SPR-6788 - The class MediaType has a natural ordering that is inconsistent with equals, which is generally recommended or should otherwise at least be indicated in the javadoc

git-svn-id: https://src.springframework.org/svn/spring-framework/trunk@2900 50f2f4bb-b051-0410-bef5-90022cba6387

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/mvc/annotation/AnnotationMethodHandlerAdapter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2010 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.
@@ -864,9 +864,7 @@ public class AnnotationMethodHandlerAdapter extends WebContentGenerator
 			if (acceptedMediaTypes.isEmpty()) {
 				acceptedMediaTypes = Collections.singletonList(MediaType.ALL);
 			}
-			else {
-				Collections.sort(acceptedMediaTypes);
-			}
+			MediaType.sortBySpecificity(acceptedMediaTypes);
 			HttpOutputMessage outputMessage = new ServletServerHttpResponse(webRequest.getResponse());
 			Class<?> returnValueType = returnValue.getClass();
 			List<MediaType> allSupportedMediaTypes = new ArrayList<MediaType>();

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/view/ContentNegotiatingViewResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2010 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.
@@ -33,6 +33,9 @@ import javax.servlet.ServletContext;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
 import org.springframework.beans.factory.BeanFactoryUtils;
 import org.springframework.core.OrderComparator;
 import org.springframework.core.Ordered;
@@ -100,6 +103,8 @@ import org.springframework.web.util.WebUtils;
  */
 public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport implements ViewResolver, Ordered {
 
+	private static final Log logger = LogFactory.getLog(ContentNegotiatingViewResolver.class);
+
 	private static final String ACCEPT_HEADER = "Accept";
 
 	private static final boolean jafPresent =
@@ -267,9 +272,7 @@ public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport
 				if (logger.isDebugEnabled()) {
 					logger.debug("Requested media type is '" + mediaType + "' (based on filename '" + filename + "')");
 				}
-				List<MediaType> mediaTypes = new ArrayList<MediaType>();
-				mediaTypes.add(mediaType);
-				return mediaTypes;
+				return Collections.singletonList(mediaType);
 			}
 		}
 		if (this.favorParameter) {
@@ -281,9 +284,7 @@ public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport
 						logger.debug("Requested media type is '" + mediaType + "' (based on parameter '" +
 								this.parameterName + "'='" + parameterValue + "')");
 					}
-					List<MediaType> mediaTypes = new ArrayList<MediaType>();
-					mediaTypes.add(mediaType);
-					return mediaTypes;
+					return Collections.singletonList(mediaType);
 				}
 			}
 		}
@@ -291,6 +292,7 @@ public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport
 			String acceptHeader = request.getHeader(ACCEPT_HEADER);
 			if (StringUtils.hasText(acceptHeader)) {
 				List<MediaType> mediaTypes = MediaType.parseMediaTypes(acceptHeader);
+				MediaType.sortBySpecificity(mediaTypes);
 				if (logger.isDebugEnabled()) {
 					logger.debug("Requested media types are " + mediaTypes + " (based on Accept header)");
 				}
@@ -298,6 +300,9 @@ public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport
 			}
 		}
 		if (this.defaultContentType != null) {
+			if (logger.isDebugEnabled()) {
+				logger.debug("Requested media types is " + defaultContentType + " (based on defaultContentType property)");
+			}
 			return Collections.singletonList(this.defaultContentType);
 		}
 		else {
@@ -348,10 +353,6 @@ public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport
 		ServletRequestAttributes servletAttrs = (ServletRequestAttributes) attrs;
 
 		List<MediaType> requestedMediaTypes = getMediaTypes(servletAttrs.getRequest());
-		if (requestedMediaTypes.size() > 1) {
-			// avoid sorting attempt for empty list and singleton list
-			Collections.sort(requestedMediaTypes);
-		}
 
 		List<View> candidateViews = new ArrayList<View>();
 		for (ViewResolver viewResolver : this.viewResolvers) {
@@ -364,32 +365,44 @@ public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport
 			candidateViews.addAll(this.defaultViews);
 		}
 
-		SortedMap<MediaType, View> views = new TreeMap<MediaType, View>();
-		for (View candidateView : candidateViews) {
-			String contentType = candidateView.getContentType();
-			if (StringUtils.hasText(contentType)) {
-				MediaType viewMediaType = MediaType.parseMediaType(contentType);
-				for (MediaType requestedMediaType : requestedMediaTypes) {
-					if (requestedMediaType.includes(viewMediaType)) {
-						if (!views.containsKey(requestedMediaType)) {
-							views.put(requestedMediaType, candidateView);
-							break;
-						}
+		MediaType bestRequestedMediaType = null;
+		View bestView = null;
+		for (MediaType requestedMediaType : requestedMediaTypes) {
+			for (View candidateView : candidateViews) {
+				if (StringUtils.hasText(candidateView.getContentType())) {
+					MediaType candidateContentType = MediaType.parseMediaType(candidateView.getContentType());
+					if (requestedMediaType.includes(candidateContentType)) {
+						bestRequestedMediaType = requestedMediaType;
+						bestView = candidateView;
+						break;
 					}
 				}
 			}
+			if (bestView != null) {
+				break;
+			}
 		}
 
-		if (!views.isEmpty()) {
-			MediaType mediaType = views.firstKey();
-			View view = views.get(mediaType);
+		if (bestView != null) {
 			if (logger.isDebugEnabled()) {
-				logger.debug("Returning [" + view + "] based on requested media type '" + mediaType + "'");
+				logger.debug("Returning [" + bestView + "] based on requested media type '" +
+						bestRequestedMediaType + "'");
 			}
-			return view;
+			return bestView;
 		}
 		else {
-			return useNotAcceptableStatusCode ? new NotAcceptableView() : null;
+			if (useNotAcceptableStatusCode) {
+				if (logger.isDebugEnabled()) {
+					logger.debug("No acceptable view found; returning 406 (Not Acceptable) status code");
+				}
+				return NOT_ACCEPTABLE_VIEW;
+			}
+			else {
+				if (logger.isDebugEnabled()) {
+					logger.debug("No acceptable view found; returning null");
+				}
+				return null;
+			}
 		}
 	}
 
@@ -408,6 +421,9 @@ public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport
 			// see if we can find the extended mime.types from the context-support module
 			Resource mappingLocation = new ClassPathResource("org/springframework/mail/javamail/mime.types");
 			if (mappingLocation.exists()) {
+				if (logger.isTraceEnabled()) {
+					logger.trace("Loading Java Activation Framework FileTypeMap from " + mappingLocation);
+				}
 				InputStream inputStream = null;
 				try {
 					inputStream = mappingLocation.getInputStream();
@@ -427,6 +443,9 @@ public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport
 					}
 				}
 			}
+			if (logger.isTraceEnabled()) {
+				logger.trace("Loading default Java Activation Framework FileTypeMap");
+			}
 			return FileTypeMap.getDefaultFileTypeMap();
 		}
 
@@ -436,7 +455,7 @@ public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport
 		}
 	}
 
-	private static class NotAcceptableView implements View {
+	private static final View NOT_ACCEPTABLE_VIEW = new View() {
 
 		public String getContentType() {
 			return null;
@@ -446,5 +465,5 @@ public class ContentNegotiatingViewResolver extends WebApplicationObjectSupport
 				throws Exception {
 			response.setStatus(HttpServletResponse.SC_NOT_ACCEPTABLE);
 		}
-	}
+	};
 }

org.springframework.web.servlet/src/test/java/org/springframework/web/servlet/view/ContentNegotiatingViewResolverTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2010 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.
@@ -128,8 +128,8 @@ public class ContentNegotiatingViewResolverTests {
 
 		expect(viewResolverMock1.resolveViewName(viewName, locale)).andReturn(viewMock1);
 		expect(viewResolverMock2.resolveViewName(viewName, locale)).andReturn(viewMock2);
-		expect(viewMock1.getContentType()).andReturn("application/xml");
-		expect(viewMock2.getContentType()).andReturn("text/html;charset=ISO-8859-1");
+		expect(viewMock1.getContentType()).andReturn("application/xml").anyTimes();
+		expect(viewMock2.getContentType()).andReturn("text/html;charset=ISO-8859-1").anyTimes();
 
 		replay(viewResolverMock1, viewResolverMock2, viewMock1, viewMock2);
 
@@ -160,8 +160,8 @@ public class ContentNegotiatingViewResolverTests {
 
 		expect(viewResolverMock1.resolveViewName(viewName, locale)).andReturn(viewMock1);
 		expect(viewResolverMock2.resolveViewName(viewName, locale)).andReturn(viewMock2);
-		expect(viewMock1.getContentType()).andReturn("application/xml");
-		expect(viewMock2.getContentType()).andReturn("text/html;charset=ISO-8859-1");
+		expect(viewMock1.getContentType()).andReturn("application/xml").anyTimes();
+		expect(viewMock2.getContentType()).andReturn("text/html;charset=ISO-8859-1").anyTimes();
 
 		replay(viewResolverMock1, viewResolverMock2, viewMock1, viewMock2);
 
@@ -197,9 +197,9 @@ public class ContentNegotiatingViewResolverTests {
 
 		expect(viewResolverMock1.resolveViewName(viewName, locale)).andReturn(viewMock1);
 		expect(viewResolverMock2.resolveViewName(viewName, locale)).andReturn(viewMock2);
-		expect(viewMock1.getContentType()).andReturn("application/xml");
-		expect(viewMock2.getContentType()).andReturn("text/html;charset=ISO-8859-1");
-		expect(viewMock3.getContentType()).andReturn("application/json");
+		expect(viewMock1.getContentType()).andReturn("application/xml").anyTimes();
+		expect(viewMock2.getContentType()).andReturn("text/html;charset=ISO-8859-1").anyTimes();
+		expect(viewMock3.getContentType()).andReturn("application/json").anyTimes();
 
 		replay(viewResolverMock1, viewResolverMock2, viewMock1, viewMock2, viewMock3);
 
@@ -229,8 +229,8 @@ public class ContentNegotiatingViewResolverTests {
 
 		expect(viewResolverMock1.resolveViewName(viewName, locale)).andReturn(viewMock1);
 		expect(viewResolverMock2.resolveViewName(viewName, locale)).andReturn(viewMock2);
-		expect(viewMock1.getContentType()).andReturn("application/xml");
-		expect(viewMock2.getContentType()).andReturn("text/html;charset=ISO-8859-1");
+		expect(viewMock1.getContentType()).andReturn("application/xml").anyTimes();
+		expect(viewMock2.getContentType()).andReturn("text/html;charset=ISO-8859-1").anyTimes();
 
 		replay(viewResolverMock1, viewResolverMock2, viewMock1, viewMock2);
 
@@ -269,9 +269,9 @@ public class ContentNegotiatingViewResolverTests {
 
 		expect(viewResolverMock1.resolveViewName(viewName, locale)).andReturn(viewMock1);
 		expect(viewResolverMock2.resolveViewName(viewName, locale)).andReturn(viewMock2);
-		expect(viewMock1.getContentType()).andReturn("application/xml");
-		expect(viewMock2.getContentType()).andReturn("text/html;charset=ISO-8859-1");
-		expect(viewMock3.getContentType()).andReturn("application/json");
+		expect(viewMock1.getContentType()).andReturn("application/xml").anyTimes();
+		expect(viewMock2.getContentType()).andReturn("text/html;charset=ISO-8859-1").anyTimes();
+		expect(viewMock3.getContentType()).andReturn("application/json").anyTimes();
 
 		replay(viewResolverMock1, viewResolverMock2, viewMock1, viewMock2, viewMock3);
 
@@ -296,7 +296,7 @@ public class ContentNegotiatingViewResolverTests {
 		Locale locale = Locale.ENGLISH;
 
 		expect(viewResolverMock.resolveViewName(viewName, locale)).andReturn(viewMock);
-		expect(viewMock.getContentType()).andReturn(null);
+		expect(viewMock.getContentType()).andReturn(null).anyTimes();
 
 		replay(viewResolverMock, viewMock);
 
@@ -321,7 +321,7 @@ public class ContentNegotiatingViewResolverTests {
 		Locale locale = Locale.ENGLISH;
 
 		expect(viewResolverMock.resolveViewName(viewName, locale)).andReturn(viewMock);
-		expect(viewMock.getContentType()).andReturn("application/pdf");
+		expect(viewMock.getContentType()).andReturn("application/pdf").anyTimes();
 
 		replay(viewResolverMock, viewMock);
 
@@ -347,7 +347,7 @@ public class ContentNegotiatingViewResolverTests {
 		Locale locale = Locale.ENGLISH;
 
 		expect(viewResolverMock.resolveViewName(viewName, locale)).andReturn(viewMock);
-		expect(viewMock.getContentType()).andReturn("application/pdf");
+		expect(viewMock.getContentType()).andReturn("application/pdf").anyTimes();
 
 		replay(viewResolverMock, viewMock);
 

org.springframework.web/src/main/java/org/springframework/http/MediaType.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2010 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.
@@ -25,6 +25,7 @@ import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Comparator;
 
 import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
@@ -40,10 +41,10 @@ import org.springframework.util.StringUtils;
  *
  * @author Arjen Poutsma
  * @author Juergen Hoeller
- * @see <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.7">HTTP 1.1</a>
+ * @see <a href="http://tools.ietf.org/html/rfc2616#section-3.7">HTTP 1.1, section 3.7</a>
  * @since 3.0
  */
-public class MediaType implements Comparable<MediaType> {
+public class MediaType {
 
 	public static final MediaType ALL = new MediaType("*", "*");
 
@@ -60,8 +61,9 @@ public class MediaType implements Comparable<MediaType> {
 	private final Map<String, String> parameters;
 
 	/**
-	 * Create a new {@link MediaType} for the given primary type. <p>The {@linkplain #getSubtype() subtype} is set to
-	 * <code>&#42;</code>, parameters empty.
+	 * Create a new {@link MediaType} for the given primary type.
+	 *
+	 * <p>The {@linkplain #getSubtype() subtype} is set to <code>&#42;</code>, parameters empty.
 	 *
 	 * @param type the primary type
 	 */
@@ -90,6 +92,17 @@ public class MediaType implements Comparable<MediaType> {
 		this(type, subtype, Collections.singletonMap(PARAM_CHARSET, charSet.toString()));
 	}
 
+	/**
+	 * Create a new {@link MediaType} for the given type, subtype, and quality value.
+	 *
+	 * @param type the primary type
+	 * @param subtype the subtype
+	 * @param qualityValue the quality value
+	 */
+	public MediaType(String type, String subtype, double qualityValue) {
+		this(type, subtype, Collections.singletonMap(PARAM_QUALITY_FACTORY, Double.toString(qualityValue)));
+	}
+
 	/**
 	 * Create a new {@link MediaType} for the given type, subtype, and parameters.
 	 *
@@ -100,10 +113,12 @@ public class MediaType implements Comparable<MediaType> {
 	public MediaType(String type, String subtype, Map<String, String> parameters) {
 		Assert.hasText(type, "'type' must not be empty");
 		Assert.hasText(subtype, "'subtype' must not be empty");
+		Assert.doesNotContain(type, "/", "'type' must not contain /");
+		Assert.doesNotContain(subtype, "/", "'subtype' must not contain /");
 		this.type = type.toLowerCase(Locale.ENGLISH);
 		this.subtype = subtype.toLowerCase(Locale.ENGLISH);
 		if (!CollectionUtils.isEmpty(parameters)) {
-			this.parameters = new LinkedCaseInsensitiveMap<String>(parameters.size());
+			this.parameters = new LinkedCaseInsensitiveMap<String>(parameters.size(), Locale.ENGLISH);
 			this.parameters.putAll(parameters);
 		}
 		else {
@@ -141,7 +156,7 @@ public class MediaType implements Comparable<MediaType> {
 	 * @return the character set; or <code>null</code> if not available
 	 */
 	public Charset getCharSet() {
-		String charSet = this.parameters.get(PARAM_CHARSET);
+		String charSet = getParameter(PARAM_CHARSET);
 		return (charSet != null ? Charset.forName(charSet) : null);
 	}
 
@@ -151,7 +166,7 @@ public class MediaType implements Comparable<MediaType> {
 	 * @return the quality factory
 	 */
 	public double getQualityValue() {
-		String qualityFactory = this.parameters.get(PARAM_QUALITY_FACTORY);
+		String qualityFactory = getParameter(PARAM_QUALITY_FACTORY);
 		return (qualityFactory != null ? Double.parseDouble(qualityFactory) : 1D);
 	}
 
@@ -166,8 +181,10 @@ public class MediaType implements Comparable<MediaType> {
 	}
 
 	/**
-	 * Indicate whether this {@link MediaType} includes the given media type. <p>For instance, {@code text/*} includes
-	 * {@code text/plain}, {@code text/html}, and {@code application/*+xml} includes {@code application/soap+xml}, etc.
+	 * Indicate whether this {@link MediaType} includes the given media type.
+	 *
+	 * <p>For instance, {@code text/*} includes {@code text/plain}, {@code text/html}, and {@code application/*+xml}
+	 * includes {@code application/soap+xml}, etc.
 	 *
 	 * @param other the reference media type with which to compare
 	 * @return <code>true</code> if this media type includes the given media type; <code>false</code> otherwise
@@ -196,51 +213,6 @@ public class MediaType implements Comparable<MediaType> {
 		return isWildcardType();
 	}
 
-	/**
-	 * Compare this {@link MediaType} to another. Sorting with this comparator follows the general rule: <blockquote>
-	 * audio/basic &lt; audio/* &lt; *&#047;* </blockquote>. That is, an explicit media type is sorted before an unspecific
-	 * media type. Quality parameters are also considered, so that <blockquote> audio/* &lt; audio/*;q=0.7;
-	 * audio/*;q=0.3</blockquote>.
-	 *
-	 * @param other the media type to compare to
-	 * @return a negative integer, zero, or a positive integer as this media type is less than, equal to, or greater than
-	 *         the specified media type
-	 */
-	public int compareTo(MediaType other) {
-		double qVal1 = this.getQualityValue();
-		double qVal2 = other.getQualityValue();
-		int qComp = Double.compare(qVal2, qVal1);
-		if (qComp != 0) {
-			return qComp;
-		}
-		else if (this.isWildcardType() && !other.isWildcardType()) {
-			return 1;
-		}
-		else if (other.isWildcardType() && !this.isWildcardType()) {
-			return -1;
-		}
-		else if (!this.getType().equals(other.getType())) {
-			return this.getType().compareTo(other.getType());
-		}
-		else { // mediaType1.getType().equals(mediaType2.getType())
-			if (this.isWildcardSubtype() && !other.isWildcardSubtype()) {
-				return 1;
-			}
-			else if (other.isWildcardSubtype() && !this.isWildcardSubtype()) {
-				return -1;
-			}
-			else if (!this.getSubtype().equals(other.getSubtype())) {
-				return this.getSubtype().compareTo(other.getSubtype());
-			}
-			else { // mediaType2.getSubtype().equals(mediaType2.getSubtype())
-				double quality1 = this.getQualityValue();
-				double quality2 = other.getQualityValue();
-				return Double.compare(quality2, quality1);
-			}
-		}
-
-	}
-
 	@Override
 	public boolean equals(Object other) {
 		if (this == other) {
@@ -339,8 +311,9 @@ public class MediaType implements Comparable<MediaType> {
 	}
 
 	/**
-	 * Return a string representation of the given list of {@link MediaType} objects. <p>This method can be used to for an
-	 * Accept or Content-Type header.
+	 * Return a string representation of the given list of {@link MediaType} objects.
+	 *
+	 * <p>This method can be used to for an {@code Accept} or {@code Content-Type} header.
 	 *
 	 * @param mediaTypes the string to parse
 	 * @return the list of media types
@@ -358,4 +331,78 @@ public class MediaType implements Comparable<MediaType> {
 		return builder.toString();
 	}
 
+	/**
+	 * Sorts the given list of {@link MediaType} objects by specificity.
+	 *
+	 * <p>Given two media types:
+	 * <ol>
+	 *   <li>if either media type has a {@linkplain #isWildcardType() wildcard type}, then the media type without the
+	 *   wildcard is ordered before the other.</li>
+	 *   <li>if the two media types have different {@linkplain #getType() types}, then they are considered equal and
+	 *   remain their current order.</li>
+	 *   <li>if either media type has a {@linkplain #isWildcardSubtype() wildcard subtype}, then the media type without
+	 *   the wildcard is sorted before the other.</li>
+	 *   <li>if the two media types have different {@linkplain #getSubtype() subtypes}, then they are considered equal
+	 *   and remain their current order.</li>
+	 *   <li>if the two media types have different {@linkplain #getQualityValue() quality value}, then the media type
+	 *   with the highest quality value is ordered before the other.</li>
+	 *   <li>if the two media types have a different amount of {@linkplain #getParameter(String) parameters}, then the
+	 *   media type with the most parameters is ordered before the other.</li>
+	 * </ol>
+	 *
+	 * <p>For example:
+	 * <blockquote>audio/basic &lt; audio/* &lt; *&#047;*</blockquote>
+	 * <blockquote>audio/* &lt; audio/*;q=0.7; audio/*;q=0.3</blockquote>
+	 * <blockquote>audio/basic;level=1 &lt; audio/basic</blockquote>
+	 * <blockquote>audio/basic == text/html</blockquote>
+	 * <blockquote>audio/basic == audio/wave</blockquote>
+	 *
+	 * @param mediaTypes the list of media types to be sorted
+	 * @see <a href="http://tools.ietf.org/html/rfc2616#section-14.1">HTTP 1.1, section 14.1</a>
+	 */
+	public static void sortBySpecificity(List<MediaType> mediaTypes) {
+		Assert.notNull(mediaTypes, "'mediaTypes' must not be null");
+		if (mediaTypes.size() > 1) {
+			Collections.sort(mediaTypes, SPECIFICITY_COMPARATOR);
+		}
+	}
+
+	static final Comparator<MediaType> SPECIFICITY_COMPARATOR = new Comparator<MediaType>() {
+
+		public int compare(MediaType mediaType1, MediaType mediaType2) {
+			if (mediaType1.isWildcardType() && !mediaType2.isWildcardType()) { // */* < audio/*
+				return 1;
+			}
+			else if (mediaType2.isWildcardType() && !mediaType1.isWildcardType()) { // audio/* > */*
+				return -1;
+			}
+			else if (!mediaType1.getType().equals(mediaType2.getType())) { // audio/basic == text/html
+				return 0;
+			}
+			else { // mediaType1.getType().equals(mediaType2.getType())
+				if (mediaType1.isWildcardSubtype() && !mediaType2.isWildcardSubtype()) { // audio/* < audio/basic
+					return 1;
+				}
+				else if (mediaType2.isWildcardSubtype() && !mediaType1.isWildcardSubtype()) { // audio/basic > audio/*
+					return -1;
+				}
+				else if (!mediaType1.getSubtype().equals(mediaType2.getSubtype())) { // audio/basic == audio/wave
+					return 0;
+				}
+				else { // mediaType2.getSubtype().equals(mediaType2.getSubtype())
+					double quality1 = mediaType1.getQualityValue();
+					double quality2 = mediaType2.getQualityValue();
+					int qualityComparison = Double.compare(quality2, quality1);
+					if (qualityComparison != 0) {
+						return qualityComparison;  // audio/*;q=0.7 < audio/*;q=0.3
+					} else {
+						int paramsSize1 = mediaType1.parameters.size();
+						int paramsSize2 = mediaType2.parameters.size();
+						return (paramsSize2 < paramsSize1 ? -1 : (paramsSize2 == paramsSize1 ? 0 : 1)); // audio/basic;level=1 < audio/basic
+					}
+				}
+			}
+		}
+	};
+
 }

org.springframework.web/src/main/java/org/springframework/web/client/RestTemplate.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2010 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.
@@ -412,7 +412,7 @@ public class RestTemplate extends HttpAccessor implements RestOperations {
 		public void doWithRequest(ClientHttpRequest request) throws IOException {
 			if (responseType != null) {
 				List<MediaType> allSupportedMediaTypes = new ArrayList<MediaType>();
-				for (HttpMessageConverter messageConverter : getMessageConverters()) {
+				for (HttpMessageConverter<?> messageConverter : getMessageConverters()) {
 					if (messageConverter.canRead(responseType, null)) {
 						List<MediaType> supportedMediaTypes = messageConverter.getSupportedMediaTypes();
 						for (MediaType supportedMediaType : supportedMediaTypes) {
@@ -425,7 +425,7 @@ public class RestTemplate extends HttpAccessor implements RestOperations {
 					}
 				}
 				if (!allSupportedMediaTypes.isEmpty()) {
-					Collections.sort(allSupportedMediaTypes);
+					MediaType.sortBySpecificity(allSupportedMediaTypes);
 					request.getHeaders().setAccept(allSupportedMediaTypes);
 				}
 			}
@@ -458,7 +458,7 @@ public class RestTemplate extends HttpAccessor implements RestOperations {
 		public void doWithRequest(ClientHttpRequest httpRequest) throws IOException {
 			super.doWithRequest(httpRequest);
 			if (requestBody != null) {
-				Class requestType = requestBody.getClass();
+				Class<?> requestType = requestBody.getClass();
 				for (HttpMessageConverter messageConverter : getMessageConverters()) {
 					if (messageConverter.canWrite(requestType, requestContentType)) {
 						messageConverter.write(requestBody, requestContentType, httpRequest);

org.springframework.web/src/test/java/org/springframework/http/MediaTypeTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2010 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.
@@ -20,6 +20,8 @@ import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Comparator;
+import java.util.Random;
 
 import static org.junit.Assert.*;
 import org.junit.Test;
@@ -49,11 +51,27 @@ public class MediaTypeTests {
 
 	@Test
 	public void testToString() throws Exception {
-		MediaType mediaType = new MediaType("text", "plain", Collections.singletonMap("q", "0.7"));
+		MediaType mediaType = new MediaType("text", "plain", 0.7);
 		String result = mediaType.toString();
 		assertEquals("Invalid toString() returned", "text/plain;q=0.7", result);
 	}
 
+	@Test(expected= IllegalArgumentException.class)
+	public void slashInType() {
+		new MediaType("text/plain");
+	}
+
+	@Test(expected= IllegalArgumentException.class)
+	public void slashInSubtype() {
+		new MediaType("text", "/");
+	}
+	
+	@Test
+	public void getDefaultQualityValue() {
+		MediaType mediaType = new MediaType("text", "plain");
+		assertEquals("Invalid quality value", 1, mediaType.getQualityValue(), 0D);
+	}
+
 	@Test
 	public void parseMediaType() throws Exception {
 		String s = "audio/*; q=0.2";
@@ -94,50 +112,104 @@ public class MediaTypeTests {
 	}
 
 	@Test
-	public void compareTo() throws Exception {
+	public void specificityComparator() throws Exception {
 		MediaType audioBasic = new MediaType("audio", "basic");
+		MediaType audioWave = new MediaType("audio", "wave");
 		MediaType audio = new MediaType("audio");
-		MediaType audio03 = new MediaType("audio", "*", Collections.singletonMap("q", "0.3"));
-		MediaType audio07 = new MediaType("audio", "*", Collections.singletonMap("q", "0.7"));
+		MediaType audio03 = new MediaType("audio", "*", 0.3);
+		MediaType audio07 = new MediaType("audio", "*", 0.7);
+		MediaType audioBasicLevel = new MediaType("audio", "basic", Collections.singletonMap("level", "1"));
+		MediaType textHtml = new MediaType("text", "html");
 		MediaType all = MediaType.ALL;
 
+		Comparator<MediaType> comp = MediaType.SPECIFICITY_COMPARATOR;
+
 		// equal
-		assertEquals("Invalid comparison result", 0, audioBasic.compareTo(audioBasic));
-		assertEquals("Invalid comparison result", 0, audio.compareTo(audio));
-		assertEquals("Invalid comparison result", 0, audio07.compareTo(audio07));
+		assertEquals("Invalid comparison result", 0, comp.compare(audioBasic,audioBasic));
+		assertEquals("Invalid comparison result", 0, comp.compare(audio, audio));
+		assertEquals("Invalid comparison result", 0, comp.compare(audio07, audio07));
+		assertEquals("Invalid comparison result", 0, comp.compare(audio03, audio03));
+		assertEquals("Invalid comparison result", 0, comp.compare(audioBasicLevel, audioBasicLevel));
 
 		// specific to unspecific
-		assertTrue("Invalid comparison result", audioBasic.compareTo(audio) < 0);
-		assertTrue("Invalid comparison result", audioBasic.compareTo(all) < 0);
-		assertTrue("Invalid comparison result", audio.compareTo(all) < 0);
+		assertTrue("Invalid comparison result", comp.compare(audioBasic, audio) < 0);
+		assertTrue("Invalid comparison result", comp.compare(audioBasic, all) < 0);
+		assertTrue("Invalid comparison result", comp.compare(audio, all) < 0);
 
 		// unspecific to specific
-		assertTrue("Invalid comparison result", audio.compareTo(audioBasic) > 0);
-		assertTrue("Invalid comparison result", all.compareTo(audioBasic) > 0);
-		assertTrue("Invalid comparison result", all.compareTo(audio) > 0);
+		assertTrue("Invalid comparison result", comp.compare(audio, audioBasic) > 0);
+		assertTrue("Invalid comparison result", comp.compare(all, audioBasic) > 0);
+		assertTrue("Invalid comparison result", comp.compare(all, audio) > 0);
 
 		// qualifiers
-		assertTrue("Invalid comparison result", audio.compareTo(audio07) < 0);
-		assertTrue("Invalid comparison result", audio07.compareTo(audio03) < 0);
-		assertTrue("Invalid comparison result", audio03.compareTo(all) > 0);
+		assertTrue("Invalid comparison result", comp.compare(audio, audio07) < 0);
+		assertTrue("Invalid comparison result", comp.compare(audio07, audio) > 0);
+		assertTrue("Invalid comparison result", comp.compare(audio07, audio03) < 0);
+		assertTrue("Invalid comparison result", comp.compare(audio03, audio07) > 0);
+		assertTrue("Invalid comparison result", comp.compare(audio03, all) < 0);
+		assertTrue("Invalid comparison result", comp.compare(all, audio03) > 0);
+
+		// other parameters
+		assertTrue("Invalid comparison result", comp.compare(audioBasic, audioBasicLevel) > 0);
+		assertTrue("Invalid comparison result", comp.compare(audioBasicLevel, audioBasic) < 0);
+
+		// different types
+		assertEquals("Invalid comparison result", 0, comp.compare(audioBasic, textHtml));
+		assertEquals("Invalid comparison result", 0, comp.compare(textHtml, audioBasic));
+
+		// different subtypes
+		assertEquals("Invalid comparison result", 0, comp.compare(audioBasic, audioWave));
+		assertEquals("Invalid comparison result", 0, comp.compare(audioWave, audioBasic));
+	}
+
+	@Test
+	public void sortBySpecificityRelated() {
+		MediaType audioBasic = new MediaType("audio", "basic");
+		MediaType audio = new MediaType("audio");
+		MediaType audio03 = new MediaType("audio", "*", 0.3);
+		MediaType audio07 = new MediaType("audio", "*", 0.7);
+		MediaType audioBasicLevel = new MediaType("audio", "basic", Collections.singletonMap("level", "1"));
+		MediaType all = MediaType.ALL;
 
-		// sort
 		List<MediaType> expected = new ArrayList<MediaType>();
+		expected.add(audioBasicLevel);
 		expected.add(audioBasic);
 		expected.add(audio);
-		expected.add(all);
 		expected.add(audio07);
 		expected.add(audio03);
+		expected.add(all);
 
 		List<MediaType> result = new ArrayList<MediaType>(expected);
+		Random rnd = new Random();
+		// shuffle & sort 10 times
 		for (int i = 0; i < 10; i++) {
-			Collections.shuffle(result);
-			Collections.sort(result);
+			Collections.shuffle(result, rnd);
+			MediaType.sortBySpecificity(result);
 
 			for (int j = 0; j < result.size(); j++) {
-				assertEquals("Invalid media type at " + j, expected.get(j), result.get(j));
+				assertSame("Invalid media type at " + j, expected.get(j), result.get(j));
 			}
 		}
 	}
 
+	@Test
+	public void sortBySpecificityUnrelated() {
+		MediaType audioBasic = new MediaType("audio", "basic");
+		MediaType audioWave = new MediaType("audio", "wave");
+		MediaType textHtml = new MediaType("text", "html");
+
+		List<MediaType> expected = new ArrayList<MediaType>();
+		expected.add(textHtml);
+		expected.add(audioBasic);
+		expected.add(audioWave);
+
+		List<MediaType> result = new ArrayList<MediaType>(expected);
+		MediaType.sortBySpecificity(result);
+
+		for (int i = 0; i < result.size(); i++) {
+			assertSame("Invalid media type at " + i, expected.get(i), result.get(i));
+		}
+
+	}
+
 }