceptor();
 		interceptor.setAllowedOrigins(Collections.singletonList("*"));
@@ -108,7 +108,7 @@ public class OriginHandshakeInterceptorTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void sameOriginMatchWithEmptyAllowedOrigins() throws Exception {
+	void sameOriginMatchWithEmptyAllowedOrigins() throws Exception {
 		this.servletRequest.addHeader(HttpHeaders.ORIGIN, "http://mydomain2.example");
 		this.servletRequest.setServerName("mydomain2.example");
 		OriginHandshakeInterceptor interceptor = new OriginHandshakeInterceptor(Collections.emptyList());
@@ -117,7 +117,7 @@ public class OriginHandshakeInterceptorTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void sameOriginMatchWithAllowedOrigins() throws Exception {
+	void sameOriginMatchWithAllowedOrigins() throws Exception {
 		this.servletRequest.addHeader(HttpHeaders.ORIGIN, "http://mydomain2.example");
 		this.servletRequest.setServerName("mydomain2.example");
 		OriginHandshakeInterceptor interceptor = new OriginHandshakeInterceptor(List.of("http://mydomain1.example"));
@@ -126,7 +126,7 @@ public class OriginHandshakeInterceptorTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	public void sameOriginNoMatch() throws Exception {
+	void sameOriginNoMatch() throws Exception {
 		this.servletRequest.addHeader(HttpHeaders.ORIGIN, "http://mydomain3.example");
 		this.servletRequest.setServerName("mydomain2.example");
 		OriginHandshakeInterceptor interceptor = new OriginHandshakeInterceptor(Collections.emptyList());
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/ClientSockJsSessionTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/ClientSockJsSessionTests.java
index ad304205d81..80ca072fc93 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/ClientSockJsSessionTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/ClientSockJsSessionTests.java
@@ -16,7 +16,6 @@
 
 package org.springframework.web.socket.sockjs.client;
 
-import java.io.IOException;
 import java.net.InetSocketAddress;
 import java.net.URI;
 import java.util.List;
@@ -79,7 +78,7 @@ class ClientSockJsSessionTests {
 	}
 
 	@Test
-	void handleFrameOpenWhenStatusNotNew() throws Exception {
+	void handleFrameOpenWhenStatusNotNew() {
 		this.session.handleFrame(SockJsFrame.openFrame().getContent());
 		assertThat(this.session.isOpen()).isTrue();
 		this.session.handleFrame(SockJsFrame.openFrame().getContent());
@@ -183,7 +182,7 @@ class ClientSockJsSessionTests {
 	}
 
 	@Test
-	void closeWithNullStatus() throws Exception {
+	void closeWithNullStatus() {
 		this.session.handleFrame(SockJsFrame.openFrame().getContent());
 		assertThatIllegalArgumentException()
 			.isThrownBy(() -> this.session.close(null))
@@ -191,7 +190,7 @@ class ClientSockJsSessionTests {
 	}
 
 	@Test
-	void closeWithStatusOutOfRange() throws Exception {
+	void closeWithStatusOutOfRange() {
 		this.session.handleFrame(SockJsFrame.openFrame().getContent());
 		assertThatIllegalArgumentException()
 			.isThrownBy(() -> this.session.close(new CloseStatus(2999, "reason")))
@@ -225,12 +224,12 @@ class ClientSockJsSessionTests {
 		}
 
 		@Override
-		protected void sendInternal(TextMessage textMessage) throws IOException {
+		protected void sendInternal(TextMessage textMessage) {
 			this.sentMessage = textMessage;
 		}
 
 		@Override
-		protected void disconnect(CloseStatus status) throws IOException {
+		protected void disconnect(CloseStatus status) {
 			this.disconnectStatus = status;
 		}
 
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/DefaultTransportRequestTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/DefaultTransportRequestTests.java
index 04d000f6d5c..b7c792dfab0 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/DefaultTransportRequestTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/DefaultTransportRequestTests.java
@@ -51,7 +51,6 @@ class DefaultTransportRequestTests {
 
 	private CompletableFuture<WebSocketSession> connectFuture = new CompletableFuture<>();
 
-	@SuppressWarnings("unchecked")
 	private BiConsumer<WebSocketSession, Throwable> connectCallback = mock();
 
 	private TestTransport webSocketTransport = new TestTransport("WebSocketTestTransport");
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/RestTemplateXhrTransportTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/RestTemplateXhrTransportTests.java
index dea8cc1fe57..e32b78c6f2d 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/RestTemplateXhrTransportTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/RestTemplateXhrTransportTests.java
@@ -133,7 +133,7 @@ class RestTemplateXhrTransportTests {
 	void connectFailure() {
 		final HttpServerErrorException expected = new HttpServerErrorException(HttpStatus.INTERNAL_SERVER_ERROR);
 		RestOperations restTemplate = mock();
-		given(restTemplate.execute((URI) any(), eq(HttpMethod.POST), any(), any())).willThrow(expected);
+		given(restTemplate.execute(any(), eq(HttpMethod.POST), any(), any())).willThrow(expected);
 
 		final CountDownLatch latch = new CountDownLatch(1);
 		connect(restTemplate).addCallback(
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/SockJsClientTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/SockJsClientTests.java
index f2df211478d..10da16a5fc8 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/SockJsClientTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/SockJsClientTests.java
@@ -17,7 +17,6 @@
 package org.springframework.web.socket.sockjs.client;
 
 import java.net.URI;
-import java.net.URISyntaxException;
 import java.util.List;
 
 import org.junit.jupiter.api.BeforeEach;
@@ -58,7 +57,7 @@ class SockJsClientTests {
 
 	private final XhrTestTransport xhrTransport = new XhrTestTransport("XhrTestTransport");
 
-	@SuppressWarnings({ "deprecation", "unchecked" })
+	@SuppressWarnings("deprecation")
 	private org.springframework.util.concurrent.ListenableFutureCallback<WebSocketSession> connectCallback = mock();
 
 	private SockJsClient sockJsClient = new SockJsClient(List.of(this.webSocketTransport, this.xhrTransport));
@@ -83,7 +82,7 @@ class SockJsClientTests {
 
 	@Test
 	@SuppressWarnings("deprecation")
-	void connectWebSocketDisabled() throws URISyntaxException {
+	void connectWebSocketDisabled() {
 		setupInfoRequest(false);
 		this.sockJsClient.doHandshake(handler, URL);
 		assertThat(this.webSocketTransport.invoked()).isFalse();
@@ -162,7 +161,7 @@ class SockJsClientTests {
 
 	@Test
 	@SuppressWarnings("deprecation")
-	void connectInfoRequestFailure() throws URISyntaxException {
+	void connectInfoRequestFailure() {
 		HttpServerErrorException exception = new HttpServerErrorException(HttpStatus.SERVICE_UNAVAILABLE);
 		given(this.infoReceiver.executeInfoRequest(any(), any())).willThrow(exception);
 		this.sockJsClient.doHandshake(handler, URL).addCallback(this.connectCallback);
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/TestTransport.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/TestTransport.java
index d153b1fa97c..594ea05bcac 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/TestTransport.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/TestTransport.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -75,7 +75,6 @@ class TestTransport implements Transport {
 		return captor.getValue();
 	}
 
-	@SuppressWarnings("unchecked")
 	@Override
 	public CompletableFuture<WebSocketSession> connectAsync(TransportRequest request, WebSocketHandler handler) {
 		this.request = request;
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/frame/SockJsFrameTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/frame/SockJsFrameTests.java
index 7be85a16c97..80b490152d2 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/frame/SockJsFrameTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/frame/SockJsFrameTests.java
@@ -26,11 +26,11 @@ import static org.assertj.core.api.Assertions.assertThat;
  * @author Rossen Stoyanchev
  * @since 4.1
  */
-public class SockJsFrameTests {
+class SockJsFrameTests {
 
 
 	@Test
-	public void openFrame() {
+	void openFrame() {
 		SockJsFrame frame = SockJsFrame.openFrame();
 
 		assertThat(frame.getContent()).isEqualTo("o");
@@ -39,7 +39,7 @@ public class SockJsFrameTests {
 	}
 
 	@Test
-	public void heartbeatFrame() {
+	void heartbeatFrame() {
 		SockJsFrame frame = SockJsFrame.heartbeatFrame();
 
 		assertThat(frame.getContent()).isEqualTo("h");
@@ -48,7 +48,7 @@ public class SockJsFrameTests {
 	}
 
 	@Test
-	public void messageArrayFrame() {
+	void messageArrayFrame() {
 		SockJsFrame frame = SockJsFrame.messageFrame(new Jackson2SockJsMessageCodec(), "m1", "m2");
 
 		assertThat(frame.getContent()).isEqualTo("a[\"m1\",\"m2\"]");
@@ -57,7 +57,7 @@ public class SockJsFrameTests {
 	}
 
 	@Test
-	public void messageArrayFrameEmpty() {
+	void messageArrayFrameEmpty() {
 		SockJsFrame frame = new SockJsFrame("a");
 
 		assertThat(frame.getContent()).isEqualTo("a[]");
@@ -72,7 +72,7 @@ public class SockJsFrameTests {
 	}
 
 	@Test
-	public void closeFrame() {
+	void closeFrame() {
 		SockJsFrame frame = SockJsFrame.closeFrame(3000, "Go Away!");
 
 		assertThat(frame.getContent()).isEqualTo("c[3000,\"Go Away!\"]");
@@ -81,7 +81,7 @@ public class SockJsFrameTests {
 	}
 
 	@Test
-	public void closeFrameEmpty() {
+	void closeFrameEmpty() {
 		SockJsFrame frame = new SockJsFrame("c");
 
 		assertThat(frame.getContent()).isEqualTo("c[]");
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/support/SockJsServiceTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/support/SockJsServiceTests.java
index 83d1070da7a..a63db42bcd6 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/support/SockJsServiceTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/support/SockJsServiceTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -281,7 +281,7 @@ class SockJsServiceTests extends AbstractHttpRequestTests {
 
 		@Override
 		protected void handleRawWebSocketRequest(ServerHttpRequest req, ServerHttpResponse res,
-				WebSocketHandler handler) throws IOException {
+				WebSocketHandler handler) {
 		}
 
 		@Override
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/TransportTypeTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/TransportTypeTests.java
index a3f651ff67b..f01d7e841ad 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/TransportTypeTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/TransportTypeTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -23,10 +23,10 @@ import static org.assertj.core.api.Assertions.assertThat;
 /**
  * @author Rossen Stoyanchev
  */
-public class TransportTypeTests {
+class TransportTypeTests {
 
 	@Test
-	public void testFromValue() {
+	void testFromValue() {
 		assertThat(TransportType.fromValue("websocket")).isEqualTo(TransportType.WEBSOCKET);
 		assertThat(TransportType.fromValue("xhr")).isEqualTo(TransportType.XHR);
 		assertThat(TransportType.fromValue("xhr_send")).isEqualTo(TransportType.XHR_SEND);
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/DefaultSockJsServiceTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/DefaultSockJsServiceTests.java
index 816fe1bc667..b3ae02493a5 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/DefaultSockJsServiceTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/DefaultSockJsServiceTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -91,7 +91,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 
 	@Override
 	@BeforeEach
-	public void setup() {
+	protected void setup() {
 		super.setup();
 
 		Map<String, Object> attributes = Collections.emptyMap();
@@ -147,7 +147,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	void handleTransportRequestXhr() throws Exception {
+	void handleTransportRequestXhr() {
 		String sockJsPath = sessionUrlPrefix + "xhr";
 		setRequest("POST", sockJsPrefix + sockJsPath);
 		this.service.handleRequest(this.request, this.response, sockJsPath, this.wsHandler);
@@ -162,7 +162,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test  // SPR-12226
-	void handleTransportRequestXhrAllowedOriginsMatch() throws Exception {
+	void handleTransportRequestXhrAllowedOriginsMatch() {
 		String sockJsPath = sessionUrlPrefix + "xhr";
 		setRequest("POST", sockJsPrefix + sockJsPath);
 		this.service.setAllowedOrigins(Arrays.asList("https://mydomain1.example", "https://mydomain2.example"));
@@ -173,7 +173,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test  // SPR-12226
-	void handleTransportRequestXhrAllowedOriginsNoMatch() throws Exception {
+	void handleTransportRequestXhrAllowedOriginsNoMatch() {
 		String sockJsPath = sessionUrlPrefix + "xhr";
 		setRequest("POST", sockJsPrefix + sockJsPath);
 		this.service.setAllowedOrigins(Arrays.asList("https://mydomain1.example", "https://mydomain2.example"));
@@ -184,7 +184,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test  // SPR-13464
-	void handleTransportRequestXhrSameOrigin() throws Exception {
+	void handleTransportRequestXhrSameOrigin() {
 		String sockJsPath = sessionUrlPrefix + "xhr";
 		setRequest("POST", sockJsPrefix + sockJsPath);
 		this.service.setAllowedOrigins(List.of("https://mydomain1.example"));
@@ -196,7 +196,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test  // SPR-13545
-	void handleInvalidTransportType() throws Exception {
+	void handleInvalidTransportType() {
 		String sockJsPath = sessionUrlPrefix + "invalid";
 		setRequest("POST", sockJsPrefix + sockJsPath);
 		this.service.setAllowedOrigins(List.of("https://mydomain1.example"));
@@ -208,7 +208,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	void handleTransportRequestXhrOptions() throws Exception {
+	void handleTransportRequestXhrOptions() {
 		String sockJsPath = sessionUrlPrefix + "xhr";
 		setRequest("OPTIONS", sockJsPrefix + sockJsPath);
 		this.service.handleRequest(this.request, this.response, sockJsPath, this.wsHandler);
@@ -220,7 +220,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	void handleTransportRequestNoSuitableHandler() throws Exception {
+	void handleTransportRequestNoSuitableHandler() {
 		String sockJsPath = sessionUrlPrefix + "eventsource";
 		setRequest("POST", sockJsPrefix + sockJsPath);
 		this.service.handleRequest(this.request, this.response, sockJsPath, this.wsHandler);
@@ -229,7 +229,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	void handleTransportRequestXhrSend() throws Exception {
+	void handleTransportRequestXhrSend() {
 		String sockJsPath = sessionUrlPrefix + "xhr_send";
 		setRequest("POST", sockJsPrefix + sockJsPath);
 		this.service.handleRequest(this.request, this.response, sockJsPath, this.wsHandler);
@@ -258,7 +258,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	void handleTransportRequestXhrSendWithDifferentUser() throws Exception {
+	void handleTransportRequestXhrSendWithDifferentUser() {
 		String sockJsPath = sessionUrlPrefix + "xhr";
 		setRequest("POST", sockJsPrefix + sockJsPath);
 		this.service.handleRequest(this.request, this.response, sockJsPath, this.wsHandler);
@@ -281,7 +281,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	void handleTransportRequestWebsocket() throws Exception {
+	void handleTransportRequestWebsocket() {
 		TransportHandlingSockJsService wsService = new TransportHandlingSockJsService(
 				this.taskScheduler, this.wsTransportHandler);
 		String sockJsPath = "/websocket";
@@ -306,7 +306,7 @@ class DefaultSockJsServiceTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	void handleTransportRequestIframe() throws Exception {
+	void handleTransportRequestIframe() {
 		String sockJsPath = "/iframe.html";
 		setRequest("GET", sockJsPrefix + sockJsPath);
 		this.service.handleRequest(this.request, this.response, sockJsPath, this.wsHandler);
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/HttpReceivingTransportHandlerTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/HttpReceivingTransportHandlerTests.java
index 1ee8d36e5bb..a85f672e5e8 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/HttpReceivingTransportHandlerTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/HttpReceivingTransportHandlerTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -52,7 +52,7 @@ class HttpReceivingTransportHandlerTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	void readMessagesBadContent() throws Exception {
+	void readMessagesBadContent() {
 		this.servletRequest.setContent("".getBytes(UTF_8));
 		handleRequestAndExpectFailure();
 
@@ -61,7 +61,7 @@ class HttpReceivingTransportHandlerTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	void readMessagesNoSession() throws Exception {
+	void readMessagesNoSession() {
 		WebSocketHandler webSocketHandler = mock();
 		assertThatIllegalArgumentException().isThrownBy(() ->
 				new XhrReceivingTransportHandler().handleRequest(this.request, this.response, webSocketHandler, null));
@@ -93,11 +93,11 @@ class HttpReceivingTransportHandlerTests extends AbstractHttpRequestTests {
 		transportHandler.initialize(new StubSockJsServiceConfig());
 		transportHandler.handleRequest(this.request, this.response, wsHandler, session);
 
-		assertThat(this.response.getHeaders().getContentType().toString()).isEqualTo("text/plain;charset=UTF-8");
+		assertThat(this.response.getHeaders().getContentType()).hasToString("text/plain;charset=UTF-8");
 		verify(wsHandler).handleMessage(session, new TextMessage("x"));
 	}
 
-	private void handleRequestAndExpectFailure() throws Exception {
+	private void handleRequestAndExpectFailure() {
 		resetResponse();
 
 		WebSocketHandler wsHandler = mock();
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/HttpSendingTransportHandlerTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/HttpSendingTransportHandlerTests.java
index cf10cf0b7cf..46fcdba687c 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/HttpSendingTransportHandlerTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/HttpSendingTransportHandlerTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -135,7 +135,7 @@ class HttpSendingTransportHandlerTests extends AbstractHttpRequestTests {
 	}
 
 	@Test
-	void frameFormats() throws Exception {
+	void frameFormats() {
 		this.servletRequest.setQueryString("c=callback");
 		this.servletRequest.addParameter("c", "callback");
 
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/SockJsWebSocketHandlerTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/SockJsWebSocketHandlerTests.java
index 7e9cf2ba524..eb471a38431 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/SockJsWebSocketHandlerTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/handler/SockJsWebSocketHandlerTests.java
@@ -36,10 +36,10 @@ import static org.mockito.Mockito.mock;
  *
  * @author Rossen Stoyanchev
  */
-public class SockJsWebSocketHandlerTests {
+class SockJsWebSocketHandlerTests {
 
 	@Test
-	public void getSubProtocols() throws Exception {
+	void getSubProtocols() {
 		SubscribableChannel channel = mock();
 		SubProtocolWebSocketHandler handler = new SubProtocolWebSocketHandler(channel, channel);
 		StompSubProtocolHandler stompHandler = new StompSubProtocolHandler();
@@ -54,7 +54,7 @@ public class SockJsWebSocketHandlerTests {
 	}
 
 	@Test
-	public void getSubProtocolsNone() throws Exception {
+	void getSubProtocolsNone() {
 		WebSocketHandler handler = new TextWebSocketHandler();
 		TaskScheduler scheduler = mock();
 		DefaultSockJsService service = new DefaultSockJsService(scheduler);
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/session/TestSockJsSession.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/session/TestSockJsSession.java
index 53d659d1f38..1e856f420f2 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/session/TestSockJsSession.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/session/TestSockJsSession.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -209,7 +209,7 @@ public class TestSockJsSession extends AbstractSockJsSession {
 	}
 
 	@Override
-	protected void disconnect(CloseStatus status) throws IOException {
+	protected void disconnect(CloseStatus status) {
 		this.closeStatus = status;
 	}
 
diff --git a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/session/WebSocketServerSockJsSessionTests.java b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/session/WebSocketServerSockJsSessionTests.java
index 8f08b82f54b..79733172cb4 100644
--- a/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/session/WebSocketServerSockJsSessionTests.java
+++ b/spring-websocket/src/test/java/org/springframework/web/socket/sockjs/transport/session/WebSocketServerSockJsSessionTests.java
@@ -64,7 +64,7 @@ class WebSocketServerSockJsSessionTests extends AbstractSockJsSessionTests<TestW
 
 
 	@Test
-	void isActive() throws Exception {
+	void isActive() {
 		assertThat(this.session.isActive()).isFalse();
 
 		this.session.initializeDelegateSession(this.webSocketSession);
@@ -85,7 +85,7 @@ class WebSocketServerSockJsSessionTests extends AbstractSockJsSessionTests<TestW
 
 	@Test
 	@SuppressWarnings("resource")
-	void afterSessionInitializedOpenFrameFirst() throws Exception {
+	void afterSessionInitializedOpenFrameFirst() {
 		TextWebSocketHandler handler = new TextWebSocketHandler() {
 			@Override
 			public void afterConnectionEstablished(WebSocketSession session) throws Exception {
@@ -123,7 +123,7 @@ class WebSocketServerSockJsSessionTests extends AbstractSockJsSessionTests<TestW
 	}
 
 	@Test
-	void sendMessageInternal() throws Exception {
+	void sendMessageInternal() {
 		this.session.initializeDelegateSession(this.webSocketSession);
 		this.session.sendMessageInternal("x");