Turn registered controller classes into controller instances on the fly

Issue: SPR-16520

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

@@ -17,10 +17,10 @@
 package org.springframework.test.web.reactive.server;
 
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.List;
 import java.util.function.Consumer;
 
+import org.springframework.beans.BeanUtils;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.format.FormatterRegistry;
@@ -56,21 +56,24 @@ class DefaultControllerSpec extends AbstractMockServerSpec<WebTestClient.Control
 
 	DefaultControllerSpec(Object... controllers) {
 		Assert.isTrue(!ObjectUtils.isEmpty(controllers), "At least one controller is required");
-		Assert.isTrue(checkInstances(controllers), "Controller instances are required");
+		this.controllers = instantiateIfNecessary(controllers);
-		this.controllers = Arrays.asList(controllers);
 	}
 
+	private static List<Object> instantiateIfNecessary(Object[] specified) {
+		List<Object> instances = new ArrayList<>(specified.length);
+		for (Object obj : specified) {
+			instances.add(obj instanceof Class ? BeanUtils.instantiateClass((Class<?>) obj) : obj);
+		}
+		return instances;
+	}
+
+
 	@Override
-	public DefaultControllerSpec controllerAdvice(Object... controllerAdvice) {
+	public DefaultControllerSpec controllerAdvice(Object... controllerAdvices) {
-		Assert.isTrue(checkInstances(controllerAdvice), "ControllerAdvice instances are required");
+		this.controllerAdvice.addAll(instantiateIfNecessary(controllerAdvices));
-		this.controllerAdvice.addAll(Arrays.asList(controllerAdvice));
 		return this;
 	}
 
-	private boolean checkInstances(Object[] objects) {
-		return Arrays.stream(objects).noneMatch(Class.class::isInstance);
-	}
-
 	@Override
 	public DefaultControllerSpec contentTypeResolver(Consumer<RequestedContentTypeResolverBuilder> consumer) {
 		this.configurer.contentTypeResolverConsumer = consumer;

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -168,6 +168,7 @@ public interface WebTestClient {
 	 * WebFlux application will be tested without an HTTP server using a mock
 	 * request and response.
 	 * @param controllers one or more controller instances to tests
+	 * (specified {@code Class} will be turned into instance)
 	 * @return chained API to customize server and client config; use
 	 * {@link MockServerSpec#configureClient()} to transition to client config
 	 */
@@ -290,9 +291,8 @@ public interface WebTestClient {
 	interface ControllerSpec extends MockServerSpec<ControllerSpec> {
 
 		/**
-		 * Register one or more
+		 * Register one or more {@link org.springframework.web.bind.annotation.ControllerAdvice}
-		 * {@link org.springframework.web.bind.annotation.ControllerAdvice
+		 * instances to be used in tests (specified {@code Class} will be turned into instance).
-		 * ControllerAdvice} instances to be used in tests.
 		 */
 		ControllerSpec controllerAdvice(Object... controllerAdvice);
 

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -51,25 +51,22 @@ public class MockMvcBuilders {
 	 * Build a {@link MockMvc} instance by registering one or more
 	 * {@code @Controller} instances and configuring Spring MVC infrastructure
 	 * programmatically.
-	 *
 	 * <p>This allows full control over the instantiation and initialization of
 	 * controllers and their dependencies, similar to plain unit tests while
 	 * also making it possible to test one controller at a time.
-	 *
 	 * <p>When this builder is used, the minimum infrastructure required by the
 	 * {@link org.springframework.web.servlet.DispatcherServlet DispatcherServlet}
 	 * to serve requests with annotated controllers is created automatically
 	 * and can be customized, resulting in configuration that is equivalent to
 	 * what MVC Java configuration provides except using builder-style methods.
-	 *
 	 * <p>If the Spring MVC configuration of an application is relatively
 	 * straight-forward &mdash; for example, when using the MVC namespace in
 	 * XML or MVC Java config &mdash; then using this builder might be a good
 	 * option for testing a majority of controllers. In such cases, a much
 	 * smaller number of tests can be used to focus on testing and verifying
 	 * the actual Spring MVC configuration.
-	 *
 	 * @param controllers one or more {@code @Controller} instances to test
+	 * (specified {@code Class} will be turned into instance)
 	 */
 	public static StandaloneMockMvcBuilder standaloneSetup(Object... controllers) {
 		return new StandaloneMockMvcBuilder(controllers);

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

@@ -26,6 +26,7 @@ import java.util.Map;
 import java.util.function.Supplier;
 import javax.servlet.ServletContext;
 
+import org.springframework.beans.BeanUtils;
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.BeanInitializationException;
 import org.springframework.beans.factory.InitializingBean;
@@ -37,7 +38,6 @@ import org.springframework.http.converter.HttpMessageConverter;
 import org.springframework.lang.Nullable;
 import org.springframework.mock.web.MockServletContext;
 import org.springframework.util.Assert;
-import org.springframework.util.ObjectUtils;
 import org.springframework.util.PropertyPlaceholderHelper;
 import org.springframework.util.PropertyPlaceholderHelper.PlaceholderResolver;
 import org.springframework.util.StringValueResolver;
@@ -142,31 +142,31 @@ public class StandaloneMockMvcBuilder extends AbstractMockMvcBuilder<StandaloneM
 	 * @see MockMvcBuilders#standaloneSetup(Object...)
 	 */
 	protected StandaloneMockMvcBuilder(Object... controllers) {
-		Assert.isTrue(!ObjectUtils.isEmpty(controllers), "At least one controller is required");
+		this.controllers = instantiateIfNecessary(controllers);
-		Assert.isTrue(checkInstances(controllers), "Controller instances are required");
-		this.controllers = Arrays.asList(controllers);
 	}
 
+	private static List<Object> instantiateIfNecessary(Object[] specified) {
+		List<Object> instances = new ArrayList<>(specified.length);
+		for (Object obj : specified) {
+			instances.add(obj instanceof Class ? BeanUtils.instantiateClass((Class<?>) obj) : obj);
+		}
+		return instances;
+	}
+
+
 	/**
-	 * Register one or more
+	 * Register one or more {@link org.springframework.web.bind.annotation.ControllerAdvice}
-	 * {@link org.springframework.web.bind.annotation.ControllerAdvice
+	 * instances to be used in tests (specified {@code Class} will be turned into instance).
-	 * ControllerAdvice} instances to be used in tests.
+	 * <p>Normally {@code @ControllerAdvice} are auto-detected as long as they're declared
-	 * <p>Normally {@code @ControllerAdvice} are auto-detected as long as they're
+	 * as Spring beans. However since the standalone setup does not load any Spring config,
-	 * declared as Spring beans. However since the standalone setup does not load
+	 * they need to be registered explicitly here instead much like controllers.
-	 * any Spring configuration they need to be registered explicitly here
-	 * instead much like controllers.
 	 * @since 4.2
 	 */
 	public StandaloneMockMvcBuilder setControllerAdvice(Object... controllerAdvice) {
-		Assert.isTrue(checkInstances(controllerAdvice), "ControllerAdvice instances are required");
+		this.controllerAdvice = instantiateIfNecessary(controllerAdvice);
-		this.controllerAdvice = Arrays.asList(controllerAdvice);
 		return this;
 	}
 
-	private boolean checkInstances(Object[] objects) {
-		return Arrays.stream(objects).noneMatch(Class.class::isInstance);
-	}
-
 	/**
 	 * Set the message converters to use in argument resolvers and in return value
 	 * handlers, which support reading and/or writing to the body of the request
@@ -405,7 +405,7 @@ public class StandaloneMockMvcBuilder extends AbstractMockMvcBuilder<StandaloneM
 
 	private List<ViewResolver> initViewResolvers(WebApplicationContext wac) {
 		this.viewResolvers = (this.viewResolvers != null ? this.viewResolvers :
-				Collections.<ViewResolver>singletonList(new InternalResourceViewResolver()));
+				Collections.singletonList(new InternalResourceViewResolver()));
 		for (Object viewResolver : this.viewResolvers) {
 			if (viewResolver instanceof WebApplicationObjectSupport) {
 				((WebApplicationObjectSupport) viewResolver).setApplicationContext(wac);
@@ -546,7 +546,7 @@ public class StandaloneMockMvcBuilder extends AbstractMockMvcBuilder<StandaloneM
 
 		@Override
 		@Nullable
-		public View resolveViewName(String viewName, Locale locale) throws Exception {
+		public View resolveViewName(String viewName, Locale locale) {
 			return this.view;
 		}
 	}

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

@@ -33,7 +33,7 @@ import org.springframework.web.reactive.config.PathMatchConfigurer;
 import org.springframework.web.reactive.config.ViewResolverRegistry;
 import org.springframework.web.reactive.result.method.annotation.ArgumentResolverConfigurer;
 
-import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.*;
 
 /**
  * Unit tests for {@link DefaultControllerSpec}.
@@ -63,19 +63,19 @@ public class DefaultControllerSpecTests {
 				.expectBody(String.class).isEqualTo("Handled exception");
 	}
 
-	@Test(expected = IllegalArgumentException.class)
+	@Test
-	public void controllerIsAnObjectInstance() {
+	public void controllerAdviceWithClassArgument() {
-		new DefaultControllerSpec(MyController.class);
+		new DefaultControllerSpec(MyController.class)
-	}
+				.controllerAdvice(MyControllerAdvice.class)
-
+				.build()
-	@Test(expected = IllegalArgumentException.class)
+				.get().uri("/exception")
-	public void controllerAdviceIsAnObjectInstance() {
+				.exchange()
-		new DefaultControllerSpec(new MyController()).controllerAdvice(MyControllerAdvice.class);
+				.expectStatus().isBadRequest()
+				.expectBody(String.class).isEqualTo("Handled exception");
 	}
 
 	@Test
 	public void configurerConsumers() {
-
 		TestConsumer<ArgumentResolverConfigurer> argumentResolverConsumer = new TestConsumer<>();
 		TestConsumer<RequestedContentTypeResolverBuilder> contenTypeResolverConsumer = new TestConsumer<>();
 		TestConsumer<CorsRegistry> corsRegistryConsumer = new TestConsumer<>();
@@ -104,6 +104,7 @@ public class DefaultControllerSpecTests {
 
 	}
 
+
 	@RestController
 	private static class MyController {
 
@@ -119,6 +120,7 @@ public class DefaultControllerSpecTests {
 
 	}
 
+
 	@ControllerAdvice
 	private static class MyControllerAdvice {
 
@@ -128,11 +130,11 @@ public class DefaultControllerSpecTests {
 		}
 	}
 
+
 	private static class TestConsumer<T> implements Consumer<T> {
 
 		private T value;
 
-
 		public T getValue() {
 			return this.value;
 		}

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -26,7 +26,6 @@ import com.gargoylesoftware.htmlunit.WebConnection;
 import com.gargoylesoftware.htmlunit.WebRequest;
 import com.gargoylesoftware.htmlunit.WebResponse;
 import com.gargoylesoftware.htmlunit.WebResponseData;
-import com.gargoylesoftware.htmlunit.util.NameValuePair;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -82,7 +81,7 @@ public class DelegatingWebConnectionTests {
 	@Before
 	public void setup() throws Exception {
 		request = new WebRequest(new URL("http://localhost/"));
-		WebResponseData data = new WebResponseData("".getBytes("UTF-8"), 200, "", Collections.<NameValuePair> emptyList());
+		WebResponseData data = new WebResponseData("".getBytes("UTF-8"), 200, "", Collections.emptyList());
 		expectedResponse = new WebResponse(data, request, 100L);
 		webConnection = new DelegatingWebConnection(defaultConnection,
 				new DelegateWebConnection(matcher1, connection1), new DelegateWebConnection(matcher2, connection2));
@@ -132,14 +131,13 @@ public class DelegatingWebConnectionTests {
 
 		WebClient webClient = new WebClient();
 
-		MockMvc mockMvc = MockMvcBuilders.standaloneSetup(TestController.class).build();
+		MockMvc mockMvc = MockMvcBuilders.standaloneSetup().build();
 		MockMvcWebConnection mockConnection = new MockMvcWebConnection(mockMvc, webClient);
 
 		WebRequestMatcher cdnMatcher = new UrlRegexRequestMatcher(".*?//code.jquery.com/.*");
 		WebConnection httpConnection = new HttpWebConnection(webClient);
-		WebConnection webConnection = new DelegatingWebConnection(mockConnection, new DelegateWebConnection(cdnMatcher, httpConnection));
+		webClient.setWebConnection(
-
+				new DelegatingWebConnection(mockConnection, new DelegateWebConnection(cdnMatcher, httpConnection)));
-		webClient.setWebConnection(webConnection);
 
 		Page page = webClient.getPage("http://code.jquery.com/jquery-1.11.0.min.js");
 		assertThat(page.getWebResponse().getStatusCode(), equalTo(200));

spring-test/src/test/java/org/springframework/test/web/servlet/samples/standalone/ExceptionHandlerTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -16,10 +16,6 @@
 
 package org.springframework.test.web.servlet.samples.standalone;
 
-import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
-import static org.springframework.test.web.servlet.setup.MockMvcBuilders.*;
-
 import org.junit.Test;
 
 import org.springframework.stereotype.Controller;
@@ -29,6 +25,10 @@ import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
+import static org.springframework.test.web.servlet.setup.MockMvcBuilders.*;
+
 /**
  * Exception handling via {@code @ExceptionHandler} method.
  *
@@ -36,7 +36,6 @@ import org.springframework.web.bind.annotation.RequestMethod;
  */
 public class ExceptionHandlerTests {
 
-
 	@Test
 	public void testExceptionHandlerMethod() throws Exception {
 		standaloneSetup(new PersonController()).build()
@@ -53,6 +52,14 @@ public class ExceptionHandlerTests {
 				.andExpect(forwardedUrl("globalErrorView"));
 	}
 
+	@Test
+	public void testGlobalExceptionHandlerMethodUsingClassArgument() throws Exception {
+		standaloneSetup(PersonController.class).setControllerAdvice(GlobalExceptionHandler.class).build()
+				.perform(get("/person/Bonnie"))
+				.andExpect(status().isOk())
+				.andExpect(forwardedUrl("globalErrorView"));
+	}
+
 
 	@Controller
 	private static class PersonController {
@@ -74,6 +81,7 @@ public class ExceptionHandlerTests {
 		}
 	}
 
+
 	@ControllerAdvice
 	private static class GlobalExceptionHandler {
 

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

@@ -43,7 +43,7 @@ import static org.junit.Assert.*;
 /**
  * Tests for {@link StandaloneMockMvcBuilder}
  *
- * @author Rossen
+ * @author Rossen Stoyanchev
  * @author Rob Winch
  * @author Sebastien Deleuze
  */
@@ -87,8 +87,7 @@ public class StandaloneMockMvcBuilderTests {
 		TestStandaloneMockMvcBuilder builder = new TestStandaloneMockMvcBuilder(new PlaceholderController());
 		builder.addPlaceholderValue("sys.login.ajax", "/foo");
 		WebApplicationContext  wac = builder.initWebAppContext();
-		assertEquals(wac, WebApplicationContextUtils
+		assertEquals(wac, WebApplicationContextUtils.getRequiredWebApplicationContext(wac.getServletContext()));
-				.getRequiredWebApplicationContext(wac.getServletContext()));
 	}
 
 	@Test(expected = IllegalArgumentException.class)
@@ -125,17 +124,6 @@ public class StandaloneMockMvcBuilderTests {
 		assertNotNull(serializer);
 	}
 
-	@Test(expected = IllegalArgumentException.class)
-	public void controllerIsAnObjectInstance() {
-		new StandaloneMockMvcBuilder(PersonController.class);
-	}
-
-	@Test(expected = IllegalArgumentException.class)
-	public void controllerAdviceIsAnObjectInstance() {
-		new StandaloneMockMvcBuilder(new PersonController()).setControllerAdvice(PersonController.class);
-	}
-
-
 
 	@Controller
 	private static class PlaceholderController {