Polishing

spring-messaging/src/main/java/org/springframework/messaging/simp/config/AbstractMessageBrokerConfiguration.java

@@ -433,7 +433,7 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 				catch (Throwable ex) {
 					throw new BeanInitializationException("Could not find default validator class", ex);
 				}
-				validator = (Validator) BeanUtils.instantiate(clazz);
+				validator = (Validator) BeanUtils.instantiateClass(clazz);
 			}
 			else {
 				validator = new Validator() {

spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/DelegatingWebMvcConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -22,6 +22,7 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.format.FormatterRegistry;
 import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.util.CollectionUtils;
 import org.springframework.validation.MessageCodesResolver;
 import org.springframework.validation.Validator;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
@@ -29,7 +30,7 @@ import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
 import org.springframework.web.servlet.HandlerExceptionResolver;
 
 /**
- * A sub-class of {@code WebMvcConfigurationSupport} that detects and delegates
+ * A subclass of {@code WebMvcConfigurationSupport} that detects and delegates
  * to all beans of type {@link WebMvcConfigurer} allowing them to customize the
  * configuration provided by {@code WebMvcConfigurationSupport}. This is the
  * class actually imported by {@link EnableWebMvc @EnableWebMvc}.
@@ -45,11 +46,10 @@ public class DelegatingWebMvcConfiguration extends WebMvcConfigurationSupport {
 
 	@Autowired(required = false)
 	public void setConfigurers(List<WebMvcConfigurer> configurers) {
-		if (configurers == null || configurers.isEmpty()) {
+		if (!CollectionUtils.isEmpty(configurers)) {
-			return;
-		}
 			this.configurers.addWebMvcConfigurers(configurers);
 		}
+	}
 
 
 	@Override
@@ -118,23 +118,23 @@ public class DelegatingWebMvcConfiguration extends WebMvcConfigurationSupport {
 	}
 
 	@Override
-	protected Validator getValidator() {
+	protected void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> exceptionResolvers) {
-		return this.configurers.getValidator();
+		this.configurers.configureHandlerExceptionResolvers(exceptionResolvers);
 	}
 
 	@Override
-	protected MessageCodesResolver getMessageCodesResolver() {
+	protected void addCorsMappings(CorsRegistry registry) {
-		return this.configurers.getMessageCodesResolver();
+		this.configurers.addCorsMappings(registry);
 	}
 
 	@Override
-	protected void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> exceptionResolvers) {
+	protected Validator getValidator() {
-		this.configurers.configureHandlerExceptionResolvers(exceptionResolvers);
+		return this.configurers.getValidator();
 	}
 
 	@Override
-	protected void addCorsMappings(CorsRegistry registry) {
+	protected MessageCodesResolver getMessageCodesResolver() {
-		this.configurers.addCorsMappings(registry);
+		return this.configurers.getMessageCodesResolver();
 	}
 
 }

spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/WebMvcConfigurationSupport.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -17,6 +17,7 @@
 package org.springframework.web.servlet.config.annotation;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
@@ -229,6 +230,7 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 		return this.servletContext;
 	}
 
+
 	/**
 	 * Return a {@link RequestMappingHandlerMapping} ordered at 0 for mapping
 	 * requests to annotated controllers.
@@ -251,18 +253,20 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 		if (configurer.isUseTrailingSlashMatch() != null) {
 			handlerMapping.setUseTrailingSlashMatch(configurer.isUseTrailingSlashMatch());
 		}
-		if (configurer.getPathMatcher() != null) {
+		UrlPathHelper pathHelper = configurer.getUrlPathHelper();
-			handlerMapping.setPathMatcher(configurer.getPathMatcher());
+		if (pathHelper != null) {
+			handlerMapping.setUrlPathHelper(pathHelper);
 		}
-		if (configurer.getUrlPathHelper() != null) {
+		PathMatcher pathMatcher = configurer.getPathMatcher();
-			handlerMapping.setUrlPathHelper(configurer.getUrlPathHelper());
+		if (pathMatcher != null) {
+			handlerMapping.setPathMatcher(pathMatcher);
 		}
 
 		return handlerMapping;
 	}
 
 	/**
-	 * Protected method for plugging in a custom sub-class of
+	 * Protected method for plugging in a custom subclass of
 	 * {@link RequestMappingHandlerMapping}.
 	 */
 	protected RequestMappingHandlerMapping createRequestMappingHandlerMapping() {
@@ -335,7 +339,7 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 	}
 
 	protected Map<String, MediaType> getDefaultMediaTypes() {
-		Map<String, MediaType> map = new HashMap<String, MediaType>();
+		Map<String, MediaType> map = new HashMap<String, MediaType>(4);
 		if (romePresent) {
 			map.put("atom", MediaType.APPLICATION_ATOM_XML);
 			map.put("rss", MediaType.valueOf("application/rss+xml"));
@@ -488,18 +492,14 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 		adapter.setCustomReturnValueHandlers(returnValueHandlers);
 
 		if (jackson2Present) {
-			List<RequestBodyAdvice> requestBodyAdvices = new ArrayList<RequestBodyAdvice>();
+			adapter.setRequestBodyAdvice(
-			requestBodyAdvices.add(new JsonViewRequestBodyAdvice());
+					Collections.<RequestBodyAdvice>singletonList(new JsonViewRequestBodyAdvice()));
-			adapter.setRequestBodyAdvice(requestBodyAdvices);
+			adapter.setResponseBodyAdvice(
-
+					Collections.<ResponseBodyAdvice<?>>singletonList(new JsonViewResponseBodyAdvice()));
-			List<ResponseBodyAdvice<?>> responseBodyAdvices = new ArrayList<ResponseBodyAdvice<?>>();
-			responseBodyAdvices.add(new JsonViewResponseBodyAdvice());
-			adapter.setResponseBodyAdvice(responseBodyAdvices);
 		}
 
 		AsyncSupportConfigurer configurer = new AsyncSupportConfigurer();
 		configureAsyncSupport(configurer);
-
 		if (configurer.getTaskExecutor() != null) {
 			adapter.setTaskExecutor(configurer.getTaskExecutor());
 		}
@@ -524,6 +524,20 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 		return initializer;
 	}
 
+	/**
+	 * Override this method to provide a custom {@link MessageCodesResolver}.
+	 */
+	protected MessageCodesResolver getMessageCodesResolver() {
+		return null;
+	}
+
+	/**
+	 * Override this method to configure asynchronous request processing options.
+	 * @see AsyncSupportConfigurer
+	 */
+	protected void configureAsyncSupport(AsyncSupportConfigurer configurer) {
+	}
+
 	/**
 	 * Return a {@link FormattingConversionService} for use with annotated
 	 * controller methods and the {@code spring:eval} JSP tag.
@@ -536,6 +550,12 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 		return conversionService;
 	}
 
+	/**
+	 * Override this method to add custom {@link Converter}s and {@link Formatter}s.
+	 */
+	protected void addFormatters(FormatterRegistry registry) {
+	}
+
 	/**
 	 * Return a global {@link Validator} instance for example for validating
 	 * {@code @ModelAttribute} and {@code @RequestBody} method arguments.
@@ -560,7 +580,7 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 				catch (LinkageError ex) {
 					throw new BeanInitializationException("Could not load default validator class", ex);
 				}
-				validator = (Validator) BeanUtils.instantiate(clazz);
+				validator = (Validator) BeanUtils.instantiateClass(clazz);
 			}
 			else {
 				validator = new NoOpValidator();
@@ -569,6 +589,13 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 		return validator;
 	}
 
+	/**
+	 * Override this method to provide a custom {@link Validator}.
+	 */
+	protected Validator getValidator() {
+		return null;
+	}
+
 	/**
 	 * Return a global {@link PathMatcher} instance for path matching
 	 * patterns in {@link HandlerMapping}s.
@@ -595,26 +622,8 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 	 */
 	@Bean
 	public UrlPathHelper mvcUrlPathHelper() {
-		if (getPathMatchConfigurer().getUrlPathHelper() != null) {
+		UrlPathHelper pathHelper = getPathMatchConfigurer().getUrlPathHelper();
-			return getPathMatchConfigurer().getUrlPathHelper();
+		return (pathHelper != null ? pathHelper : new UrlPathHelper());
-		}
-		else {
-			return new UrlPathHelper();
-		}
-	}
-
-	/**
-	 * Override this method to provide a custom {@link Validator}.
-	 */
-	protected Validator getValidator() {
-		return null;
-	}
-
-	/**
-	 * Override this method to provide a custom {@link MessageCodesResolver}.
-	 */
-	protected MessageCodesResolver getMessageCodesResolver() {
-		return null;
 	}
 
 	/**
@@ -679,6 +688,14 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 	protected void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
 	}
 
+	/**
+	 * Override this method to extend or modify the list of converters after it
+	 * has been configured. This may be useful for example to allow default
+	 * converters to be registered and then insert a custom converter through
+	 * this method.
+	 * @param converters the list of configured converters to extend.
+	 * @since 4.1.3
+	 */
 	protected void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
 	}
 
@@ -719,19 +736,6 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 		}
 	}
 
-	/**
-	 * Override this method to add custom {@link Converter}s and {@link Formatter}s.
-	 */
-	protected void addFormatters(FormatterRegistry registry) {
-	}
-
-	/**
-	 * Override this method to configure asynchronous request processing options.
-	 * @see AsyncSupportConfigurer
-	 */
-	public void configureAsyncSupport(AsyncSupportConfigurer configurer) {
-	}
-
 	/**
 	 * Return an instance of {@link CompositeUriComponentsContributor} for use with
 	 * {@link org.springframework.web.servlet.mvc.method.annotation.MvcUriComponentsBuilder}.
@@ -774,11 +778,9 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 	public HandlerExceptionResolver handlerExceptionResolver() {
 		List<HandlerExceptionResolver> exceptionResolvers = new ArrayList<HandlerExceptionResolver>();
 		configureHandlerExceptionResolvers(exceptionResolvers);
-
 		if (exceptionResolvers.isEmpty()) {
 			addDefaultHandlerExceptionResolvers(exceptionResolvers);
 		}
-
 		HandlerExceptionResolverComposite composite = new HandlerExceptionResolverComposite();
 		composite.setOrder(0);
 		composite.setExceptionResolvers(exceptionResolvers);

spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/WebMvcConfigurer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -73,14 +73,6 @@ public interface WebMvcConfigurer {
 	 */
 	void extendMessageConverters(List<HttpMessageConverter<?>> converters);
 
-	/**
-	 * Provide a custom {@link Validator} instead of the one created by default.
-	 * The default implementation, assuming JSR-303 is on the classpath, is:
-	 * {@link org.springframework.validation.beanvalidation.OptionalValidatorFactoryBean}.
-	 * Leave the return value as {@code null} to keep the default.
-	 */
-	Validator getValidator();
-
 	/**
 	 * Configure content negotiation options.
 	 */
@@ -144,13 +136,6 @@ public interface WebMvcConfigurer {
 	 */
 	void addInterceptors(InterceptorRegistry registry);
 
-	/**
-	 * Provide a custom {@link MessageCodesResolver} for building message codes
-	 * from data binding and validation error codes. Leave the return value as
-	 * {@code null} to keep the default.
-	 */
-	MessageCodesResolver getMessageCodesResolver();
-
 	/**
 	 * Configure simple automated controllers pre-configured with the response
 	 * status code and/or a view to render the response body. This is useful in
@@ -188,4 +173,19 @@ public interface WebMvcConfigurer {
 	 */
 	void addCorsMappings(CorsRegistry registry);
 
+	/**
+	 * Provide a custom {@link Validator} instead of the one created by default.
+	 * The default implementation, assuming JSR-303 is on the classpath, is:
+	 * {@link org.springframework.validation.beanvalidation.OptionalValidatorFactoryBean}.
+	 * Leave the return value as {@code null} to keep the default.
+	 */
+	Validator getValidator();
+
+	/**
+	 * Provide a custom {@link MessageCodesResolver} for building message codes
+	 * from data binding and validation error codes. Leave the return value as
+	 * {@code null} to keep the default.
+	 */
+	MessageCodesResolver getMessageCodesResolver();
+
 }

spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/WebMvcConfigurerAdapter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -28,7 +28,7 @@ import org.springframework.web.servlet.HandlerExceptionResolver;
 
 /**
  * An implementation of {@link WebMvcConfigurer} with empty methods allowing
- * sub-classes to override only the methods they're interested in.
+ * subclasses to override only the methods they're interested in.
  *
  * @author Rossen Stoyanchev
  * @since 3.1
@@ -59,15 +59,6 @@ public abstract class WebMvcConfigurerAdapter implements WebMvcConfigurer {
 	public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
 	}
 
-	/**
-	 * {@inheritDoc}
-	 * <p>This implementation returns {@code null}
-	 */
-	@Override
-	public Validator getValidator() {
-		return null;
-	}
-
 	/**
 	 * {@inheritDoc}
 	 * <p>This implementation is empty.
@@ -116,15 +107,6 @@ public abstract class WebMvcConfigurerAdapter implements WebMvcConfigurer {
 	public void configureHandlerExceptionResolvers(List<HandlerExceptionResolver> exceptionResolvers) {
 	}
 
-	/**
-	 * {@inheritDoc}
-	 * <p>This implementation is empty.
-	 */
-	@Override
-	public MessageCodesResolver getMessageCodesResolver() {
-		return null;
-	}
-
 	/**
 	 * {@inheritDoc}
 	 * <p>This implementation is empty.
@@ -173,4 +155,22 @@ public abstract class WebMvcConfigurerAdapter implements WebMvcConfigurer {
 	public void addCorsMappings(CorsRegistry registry) {
 	}
 
+	/**
+	 * {@inheritDoc}
+	 * <p>This implementation returns {@code null}.
+	 */
+	@Override
+	public Validator getValidator() {
+		return null;
+	}
+
+	/**
+	 * {@inheritDoc}
+	 * <p>This implementation returns {@code null}.
+	 */
+	@Override
+	public MessageCodesResolver getMessageCodesResolver() {
+		return null;
+	}
+
 }

spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/WebMvcConfigurerComposite.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -21,6 +21,7 @@ import java.util.List;
 
 import org.springframework.format.FormatterRegistry;
 import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.util.CollectionUtils;
 import org.springframework.validation.MessageCodesResolver;
 import org.springframework.validation.Validator;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
@@ -28,7 +29,7 @@ import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
 import org.springframework.web.servlet.HandlerExceptionResolver;
 
 /**
- * An {@link WebMvcConfigurer} implementation that delegates to other {@link WebMvcConfigurer} instances.
+ * A {@link WebMvcConfigurer} that delegates to one or more others.
  *
  * @author Rossen Stoyanchev
  * @since 3.1
@@ -37,12 +38,14 @@ class WebMvcConfigurerComposite implements WebMvcConfigurer {
 
 	private final List<WebMvcConfigurer> delegates = new ArrayList<WebMvcConfigurer>();
 
+
 	public void addWebMvcConfigurers(List<WebMvcConfigurer> configurers) {
-		if (configurers != null) {
+		if (!CollectionUtils.isEmpty(configurers)) {
 			this.delegates.addAll(configurers);
 		}
 	}
 
+
 	@Override
 	public void addFormatters(FormatterRegistry registry) {
 		for (WebMvcConfigurer delegate : this.delegates) {
@@ -141,6 +144,13 @@ class WebMvcConfigurerComposite implements WebMvcConfigurer {
 		}
 	}
 
+	@Override
+	public void addCorsMappings(CorsRegistry registry) {
+		for (WebMvcConfigurer delegate : this.delegates) {
+			delegate.addCorsMappings(registry);
+		}
+	}
+
 	@Override
 	public Validator getValidator() {
 		List<Validator> candidates = new ArrayList<Validator>();
@@ -154,11 +164,16 @@ class WebMvcConfigurerComposite implements WebMvcConfigurer {
 	}
 
 	@Override
-	public void addCorsMappings(CorsRegistry registry) {
+	public MessageCodesResolver getMessageCodesResolver() {
-		for (WebMvcConfigurer delegate : this.delegates) {
+		List<MessageCodesResolver> candidates = new ArrayList<MessageCodesResolver>();
-			delegate.addCorsMappings(registry);
+		for (WebMvcConfigurer configurer : this.delegates) {
+			MessageCodesResolver messageCodesResolver = configurer.getMessageCodesResolver();
+			if (messageCodesResolver != null) {
+				candidates.add(messageCodesResolver);
 			}
 		}
+		return selectSingleInstance(candidates, MessageCodesResolver.class);
+	}
 
 	private <T> T selectSingleInstance(List<T> instances, Class<T> instanceType) {
 		if (instances.size() > 1) {
@@ -173,16 +188,4 @@ class WebMvcConfigurerComposite implements WebMvcConfigurer {
 		}
 	}
 
-	@Override
-	public MessageCodesResolver getMessageCodesResolver() {
-		List<MessageCodesResolver> candidates = new ArrayList<MessageCodesResolver>();
-		for (WebMvcConfigurer configurer : this.delegates) {
-			MessageCodesResolver messageCodesResolver = configurer.getMessageCodesResolver();
-			if (messageCodesResolver != null) {
-				candidates.add(messageCodesResolver);
-			}
-		}
-		return selectSingleInstance(candidates, MessageCodesResolver.class);
-	}
-
 }

spring-webmvc/src/test/java/org/springframework/web/servlet/config/annotation/DelegatingWebMvcConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -17,7 +17,7 @@
 package org.springframework.web.servlet.config.annotation;
 
 import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 
 import org.junit.Before;
@@ -89,10 +89,10 @@ public class DelegatingWebMvcConfigurationTests {
 		delegatingConfig = new DelegatingWebMvcConfiguration();
 	}
 
+
 	@Test
 	public void requestMappingHandlerAdapter() throws Exception {
-
+		delegatingConfig.setConfigurers(Collections.singletonList(webMvcConfigurer));
-		delegatingConfig.setConfigurers(Arrays.asList(webMvcConfigurer));
 		RequestMappingHandlerAdapter adapter = delegatingConfig.requestMappingHandlerAdapter();
 
 		ConfigurableWebBindingInitializer initializer = (ConfigurableWebBindingInitializer) adapter.getWebBindingInitializer();
@@ -141,7 +141,7 @@ public class DelegatingWebMvcConfigurationTests {
 	public void getCustomValidator() {
 		given(webMvcConfigurer.getValidator()).willReturn(new LocalValidatorFactoryBean());
 
-		delegatingConfig.setConfigurers(Arrays.asList(webMvcConfigurer));
+		delegatingConfig.setConfigurers(Collections.singletonList(webMvcConfigurer));
 		delegatingConfig.mvcValidator();
 
 		verify(webMvcConfigurer).getValidator();
@@ -151,7 +151,7 @@ public class DelegatingWebMvcConfigurationTests {
 	public void getCustomMessageCodesResolver() {
 		given(webMvcConfigurer.getMessageCodesResolver()).willReturn(new DefaultMessageCodesResolver());
 
-		delegatingConfig.setConfigurers(Arrays.asList(webMvcConfigurer));
+		delegatingConfig.setConfigurers(Collections.singletonList(webMvcConfigurer));
 		delegatingConfig.getMessageCodesResolver();
 
 		verify(webMvcConfigurer).getMessageCodesResolver();
@@ -159,8 +159,7 @@ public class DelegatingWebMvcConfigurationTests {
 
 	@Test
 	public void handlerExceptionResolver() throws Exception {
-
+		delegatingConfig.setConfigurers(Collections.singletonList(webMvcConfigurer));
-		delegatingConfig.setConfigurers(Arrays.asList(webMvcConfigurer));
 		delegatingConfig.handlerExceptionResolver();
 
 		verify(webMvcConfigurer).configureMessageConverters(converters.capture());