Turn off use of path extensions by default

Closes gh-23915

spring-web/src/main/java/org/springframework/web/accept/ContentNegotiationManagerFactoryBean.java

@@ -50,18 +50,18 @@ import org.springframework.web.context.ServletContextAware;
  * <th>Enabled Or Not</th>
  * </tr>
  * <tr>
- * <td>{@link #setFavorPathExtension favorPathExtension}</td>
- * <td>true</td>
- * <td>{@link PathExtensionContentNegotiationStrategy}</td>
- * <td>Enabled</td>
- * </tr>
- * <tr>
  * <td>{@link #setFavorParameter favorParameter}</td>
  * <td>false</td>
  * <td>{@link ParameterContentNegotiationStrategy}</td>
  * <td>Off</td>
  * </tr>
  * <tr>
+ * <td>{@link #setFavorPathExtension favorPathExtension}</td>
+ * <td>false (as of 5.3)</td>
+ * <td>{@link PathExtensionContentNegotiationStrategy}</td>
+ * <td>Off</td>
+ * </tr>
+ * <tr>
  * <td>{@link #setIgnoreAcceptHeader ignoreAcceptHeader}</td>
  * <td>false</td>
  * <td>{@link HeaderContentNegotiationStrategy}</td>
@@ -104,11 +104,11 @@ public class ContentNegotiationManagerFactoryBean
 	private List<ContentNegotiationStrategy> strategies;
 
 
-	private boolean favorPathExtension = true;
-
 	private boolean favorParameter = false;
 
-	private boolean ignoreAcceptHeader = false;
+	private String parameterName = "format";
+
+	private boolean favorPathExtension = true;
 
 	private Map<String, MediaType> mediaTypes = new HashMap<>();
 
@@ -117,7 +117,7 @@ public class ContentNegotiationManagerFactoryBean
 	@Nullable
 	private Boolean useRegisteredExtensionsOnly;
 
-	private String parameterName = "format";
+	private boolean ignoreAcceptHeader = false;
 
 	@Nullable
 	private ContentNegotiationStrategy defaultNegotiationStrategy;
@@ -141,17 +141,35 @@ public class ContentNegotiationManagerFactoryBean
 		this.strategies = (strategies != null ? new ArrayList<>(strategies) : null);
 	}
 
+	/**
+	 * Whether a request parameter ("format" by default) should be used to
+	 * determine the requested media type. For this option to work you must
+	 * register {@link #setMediaTypes media type mappings}.
+	 * <p>By default this is set to {@code false}.
+	 * @see #setParameterName
+	 */
+	public void setFavorParameter(boolean favorParameter) {
+		this.favorParameter = favorParameter;
+	}
+
+	/**
+	 * Set the query parameter name to use when {@link #setFavorParameter} is on.
+	 * <p>The default parameter name is {@code "format"}.
+	 */
+	public void setParameterName(String parameterName) {
+		Assert.notNull(parameterName, "parameterName is required");
+		this.parameterName = parameterName;
+	}
+
 	/**
 	 * Whether the path extension in the URL path should be used to determine
 	 * the requested media type.
-	 * <p>By default this is set to {@code true} in which case a request
-	 * for {@code /hotels.pdf} will be interpreted as a request for
-	 * {@code "application/pdf"} regardless of the 'Accept' header.
+	 * <p>By default this is set to {@code false} in which case path extensions
+	 * have no impact on content negotiation.
 	 * @deprecated as of 5.2.4. See class-level note on the deprecation of path
 	 * extension config options. As there is no replacement for this method,
-	 * for the time being it's necessary to continue using it in order to set it
-	 * to {@code false}. In 5.3 when {@code false} becomes the default, use of
-	 * this property will no longer be necessary.
+	 * in 5.2.x it is necessary to set it to {@code false}. In 5.3 {@code false}
+	 * becomes the default, and use of this property is longer be necessary.
 	 */
 	@Deprecated
 	public void setFavorPathExtension(boolean favorPathExtension) {
@@ -224,8 +242,8 @@ public class ContentNegotiationManagerFactoryBean
 	/**
 	 * Indicate whether to use the Java Activation Framework as a fallback option
 	 * to map from file extensions to media types.
-	 * @deprecated as of 5.0, in favor of {@link #setUseRegisteredExtensionsOnly(boolean)}, which
-	 * has reverse behavior.
+	 * @deprecated as of 5.0, in favor of {@link #setUseRegisteredExtensionsOnly(boolean)},
+	 * which has reverse behavior.
 	 */
 	@Deprecated
 	public void setUseJaf(boolean useJaf) {
@@ -247,26 +265,6 @@ public class ContentNegotiationManagerFactoryBean
 		return (this.useRegisteredExtensionsOnly != null && this.useRegisteredExtensionsOnly);
 	}
 
-	/**
-	 * Whether a request parameter ("format" by default) should be used to
-	 * determine the requested media type. For this option to work you must
-	 * register {@link #setMediaTypes media type mappings}.
-	 * <p>By default this is set to {@code false}.
-	 * @see #setParameterName
-	 */
-	public void setFavorParameter(boolean favorParameter) {
-		this.favorParameter = favorParameter;
-	}
-
-	/**
-	 * Set the query parameter name to use when {@link #setFavorParameter} is on.
-	 * <p>The default parameter name is {@code "format"}.
-	 */
-	public void setParameterName(String parameterName) {
-		Assert.notNull(parameterName, "parameterName is required");
-		this.parameterName = parameterName;
-	}
-
 	/**
 	 * Whether to disable checking the 'Accept' request header.
 	 * <p>By default this value is set to {@code false}.