Missing @Nullable annotations in WebFlux, in particular around locale resolution

Issue: SPR-15036
Issue: SPR-15540

spring-web/src/main/java/org/springframework/http/server/reactive/DefaultPathSegmentContainer.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.http.server.reactive;
 
 import java.nio.charset.Charset;
@@ -21,6 +22,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.stream.Collectors;
 
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
 import org.springframework.util.LinkedMultiValueMap;
@@ -93,7 +95,7 @@ class DefaultPathSegmentContainer implements PathSegmentContainer {
 
 
 	@Override
-	public boolean equals(Object other) {
+	public boolean equals(@Nullable Object other) {
 		if (this == other) {
 			return true;
 		}
@@ -224,12 +226,10 @@ class DefaultPathSegmentContainer implements PathSegmentContainer {
 
 		private final MultiValueMap<String, String> parameters;
 
-
 		DefaultPathSegment(String value, String valueDecoded, String semicolonContent,
 				MultiValueMap<String, String> params) {
 
 			Assert.isTrue(!value.contains("/"), "Invalid path segment value: " + value);
-
 			this.value = value;
 			this.valueDecoded = valueDecoded;
 			this.valueCharsDecoded = valueDecoded.toCharArray();
@@ -238,7 +238,6 @@ class DefaultPathSegmentContainer implements PathSegmentContainer {
 			this.parameters = CollectionUtils.unmodifiableMultiValueMap(params);
 		}
 
-
 		@Override
 		public String value() {
 			return this.value;
@@ -269,9 +268,8 @@ class DefaultPathSegmentContainer implements PathSegmentContainer {
 			return this.parameters;
 		}
 
-
 		@Override
-		public boolean equals(Object other) {
+		public boolean equals(@Nullable Object other) {
 			if (this == other) {
 				return true;
 			}

spring-web/src/main/java/org/springframework/http/server/reactive/DefaultRequestPath.java

@@ -19,6 +19,7 @@ import java.net.URI;
 import java.nio.charset.Charset;
 import java.util.List;
 
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
@@ -126,7 +127,7 @@ class DefaultRequestPath implements RequestPath {
 
 
 	@Override
-	public boolean equals(Object other) {
+	public boolean equals(@Nullable Object other) {
 		if (this == other) {
 			return true;
 		}

spring-web/src/main/java/org/springframework/web/server/i18n/AcceptHeaderLocaleContextResolver.java

@@ -50,7 +50,7 @@ public class AcceptHeaderLocaleContextResolver implements LocaleContextResolver
 	 * determined via {@link HttpHeaders#getAcceptLanguageAsLocales()}.
 	 * @param locales the supported locales
 	 */
-	public void setSupportedLocales(List<Locale> locales) {
+	public void setSupportedLocales(@Nullable List<Locale> locales) {
 		this.supportedLocales.clear();
 		if (locales != null) {
 			this.supportedLocales.addAll(locales);

spring-web/src/main/java/org/springframework/web/server/i18n/LocaleContextResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -36,7 +36,6 @@ public interface LocaleContextResolver {
 
 	/**
 	 * Resolve the current locale context via the given exchange.
-	 *
 	 * <p>The returned context may be a
 	 * {@link org.springframework.context.i18n.TimeZoneAwareLocaleContext},
 	 * containing a locale with associated time zone information.
@@ -44,7 +43,7 @@ public interface LocaleContextResolver {
 	 * <p>Custom resolver implementations may also return extra settings in
 	 * the returned context, which again can be accessed through downcasting.
 	 * @param exchange current server exchange
-	 * @return the current locale context (never {@code null}
+	 * @return the current locale context (never {@code null})
 	 */
 	LocaleContext resolveLocaleContext(ServerWebExchange exchange);
 

spring-web/src/main/java/org/springframework/web/util/pattern/PathPatternComparator.java

@@ -18,6 +18,8 @@ package org.springframework.web.util.pattern;
 
 import java.util.Comparator;
 
+import org.springframework.lang.Nullable;
+
 /**
  * {@link PathPattern} comparator that takes account of a specified
  * path and sorts anything that exactly matches it to be first.
@@ -34,12 +36,14 @@ public class PathPatternComparator implements Comparator<PathPattern> {
 
 	private final String path;
 
+
 	public PathPatternComparator(String path) {
 		this.path = path;
 	}
 
+
 	@Override
-	public int compare(PathPattern o1, PathPattern o2) {
+	public int compare(@Nullable PathPattern o1, @Nullable PathPattern o2) {
 		// Nulls get sorted to the end
 		if (o1 == null) {
 			return (o2 == null ? 0 : +1);
@@ -47,6 +51,7 @@ public class PathPatternComparator implements Comparator<PathPattern> {
 		else if (o2 == null) {
 			return -1;
 		}
+
 		// exact matches get sorted first
 		if (o1.getPatternString().equals(path)) {
 			return (o2.getPatternString().equals(path)) ? 0 : -1;
@@ -54,6 +59,7 @@ public class PathPatternComparator implements Comparator<PathPattern> {
 		else if (o2.getPatternString().equals(path)) {
 			return +1;
 		}
+
 		// compare pattern specificity
 		int result = o1.compareTo(o2);
 		// if equal specificity, sort using pattern string
@@ -63,4 +69,4 @@ public class PathPatternComparator implements Comparator<PathPattern> {
 		return result;
 	}
 
-}
+}