Update LocaleContextResolver to implement LocaleResolver

This commit updates LocaleContextResolver to implement LocaleResolver
using default methods, which simplifies AbstractLocaleContextResolver
and aligns it more closely with AbstractLocaleResolver.

See gh-27609

spring-webmvc/src/main/java/org/springframework/web/servlet/LocaleContextResolver.java

@@ -22,12 +22,16 @@ import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 
 import org.springframework.context.i18n.LocaleContext;
+import org.springframework.context.i18n.SimpleLocaleContext;
 import org.springframework.lang.Nullable;
 
 /**
  * Extension of {@link LocaleResolver} that adds support for a rich locale context
  * (potentially including locale and time zone information).
  *
+ * <p>Also provides pre-implemented versions of {@link #resolveLocale} and {@link #setLocale},
+ * delegating to {@link #resolveLocaleContext} and {@link #setLocaleContext}.
+ *
  * @author Juergen Hoeller
  * @since 4.0
  * @see org.springframework.context.i18n.LocaleContext
@@ -73,4 +77,15 @@ public interface LocaleContextResolver extends LocaleResolver {
 	void setLocaleContext(HttpServletRequest request, @Nullable HttpServletResponse response,
 			@Nullable LocaleContext localeContext);
 
+	@Override
+	default Locale resolveLocale(HttpServletRequest request) {
+		Locale locale = resolveLocaleContext(request).getLocale();
+		return (locale != null ? locale : request.getLocale());
+	}
+
+	@Override
+	default void setLocale(HttpServletRequest request, @Nullable HttpServletResponse response, @Nullable Locale locale) {
+		setLocaleContext(request, response, (locale != null ? new SimpleLocaleContext(locale) : null));
+	}
+
 }

spring-webmvc/src/main/java/org/springframework/web/servlet/i18n/AbstractLocaleContextResolver.java

@@ -16,13 +16,8 @@
 
 package org.springframework.web.servlet.i18n;
 
-import java.util.Locale;
 import java.util.TimeZone;
 
-import jakarta.servlet.http.HttpServletRequest;
-import jakarta.servlet.http.HttpServletResponse;
-
-import org.springframework.context.i18n.SimpleLocaleContext;
 import org.springframework.lang.Nullable;
 import org.springframework.web.servlet.LocaleContextResolver;
 
@@ -32,9 +27,6 @@ import org.springframework.web.servlet.LocaleContextResolver;
  * <p>Provides support for a {@linkplain #setDefaultLocale(Locale) default locale}
  * and a {@linkplain #setDefaultTimeZone(TimeZone) default time zone}.
  *
- * <p>Also provides pre-implemented versions of {@link #resolveLocale} and {@link #setLocale},
- * delegating to {@link #resolveLocaleContext} and {@link #setLocaleContext}.
- *
  * @author Juergen Hoeller
  * @since 4.0
  * @see #setDefaultLocale
@@ -63,16 +55,4 @@ public abstract class AbstractLocaleContextResolver extends AbstractLocaleResolv
 		return this.defaultTimeZone;
 	}
 
-
-	@Override
-	public Locale resolveLocale(HttpServletRequest request) {
-		Locale locale = resolveLocaleContext(request).getLocale();
-		return (locale != null ? locale : request.getLocale());
-	}
-
-	@Override
-	public void setLocale(HttpServletRequest request, @Nullable HttpServletResponse response, @Nullable Locale locale) {
-		setLocaleContext(request, response, (locale != null ? new SimpleLocaleContext(locale) : null));
-	}
-
 }