WebFlux support for LocaleContext related arguments

Issue: SPR-15998

spring-webflux/src/main/java/org/springframework/web/reactive/result/method/annotation/ServerWebExchangeArgumentResolver.java

@@ -16,12 +16,19 @@
 
 package org.springframework.web.reactive.result.method.annotation;
 
+import java.time.ZoneId;
+import java.util.Locale;
+import java.util.TimeZone;
+
+import org.springframework.context.i18n.LocaleContext;
+import org.springframework.context.i18n.TimeZoneAwareLocaleContext;
 import org.springframework.core.MethodParameter;
 import org.springframework.core.ReactiveAdapterRegistry;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpRequest;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.http.server.reactive.ServerHttpResponse;
+import org.springframework.lang.Nullable;
 import org.springframework.web.reactive.BindingContext;
 import org.springframework.web.reactive.result.method.HandlerMethodArgumentResolverSupport;
 import org.springframework.web.reactive.result.method.SyncHandlerMethodArgumentResolver;
@@ -36,6 +43,9 @@ import org.springframework.web.util.UriComponentsBuilder;
  * <li>{@link ServerHttpRequest}
  * <li>{@link ServerHttpResponse}
  * <li>{@link HttpMethod}
+ * <li>{@link Locale}
+ * <li>{@link TimeZone}
+ * <li>{@link ZoneId}
  * <li>{@link UriBuilder} or {@link UriComponentsBuilder} -- for building URL's
  * relative to the current request
  * </ul>
@@ -63,6 +73,9 @@ public class ServerWebExchangeArgumentResolver extends HandlerMethodArgumentReso
 						ServerHttpRequest.class.isAssignableFrom(type) ||
 						ServerHttpResponse.class.isAssignableFrom(type) ||
 						HttpMethod.class == type ||
+						Locale.class == type ||
+						TimeZone.class == type ||
+						ZoneId.class == type ||
 						UriBuilder.class == type || UriComponentsBuilder.class == type);
 	}
 
@@ -83,6 +96,19 @@ public class ServerWebExchangeArgumentResolver extends HandlerMethodArgumentReso
 		else if (HttpMethod.class == paramType) {
 			return exchange.getRequest().getMethod();
 		}
+		else if (Locale.class == paramType) {
+			return exchange.getLocaleContext().getLocale();
+		}
+		else if (TimeZone.class == paramType) {
+			LocaleContext localeContext = exchange.getLocaleContext();
+			TimeZone timeZone = getTimeZone(localeContext);
+			return timeZone != null ? timeZone : TimeZone.getDefault();
+		}
+		else if (ZoneId.class == paramType) {
+			LocaleContext localeContext = exchange.getLocaleContext();
+			TimeZone timeZone = getTimeZone(localeContext);
+			return timeZone != null ? timeZone.toZoneId() : ZoneId.systemDefault();
+		}
 		else if (UriBuilder.class == paramType || UriComponentsBuilder.class == paramType) {
 			return UriComponentsBuilder.fromHttpRequest(exchange.getRequest());
 		}
@@ -93,4 +119,13 @@ public class ServerWebExchangeArgumentResolver extends HandlerMethodArgumentReso
 		}
 	}
 
+	@Nullable
+	private TimeZone getTimeZone(LocaleContext localeContext) {
+		TimeZone timeZone = null;
+		if (localeContext instanceof TimeZoneAwareLocaleContext) {
+			timeZone = ((TimeZoneAwareLocaleContext) localeContext).getTimeZone();
+		}
+		return timeZone;
+	}
+
 }

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/ServerWebExchangeArgumentResolverTests.java

@@ -16,6 +16,10 @@
 
 package org.springframework.web.reactive.result.method.annotation;
 
+import java.time.ZoneId;
+import java.util.Locale;
+import java.util.TimeZone;
+
 import org.junit.Test;
 import reactor.core.publisher.Mono;
 
@@ -60,6 +64,9 @@ public class ServerWebExchangeArgumentResolverTests {
 		assertTrue(this.resolver.supportsParameter(this.testMethod.arg(ServerHttpRequest.class)));
 		assertTrue(this.resolver.supportsParameter(this.testMethod.arg(ServerHttpResponse.class)));
 		assertTrue(this.resolver.supportsParameter(this.testMethod.arg(HttpMethod.class)));
+		assertTrue(this.resolver.supportsParameter(this.testMethod.arg(Locale.class)));
+		assertTrue(this.resolver.supportsParameter(this.testMethod.arg(TimeZone.class)));
+		assertTrue(this.resolver.supportsParameter(this.testMethod.arg(ZoneId.class)));
 		assertTrue(this.resolver.supportsParameter(this.testMethod.arg(UriComponentsBuilder.class)));
 		assertTrue(this.resolver.supportsParameter(this.testMethod.arg(UriBuilder.class)));
 
@@ -81,6 +88,13 @@ public class ServerWebExchangeArgumentResolverTests {
 		testResolveArgument(this.testMethod.arg(ServerHttpRequest.class), this.exchange.getRequest());
 		testResolveArgument(this.testMethod.arg(ServerHttpResponse.class), this.exchange.getResponse());
 		testResolveArgument(this.testMethod.arg(HttpMethod.class), HttpMethod.GET);
+		testResolveArgument(this.testMethod.arg(TimeZone.class), TimeZone.getDefault());
+		testResolveArgument(this.testMethod.arg(ZoneId.class), ZoneId.systemDefault());
+	}
+
+	private void testResolveArgument(MethodParameter parameter, Object expected) {
+		Mono<Object> mono = this.resolver.resolveArgument(parameter, new BindingContext(), this.exchange);
+		assertEquals(expected, mono.block());
 	}
 
 	@Test
@@ -93,10 +107,6 @@ public class ServerWebExchangeArgumentResolverTests {
 		assertEquals("/path/next", ((UriComponentsBuilder) value).path("/next").build().toUriString());
 	}
 
-	private void testResolveArgument(MethodParameter parameter, Object expected) {
-		Mono<Object> mono = this.resolver.resolveArgument(parameter, new BindingContext(), this.exchange);
-		assertSame(expected, mono.block());
-	}
 
 
 	@SuppressWarnings("unused")
@@ -106,6 +116,9 @@ public class ServerWebExchangeArgumentResolverTests {
 			ServerHttpResponse response,
 			WebSession session,
 			HttpMethod httpMethod,
+			Locale locale,
+			TimeZone timeZone,
+			ZoneId zoneId,
 			UriComponentsBuilder uriComponentsBuilder,
 			UriBuilder uriBuilder,
 			String s,

src/docs/asciidoc/web/webflux.adoc

@@ -873,15 +873,13 @@ Supports reactive types.
 |`org.springframework.http.HttpMethod`
 |The HTTP method of the request.
 
-// TODO: not supported
+ |`java.util.Locale`
-// |`java.util.Locale`
+ |The current request locale, determined by the most specific `LocaleResolver` available, in
-// |The current request locale, determined by the most specific `LocaleResolver` available, in
+ effect, the configured `LocaleResolver`/`LocaleContextResolver`.
-// effect, the configured `LocaleResolver`/`LocaleContextResolver`.
+
-
+|Java 6+: `java.util.TimeZone` +
-// TODO: not supported
+Java 8+: `java.time.ZoneId`
-//|Java 6+: `java.util.TimeZone` +
+|The time zone associated with the current request, as determined by a `LocaleContextResolver`.
-//Java 8+: `java.time.ZoneId`
-//|The time zone associated with the current request, as determined by a `LocaleContextResolver`.
 
 |`@PathVariable`
 |For access to URI template variables.