Apply 'instanceof pattern matching' in spring-test and Servlet mocks

spring-test/src/main/java/org/springframework/mock/web/MockBodyContent.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -69,8 +69,8 @@ public class MockBodyContent extends BodyContent {
 	}
 
 	private static JspWriter adaptJspWriter(@Nullable Writer targetWriter, @Nullable HttpServletResponse response) {
-		if (targetWriter instanceof JspWriter) {
-			return (JspWriter) targetWriter;
+		if (targetWriter instanceof JspWriter jspWriter) {
+			return jspWriter;
 		}
 		else {
 			return new MockJspWriter(response, targetWriter);

spring-test/src/main/java/org/springframework/mock/web/MockHttpSession.java

@@ -167,11 +167,11 @@ public class MockHttpSession implements HttpSession {
 		if (value != null) {
 			Object oldValue = this.attributes.put(name, value);
 			if (value != oldValue) {
-				if (oldValue instanceof HttpSessionBindingListener) {
-					((HttpSessionBindingListener) oldValue).valueUnbound(new HttpSessionBindingEvent(this, name, oldValue));
+				if (oldValue instanceof HttpSessionBindingListener listener) {
+					listener.valueUnbound(new HttpSessionBindingEvent(this, name, oldValue));
 				}
-				if (value instanceof HttpSessionBindingListener) {
-					((HttpSessionBindingListener) value).valueBound(new HttpSessionBindingEvent(this, name, value));
+				if (value instanceof HttpSessionBindingListener listener) {
+					listener.valueBound(new HttpSessionBindingEvent(this, name, value));
 				}
 			}
 		}
@@ -185,8 +185,8 @@ public class MockHttpSession implements HttpSession {
 		assertIsValid();
 		Assert.notNull(name, "Attribute name must not be null");
 		Object value = this.attributes.remove(name);
-		if (value instanceof HttpSessionBindingListener) {
-			((HttpSessionBindingListener) value).valueUnbound(new HttpSessionBindingEvent(this, name, value));
+		if (value instanceof HttpSessionBindingListener listener) {
+			listener.valueUnbound(new HttpSessionBindingEvent(this, name, value));
 		}
 	}
 
@@ -199,8 +199,8 @@ public class MockHttpSession implements HttpSession {
 			String name = entry.getKey();
 			Object value = entry.getValue();
 			it.remove();
-			if (value instanceof HttpSessionBindingListener) {
-				((HttpSessionBindingListener) value).valueUnbound(new HttpSessionBindingEvent(this, name, value));
+			if (value instanceof HttpSessionBindingListener listener) {
+				listener.valueUnbound(new HttpSessionBindingEvent(this, name, value));
 			}
 		}
 	}
@@ -251,14 +251,14 @@ public class MockHttpSession implements HttpSession {
 			String name = entry.getKey();
 			Object value = entry.getValue();
 			it.remove();
-			if (value instanceof Serializable) {
-				state.put(name, (Serializable) value);
+			if (value instanceof Serializable serializable) {
+				state.put(name, serializable);
 			}
 			else {
 				// Not serializable... Servlet containers usually automatically
 				// unbind the attribute in this case.
-				if (value instanceof HttpSessionBindingListener) {
-					((HttpSessionBindingListener) value).valueUnbound(new HttpSessionBindingEvent(this, name, value));
+				if (value instanceof HttpSessionBindingListener listener) {
+					listener.valueUnbound(new HttpSessionBindingEvent(this, name, value));
 				}
 			}
 		}

spring-test/src/main/java/org/springframework/mock/web/MockJspWriter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -65,8 +65,8 @@ public class MockJspWriter extends JspWriter {
 	public MockJspWriter(@Nullable HttpServletResponse response, @Nullable Writer targetWriter) {
 		super(DEFAULT_BUFFER, true);
 		this.response = (response != null ? response : new MockHttpServletResponse());
-		if (targetWriter instanceof PrintWriter) {
-			this.targetWriter = (PrintWriter) targetWriter;
+		if (targetWriter instanceof PrintWriter printWriter) {
+			this.targetWriter = printWriter;
 		}
 		else if (targetWriter != null) {
 			this.targetWriter = new PrintWriter(targetWriter);

spring-test/src/main/java/org/springframework/mock/web/MockPageContext.java

@@ -342,13 +342,17 @@ public class MockPageContext extends PageContext {
 	}
 
 	public byte[] getContentAsByteArray() {
-		Assert.state(this.response instanceof MockHttpServletResponse, "MockHttpServletResponse required");
-		return ((MockHttpServletResponse) this.response).getContentAsByteArray();
+		if (this.response instanceof MockHttpServletResponse mockResponse) {
+			return mockResponse.getContentAsByteArray();
+		}
+		throw new IllegalStateException("MockHttpServletResponse is required");
 	}
 
 	public String getContentAsString() throws UnsupportedEncodingException {
-		Assert.state(this.response instanceof MockHttpServletResponse, "MockHttpServletResponse required");
-		return ((MockHttpServletResponse) this.response).getContentAsString();
+		if (this.response instanceof MockHttpServletResponse mockResponse) {
+			return mockResponse.getContentAsString();
+		}
+		throw new IllegalStateException("MockHttpServletResponse is required");
 	}
 
 	@Override

spring-test/src/main/java/org/springframework/mock/web/MockRequestDispatcher.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -78,11 +78,11 @@ public class MockRequestDispatcher implements RequestDispatcher {
 	 * {@link HttpServletResponseWrapper} decorators if necessary.
 	 */
 	protected MockHttpServletResponse getMockHttpServletResponse(ServletResponse response) {
-		if (response instanceof MockHttpServletResponse) {
-			return (MockHttpServletResponse) response;
+		if (response instanceof MockHttpServletResponse mockResponse) {
+			return mockResponse;
 		}
-		if (response instanceof HttpServletResponseWrapper) {
-			return getMockHttpServletResponse(((HttpServletResponseWrapper) response).getResponse());
+		if (response instanceof HttpServletResponseWrapper wrapper) {
+			return getMockHttpServletResponse(wrapper.getResponse());
 		}
 		throw new IllegalArgumentException("MockRequestDispatcher requires MockHttpServletResponse");
 	}

spring-test/src/main/java/org/springframework/test/context/jdbc/MergedSqlConfig.java

@@ -291,7 +291,7 @@ class MergedSqlConfig {
 	}
 
 	private static boolean isEmptyString(@Nullable Object value) {
-		return (value instanceof String && ((String) value).isEmpty());
+		return (value instanceof String str && str.isEmpty());
 	}
 
 	private static boolean isEmptyArray(@Nullable Object value) {

spring-test/src/main/java/org/springframework/test/context/junit/jupiter/AbstractExpressionEvaluatingCondition.java

@@ -138,8 +138,7 @@ abstract class AbstractExpressionEvaluatingCondition implements ExecutionConditi
 		// since the DirtiesContextTestExecutionListener will never be invoked for
 		// a disabled test class.
 		// See https://github.com/spring-projects/spring-framework/issues/26694
-		if (loadContext && result.isDisabled() && element instanceof Class) {
-			Class<?> testClass = (Class<?>) element;
+		if (loadContext && result.isDisabled() && element instanceof Class<?> testClass) {
 			DirtiesContext dirtiesContext = TestContextAnnotationUtils.findMergedAnnotation(testClass, DirtiesContext.class);
 			if (dirtiesContext != null) {
 				HierarchyMode hierarchyMode = dirtiesContext.hierarchyMode();
@@ -167,7 +166,7 @@ abstract class AbstractExpressionEvaluatingCondition implements ExecutionConditi
 			applicationContext = gac;
 		}
 
-		if (!(applicationContext instanceof ConfigurableApplicationContext)) {
+		if (!(applicationContext instanceof ConfigurableApplicationContext cac)) {
 			if (logger.isWarnEnabled()) {
 				String contextType = applicationContext.getClass().getName();
 				logger.warn(String.format("@%s(\"%s\") could not be evaluated on [%s] since the test " +
@@ -177,7 +176,7 @@ abstract class AbstractExpressionEvaluatingCondition implements ExecutionConditi
 			return false;
 		}
 
-		ConfigurableBeanFactory configurableBeanFactory = ((ConfigurableApplicationContext) applicationContext).getBeanFactory();
+		ConfigurableBeanFactory configurableBeanFactory = cac.getBeanFactory();
 		BeanExpressionResolver expressionResolver = configurableBeanFactory.getBeanExpressionResolver();
 		Assert.state(expressionResolver != null, "No BeanExpressionResolver");
 		BeanExpressionContext beanExpressionContext = new BeanExpressionContext(configurableBeanFactory, null);
@@ -189,11 +188,11 @@ abstract class AbstractExpressionEvaluatingCondition implements ExecutionConditi
 			gac.close();
 		}
 
-		if (result instanceof Boolean) {
-			return (Boolean) result;
+		if (result instanceof Boolean b) {
+			return b;
 		}
-		else if (result instanceof String) {
-			String str = ((String) result).trim().toLowerCase();
+		else if (result instanceof String str) {
+			str = str.trim().toLowerCase();
 			if ("true".equals(str)) {
 				return true;
 			}

spring-test/src/main/java/org/springframework/test/context/support/TestConstructorUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -86,8 +86,8 @@ public abstract class TestConstructorUtils {
 	public static boolean isAutowirableConstructor(Executable executable, Class<?> testClass,
 			@Nullable PropertyProvider fallbackPropertyProvider) {
 
-		return (executable instanceof Constructor &&
-				isAutowirableConstructor((Constructor<?>) executable, testClass, fallbackPropertyProvider));
+		return (executable instanceof Constructor<?> constructor &&
+				isAutowirableConstructor(constructor, testClass, fallbackPropertyProvider));
 	}
 
 	/**

spring-test/src/main/java/org/springframework/test/context/web/ServletTestExecutionListener.java

@@ -32,7 +32,6 @@ import org.springframework.test.context.TestContext;
 import org.springframework.test.context.TestExecutionListener;
 import org.springframework.test.context.support.AbstractTestExecutionListener;
 import org.springframework.test.context.support.DependencyInjectionTestExecutionListener;
-import org.springframework.util.Assert;
 import org.springframework.web.context.WebApplicationContext;
 import org.springframework.web.context.request.RequestAttributes;
 import org.springframework.web.context.request.RequestContextHolder;
@@ -193,9 +192,11 @@ public class ServletTestExecutionListener extends AbstractTestExecutionListener
 
 		if (context instanceof WebApplicationContext wac) {
 			ServletContext servletContext = wac.getServletContext();
-			Assert.state(servletContext instanceof MockServletContext, () -> String.format(
-						"The WebApplicationContext for test context %s must be configured with a MockServletContext.",
-						testContext));
+			if (!(servletContext instanceof MockServletContext mockServletContext)) {
+				throw new IllegalStateException(
+						"The WebApplicationContext for test context %s must be configured with a MockServletContext."
+							.formatted(testContext));
+			}
 
 			if (logger.isTraceEnabled()) {
 				logger.trace("Setting up MockHttpServletRequest, MockHttpServletResponse, ServletWebRequest, " +
@@ -206,7 +207,6 @@ public class ServletTestExecutionListener extends AbstractTestExecutionListener
 						"and RequestContextHolder for test class " + testContext.getTestClass().getName());
 			}
 
-			MockServletContext mockServletContext = (MockServletContext) servletContext;
 			MockHttpServletRequest request = new MockHttpServletRequest(mockServletContext);
 			request.setAttribute(CREATED_BY_THE_TESTCONTEXT_FRAMEWORK, Boolean.TRUE);
 			MockHttpServletResponse response = new MockHttpServletResponse();

spring-test/src/main/java/org/springframework/test/web/client/match/ContentRequestMatchers.java

@@ -235,8 +235,8 @@ public class ContentRequestMatchers {
 				for (int i = 0; i < values.size(); i++) {
 					Object expected = values.get(i);
 					Object actual = actualMap.get(name).get(i);
-					if (expected instanceof Resource) {
-						expected = StreamUtils.copyToByteArray(((Resource) expected).getInputStream());
+					if (expected instanceof Resource resource) {
+						expected = StreamUtils.copyToByteArray(resource.getInputStream());
 					}
 					if (expected instanceof byte[]) {
 						assertTrue("Multipart is not a file", actual instanceof byte[]);

spring-test/src/main/java/org/springframework/test/web/reactive/server/WiretapConnector.java

@@ -280,8 +280,8 @@ class WiretapConnector implements ClientHttpConnector {
 
 		@Nullable
 		public Object getMockServerResult() {
-			return (getDelegate() instanceof MockServerClientHttpResponse ?
-					((MockServerClientHttpResponse) getDelegate()).getServerResult() : null);
+			return (getDelegate() instanceof MockServerClientHttpResponse mockResponse ?
+					mockResponse.getServerResult() : null);
 		}
 	}
 

spring-test/src/main/java/org/springframework/test/web/servlet/MockMvc.java

@@ -165,8 +165,8 @@ public final class MockMvc {
 	 * @see org.springframework.test.web.servlet.result.MockMvcResultMatchers
 	 */
 	public ResultActions perform(RequestBuilder requestBuilder) throws Exception {
-		if (this.defaultRequestBuilder != null && requestBuilder instanceof Mergeable) {
-			requestBuilder = (RequestBuilder) ((Mergeable) requestBuilder).merge(this.defaultRequestBuilder);
+		if (this.defaultRequestBuilder != null && requestBuilder instanceof Mergeable mergeable) {
+			requestBuilder = (RequestBuilder) mergeable.merge(this.defaultRequestBuilder);
 		}
 
 		MockHttpServletRequest request = requestBuilder.buildRequest(this.servletContext);
@@ -187,8 +187,8 @@ public final class MockMvc {
 			mockResponse.setDefaultCharacterEncoding(this.defaultResponseCharacterEncoding.name());
 		}
 
-		if (requestBuilder instanceof SmartRequestBuilder) {
-			request = ((SmartRequestBuilder) requestBuilder).postProcessRequest(request);
+		if (requestBuilder instanceof SmartRequestBuilder smartRequestBuilder) {
+			request = smartRequestBuilder.postProcessRequest(request);
 		}
 
 		MvcResult mvcResult = new DefaultMvcResult(request, mockResponse);
@@ -227,8 +227,8 @@ public final class MockMvc {
 	}
 
 	private MockHttpServletResponse unwrapResponseIfNecessary(ServletResponse servletResponse) {
-		while (servletResponse instanceof HttpServletResponseWrapper) {
-			servletResponse = ((HttpServletResponseWrapper) servletResponse).getResponse();
+		while (servletResponse instanceof HttpServletResponseWrapper wrapper) {
+			servletResponse = wrapper.getResponse();
 		}
 		Assert.isInstanceOf(MockHttpServletResponse.class, servletResponse);
 		return (MockHttpServletResponse) servletResponse;

spring-test/src/main/java/org/springframework/test/web/servlet/TestDispatcherServlet.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -73,8 +73,8 @@ final class TestDispatcherServlet extends DispatcherServlet {
 
 		if (request.getAsyncContext() != null) {
 			MockAsyncContext asyncContext;
-			if (request.getAsyncContext() instanceof MockAsyncContext) {
-				asyncContext = (MockAsyncContext) request.getAsyncContext();
+			if (request.getAsyncContext() instanceof MockAsyncContext mockAsyncContext) {
+				asyncContext = mockAsyncContext;
 			}
 			else {
 				MockHttpServletRequest mockRequest = WebUtils.getNativeRequest(request, MockHttpServletRequest.class);

spring-test/src/main/java/org/springframework/test/web/servlet/client/MockMvcHttpConnector.java

@@ -167,8 +167,8 @@ public class MockMvcHttpConnector implements ClientHttpConnector {
 									DataBufferUtils.release(buffer);
 
 									// Adapt to jakarta.servlet.http.Part...
-									MockPart mockPart = (part instanceof FilePart ?
-											new MockPart(part.name(), ((FilePart) part).filename(), partBytes) :
+									MockPart mockPart = (part instanceof FilePart filePart ?
+											new MockPart(part.name(), filePart.filename(), partBytes) :
 											new MockPart(part.name(), partBytes));
 									mockPart.getHeaders().putAll(part.headers());
 									requestBuilder.part(mockPart);

spring-test/src/main/java/org/springframework/test/web/servlet/client/MockMvcWebTestClient.java

@@ -36,7 +36,6 @@ import org.springframework.test.web.servlet.ResultMatcher;
 import org.springframework.test.web.servlet.setup.ConfigurableMockMvcBuilder;
 import org.springframework.test.web.servlet.setup.MockMvcConfigurer;
 import org.springframework.test.web.servlet.setup.StandaloneMockMvcBuilder;
-import org.springframework.util.Assert;
 import org.springframework.validation.Validator;
 import org.springframework.web.accept.ContentNegotiationManager;
 import org.springframework.web.context.WebApplicationContext;
@@ -140,22 +139,25 @@ public interface MockMvcWebTestClient {
 	 */
 	static ResultActions resultActionsFor(ExchangeResult exchangeResult) {
 		Object serverResult = exchangeResult.getMockServerResult();
-		Assert.notNull(serverResult, "No MvcResult");
-		Assert.isInstanceOf(MvcResult.class, serverResult);
+		if (!(serverResult instanceof MvcResult mvcResult)) {
+			throw new IllegalArgumentException(
+					"Result from mock server exchange must be an instance of MvcResult instead of " +
+							(serverResult != null ? serverResult.getClass().getName() : "null"));
+		}
 		return new ResultActions() {
 			@Override
 			public ResultActions andExpect(ResultMatcher matcher) throws Exception {
-				matcher.match((MvcResult) serverResult);
+				matcher.match(mvcResult);
 				return this;
 			}
 			@Override
 			public ResultActions andDo(ResultHandler handler) throws Exception {
-				handler.handle((MvcResult) serverResult);
+				handler.handle(mvcResult);
 				return this;
 			}
 			@Override
 			public MvcResult andReturn() {
-				return (MvcResult) serverResult;
+				return mvcResult;
 			}
 		};
 	}

spring-test/src/main/java/org/springframework/test/web/servlet/htmlunit/HtmlUnitRequestBuilder.java

@@ -423,17 +423,17 @@ final class HtmlUnitRequestBuilder implements RequestBuilder, Mergeable {
 
 	@Override
 	public Object merge(@Nullable Object parent) {
-		if (parent instanceof RequestBuilder) {
+		if (parent instanceof RequestBuilder requestBuilder) {
 			if (parent instanceof MockHttpServletRequestBuilder) {
 				MockHttpServletRequestBuilder copiedParent = MockMvcRequestBuilders.get("/");
 				copiedParent.merge(parent);
 				this.parentBuilder = copiedParent;
 			}
 			else {
-				this.parentBuilder = (RequestBuilder) parent;
+				this.parentBuilder = requestBuilder;
 			}
-			if (parent instanceof SmartRequestBuilder) {
-				this.parentPostProcessor = (SmartRequestBuilder) parent;
+			if (parent instanceof SmartRequestBuilder smartRequestBuilder) {
+				this.parentPostProcessor = smartRequestBuilder;
 			}
 		}
 		return this;

spring-test/src/main/java/org/springframework/test/web/servlet/request/MockMultipartHttpServletRequestBuilder.java

@@ -98,7 +98,7 @@ public class MockMultipartHttpServletRequestBuilder extends MockHttpServletReque
 
 
 	/**
-	 * Create a new MockMultipartFile with the given content.
+	 * Add a new {@link MockMultipartFile} with the given content.
 	 * @param name the name of the file
 	 * @param content the content of the file
 	 */
@@ -108,7 +108,7 @@ public class MockMultipartHttpServletRequestBuilder extends MockHttpServletReque
 	}
 
 	/**
-	 * Add the given MockMultipartFile.
+	 * Add the given {@link MockMultipartFile}.
 	 * @param file the multipart file
 	 */
 	public MockMultipartHttpServletRequestBuilder file(MockMultipartFile file) {
@@ -141,7 +141,6 @@ public class MockMultipartHttpServletRequestBuilder extends MockHttpServletReque
 				parentBuilder.parts.keySet().forEach(name ->
 						this.parts.putIfAbsent(name, parentBuilder.parts.get(name)));
 			}
-
 		}
 		else {
 			throw new IllegalArgumentException("Cannot merge with [" + parent.getClass().getName() + "]");
@@ -193,4 +192,5 @@ public class MockMultipartHttpServletRequestBuilder extends MockHttpServletReque
 		}
 		return defaultCharset;
 	}
+
 }

spring-test/src/main/java/org/springframework/test/web/servlet/result/HandlerResultMatchers.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -33,7 +33,6 @@ import static org.hamcrest.MatcherAssert.assertThat;
 import static org.springframework.test.util.AssertionErrors.assertEquals;
 import static org.springframework.test.util.AssertionErrors.assertNotNull;
 import static org.springframework.test.util.AssertionErrors.assertTrue;
-import static org.springframework.test.util.AssertionErrors.fail;
 
 /**
  * Factory for assertions on the selected handler or handler method.
@@ -68,8 +67,8 @@ public class HandlerResultMatchers {
 			Object handler = result.getHandler();
 			assertNotNull("No handler", handler);
 			Class<?> actual = handler.getClass();
-			if (handler instanceof HandlerMethod) {
-				actual = ((HandlerMethod) handler).getBeanType();
+			if (handler instanceof HandlerMethod handlerMethod) {
+				actual = handlerMethod.getBeanType();
 			}
 			assertEquals("Handler type", type, ClassUtils.getUserClass(actual));
 		};
@@ -101,12 +100,12 @@ public class HandlerResultMatchers {
 	 */
 	public ResultMatcher methodCall(Object obj) {
 		return result -> {
-			if (!(obj instanceof MethodInvocationInfo)) {
-				fail(String.format("The supplied object [%s] is not an instance of %s. " +
-						"Ensure that you invoke the handler method via MvcUriComponentsBuilder.on().",
-						obj, MethodInvocationInfo.class.getName()));
+			if (!(obj instanceof MethodInvocationInfo invocationInfo)) {
+				throw new AssertionError("""
+						The supplied object [%s] is not an instance of %s. Ensure \
+						that you invoke the handler method via MvcUriComponentsBuilder.on()."""
+							.formatted(obj, MethodInvocationInfo.class.getName()));
 			}
-			MethodInvocationInfo invocationInfo = (MethodInvocationInfo) obj;
 			Method expected = invocationInfo.getControllerMethod();
 			Method actual = getHandlerMethod(result).getMethod();
 			assertEquals("Handler method", expected, actual);

spring-test/src/main/java/org/springframework/test/web/servlet/result/ModelResultMatchers.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -214,8 +214,8 @@ public class ModelResultMatchers {
 		return result -> {
 			ModelAndView mav = getModelAndView(result);
 			for (Object value : mav.getModel().values()) {
-				if (value instanceof Errors) {
-					assertFalse("Unexpected binding/validation errors: " + value, ((Errors) value).hasErrors());
+				if (value instanceof Errors errors) {
+					assertFalse("Unexpected binding/validation errors: " + value, errors.hasErrors());
 				}
 			}
 		};
@@ -252,8 +252,8 @@ public class ModelResultMatchers {
 	private int getErrorCount(ModelMap model) {
 		int count = 0;
 		for (Object value : model.values()) {
-			if (value instanceof Errors) {
-				count += ((Errors) value).getErrorCount();
+			if (value instanceof Errors errors) {
+				count += errors.getErrorCount();
 			}
 		}
 		return count;

spring-test/src/main/java/org/springframework/test/web/servlet/setup/AbstractMockMvcBuilder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -164,8 +164,8 @@ public abstract class AbstractMockMvcBuilder<B extends AbstractMockMvcBuilder<B>
 				if (this.defaultRequestBuilder == null) {
 					this.defaultRequestBuilder = MockMvcRequestBuilders.get("/");
 				}
-				if (this.defaultRequestBuilder instanceof ConfigurableSmartRequestBuilder) {
-					((ConfigurableSmartRequestBuilder) this.defaultRequestBuilder).with(processor);
+				if (this.defaultRequestBuilder instanceof ConfigurableSmartRequestBuilder configurableBuilder) {
+					configurableBuilder.with(processor);
 				}
 			}
 		}

spring-web/src/testFixtures/java/org/springframework/web/testfixture/servlet/MockBodyContent.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -69,8 +69,8 @@ public class MockBodyContent extends BodyContent {
 	}
 
 	private static JspWriter adaptJspWriter(@Nullable Writer targetWriter, @Nullable HttpServletResponse response) {
-		if (targetWriter instanceof JspWriter) {
-			return (JspWriter) targetWriter;
+		if (targetWriter instanceof JspWriter jspWriter) {
+			return jspWriter;
 		}
 		else {
 			return new MockJspWriter(response, targetWriter);

spring-web/src/testFixtures/java/org/springframework/web/testfixture/servlet/MockHttpSession.java

@@ -167,11 +167,11 @@ public class MockHttpSession implements HttpSession {
 		if (value != null) {
 			Object oldValue = this.attributes.put(name, value);
 			if (value != oldValue) {
-				if (oldValue instanceof HttpSessionBindingListener) {
-					((HttpSessionBindingListener) oldValue).valueUnbound(new HttpSessionBindingEvent(this, name, oldValue));
+				if (oldValue instanceof HttpSessionBindingListener listener) {
+					listener.valueUnbound(new HttpSessionBindingEvent(this, name, oldValue));
 				}
-				if (value instanceof HttpSessionBindingListener) {
-					((HttpSessionBindingListener) value).valueBound(new HttpSessionBindingEvent(this, name, value));
+				if (value instanceof HttpSessionBindingListener listener) {
+					listener.valueBound(new HttpSessionBindingEvent(this, name, value));
 				}
 			}
 		}
@@ -185,8 +185,8 @@ public class MockHttpSession implements HttpSession {
 		assertIsValid();
 		Assert.notNull(name, "Attribute name must not be null");
 		Object value = this.attributes.remove(name);
-		if (value instanceof HttpSessionBindingListener) {
-			((HttpSessionBindingListener) value).valueUnbound(new HttpSessionBindingEvent(this, name, value));
+		if (value instanceof HttpSessionBindingListener listener) {
+			listener.valueUnbound(new HttpSessionBindingEvent(this, name, value));
 		}
 	}
 
@@ -199,8 +199,8 @@ public class MockHttpSession implements HttpSession {
 			String name = entry.getKey();
 			Object value = entry.getValue();
 			it.remove();
-			if (value instanceof HttpSessionBindingListener) {
-				((HttpSessionBindingListener) value).valueUnbound(new HttpSessionBindingEvent(this, name, value));
+			if (value instanceof HttpSessionBindingListener listener) {
+				listener.valueUnbound(new HttpSessionBindingEvent(this, name, value));
 			}
 		}
 	}
@@ -251,14 +251,14 @@ public class MockHttpSession implements HttpSession {
 			String name = entry.getKey();
 			Object value = entry.getValue();
 			it.remove();
-			if (value instanceof Serializable) {
-				state.put(name, (Serializable) value);
+			if (value instanceof Serializable serializable) {
+				state.put(name, serializable);
 			}
 			else {
 				// Not serializable... Servlet containers usually automatically
 				// unbind the attribute in this case.
-				if (value instanceof HttpSessionBindingListener) {
-					((HttpSessionBindingListener) value).valueUnbound(new HttpSessionBindingEvent(this, name, value));
+				if (value instanceof HttpSessionBindingListener listener) {
+					listener.valueUnbound(new HttpSessionBindingEvent(this, name, value));
 				}
 			}
 		}

spring-web/src/testFixtures/java/org/springframework/web/testfixture/servlet/MockJspWriter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -65,8 +65,8 @@ public class MockJspWriter extends JspWriter {
 	public MockJspWriter(@Nullable HttpServletResponse response, @Nullable Writer targetWriter) {
 		super(DEFAULT_BUFFER, true);
 		this.response = (response != null ? response : new MockHttpServletResponse());
-		if (targetWriter instanceof PrintWriter) {
-			this.targetWriter = (PrintWriter) targetWriter;
+		if (targetWriter instanceof PrintWriter printWriter) {
+			this.targetWriter = printWriter;
 		}
 		else if (targetWriter != null) {
 			this.targetWriter = new PrintWriter(targetWriter);

spring-web/src/testFixtures/java/org/springframework/web/testfixture/servlet/MockPageContext.java

@@ -342,13 +342,17 @@ public class MockPageContext extends PageContext {
 	}
 
 	public byte[] getContentAsByteArray() {
-		Assert.state(this.response instanceof MockHttpServletResponse, "MockHttpServletResponse required");
-		return ((MockHttpServletResponse) this.response).getContentAsByteArray();
+		if (this.response instanceof MockHttpServletResponse mockResponse) {
+			return mockResponse.getContentAsByteArray();
+		}
+		throw new IllegalStateException("MockHttpServletResponse is required");
 	}
 
 	public String getContentAsString() throws UnsupportedEncodingException {
-		Assert.state(this.response instanceof MockHttpServletResponse, "MockHttpServletResponse required");
-		return ((MockHttpServletResponse) this.response).getContentAsString();
+		if (this.response instanceof MockHttpServletResponse mockResponse) {
+			return mockResponse.getContentAsString();
+		}
+		throw new IllegalStateException("MockHttpServletResponse is required");
 	}
 
 	@Override

spring-web/src/testFixtures/java/org/springframework/web/testfixture/servlet/MockRequestDispatcher.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -78,11 +78,11 @@ public class MockRequestDispatcher implements RequestDispatcher {
 	 * {@link HttpServletResponseWrapper} decorators if necessary.
 	 */
 	protected MockHttpServletResponse getMockHttpServletResponse(ServletResponse response) {
-		if (response instanceof MockHttpServletResponse) {
-			return (MockHttpServletResponse) response;
+		if (response instanceof MockHttpServletResponse mockResponse) {
+			return mockResponse;
 		}
-		if (response instanceof HttpServletResponseWrapper) {
-			return getMockHttpServletResponse(((HttpServletResponseWrapper) response).getResponse());
+		if (response instanceof HttpServletResponseWrapper wrapper) {
+			return getMockHttpServletResponse(wrapper.getResponse());
 		}
 		throw new IllegalArgumentException("MockRequestDispatcher requires MockHttpServletResponse");
 	}