Use spring.mvc.date-pattern to also configure formatting of java.time.LocalDate.

Initial attempt and basis for discussions on how to fix spring-projectsgh-5523.

Author: britter

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration.java

@@ -16,11 +16,15 @@
 
 package org.springframework.boot.autoconfigure.web.servlet;
 
+import java.text.ParseException;
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Date;
 import java.util.List;
 import java.util.ListIterator;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Map.Entry;
 
@@ -255,6 +259,26 @@ public Formatter<Date> dateFormatter() {
 			return new DateFormatter(this.mvcProperties.getDateFormat());
 		}
 
+		@Bean
+		@ConditionalOnProperty(prefix = "spring.mvc", name = "date-format")
+		public Formatter<LocalDate> localDateFormatter() {
+			return new Formatter<LocalDate>() {
+
+				@Override
+				public LocalDate parse(String text, Locale locale) throws ParseException {
+					return LocalDate.parse(text,
+							DateTimeFormatter.ofPattern(
+									WebMvcAutoConfigurationAdapter.this.mvcProperties.getDateFormat(), locale));
+				}
+
+				@Override
+				public String print(LocalDate object, Locale locale) {
+					return DateTimeFormatter.ofPattern(
+							WebMvcAutoConfigurationAdapter.this.mvcProperties.getDateFormat(), locale).format(object);
+				}
+			};
+		}
+
 		@Override
 		public MessageCodesResolver getMessageCodesResolver() {
 			if (this.mvcProperties.getMessageCodesResolverFormat() != null) {

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfigurationTests.java

@@ -16,6 +16,7 @@
 
 package org.springframework.boot.autoconfigure.web.servlet;
 
+import java.time.LocalDate;
 import java.util.Date;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -367,8 +368,13 @@ public void overrideDateFormat() {
 				.run((context) -> {
 					FormattingConversionService conversionService = context
 							.getBean(FormattingConversionService.class);
+
 					Date date = new DateTime(1988, 6, 25, 20, 30).toDate();
-					assertThat(conversionService.convert(date, String.class))
+					assertThat(conversionService.convert(date, String.class)).as("java.util.Date")
+							.isEqualTo("25*06*1988");
+
+					LocalDate localDate = LocalDate.of(1988, 6, 25);
+					assertThat(conversionService.convert(localDate, String.class)).as("java.time.LocalDate")
 							.isEqualTo("25*06*1988");
 				});
 	}