Use own implementation of date formatters.

Original PR #1650 
Closes #1647

Author: sothawo

Diff for: src/main/java/org/springframework/data/elasticsearch/annotations/DateFormat.java

@@ -16,58 +16,73 @@
 package org.springframework.data.elasticsearch.annotations;
 
 /**
- * Values based on reference doc - https://www.elastic.co/guide/reference/mapping/date-format/
- * 
+ * Values based on reference doc - https://www.elastic.co/guide/reference/mapping/date-format/. The patterns are taken
+ * from this documentation and slightly adapted so that a Java {@link java.time.format.DateTimeFormatter} produces the
+ * same values as the Elasticsearch formatter.
+ *
  * @author Jakub Vavrik
  * @author Tim te Beek
  * @author Peter-Josef Meisch
  */
 public enum DateFormat {
-	none, //
-	custom, //
-	basic_date, //
-	basic_date_time, //
-	basic_date_time_no_millis, //
-	basic_ordinal_date, //
-	basic_ordinal_date_time, //
-	basic_ordinal_date_time_no_millis, //
-	basic_time, //
-	basic_time_no_millis, //
-	basic_t_time, //
-	basic_t_time_no_millis, //
-	basic_week_date, //
-	basic_week_date_time, //
-	basic_week_date_time_no_millis, //
-	date, //
-	date_hour, //
-	date_hour_minute, //
-	date_hour_minute_second, //
-	date_hour_minute_second_fraction, //
-	date_hour_minute_second_millis, //
-	date_optional_time, //
-	date_time, //
-	date_time_no_millis, //
-	epoch_millis, //
-	epoch_second, //
-	hour, //
-	hour_minute, //
-	hour_minute_second, //
-	hour_minute_second_fraction, //
-	hour_minute_second_millis, //
-	ordinal_date, //
-	ordinal_date_time, //
-	ordinal_date_time_no_millis, //
-	time, //
-	time_no_millis, //
-	t_time, //
-	t_time_no_millis, //
-	week_date, //
-	week_date_time, //
-	week_date_time_no_millis, //
-	weekyear, //
-	weekyear_week, //
-	weekyear_week_day, //
-	year, //
-	year_month, //
-	year_month_day //
+	none(""), //
+	custom(""), //
+	basic_date("uuuuMMdd"), //
+	basic_date_time("uuuuMMdd'T'HHmmss.SSSXXX"), //
+	basic_date_time_no_millis("uuuuMMdd'T'HHmmssXXX"), //
+	basic_ordinal_date("uuuuDDD"), //
+	basic_ordinal_date_time("yyyyDDD'T'HHmmss.SSSXXX"), //
+	basic_ordinal_date_time_no_millis("yyyyDDD'T'HHmmssXXX"), //
+	basic_time("HHmmss.SSSXXX"), //
+	basic_time_no_millis("HHmmssXXX"), //
+	basic_t_time("'T'HHmmss.SSSXXX"), //
+	basic_t_time_no_millis("'T'HHmmssXXX"), //
+	basic_week_date("YYYY'W'wwe"), // week-based-year!
+	basic_week_date_time("YYYY'W'wwe'T'HHmmss.SSSX"), // here Elasticsearch uses a different zone format
+	basic_week_date_time_no_millis("YYYY'W'wwe'T'HHmmssX"), //
+	date("uuuu-MM-dd"), //
+	date_hour("uuuu-MM-dd'T'HH"), //
+	date_hour_minute("uuuu-MM-dd'T'HH:mm"), //
+	date_hour_minute_second("uuuu-MM-dd'T'HH:mm:ss"), //
+	date_hour_minute_second_fraction("uuuu-MM-dd'T'HH:mm:ss.SSS"), //
+	date_hour_minute_second_millis("uuuu-MM-dd'T'HH:mm:ss.SSS"), //
+	date_optional_time("uuuu-MM-dd['T'HH:mm:ss.SSSXXX]"), //
+	date_time("uuuu-MM-dd'T'HH:mm:ss.SSSXXX"), //
+	date_time_no_millis("uuuu-MM-dd'T'HH:mm:ssVV"), // here Elasticsearch uses the zone-id in it's implementation
+	epoch_millis("epoch_millis"), //
+	epoch_second("epoch_second"), //
+	hour("HH"), //
+	hour_minute("HH:mm"), //
+	hour_minute_second("HH:mm:ss"), //
+	hour_minute_second_fraction("HH:mm:ss.SSS"), //
+	hour_minute_second_millis("HH:mm:ss.SSS"), //
+	ordinal_date("uuuu-DDD"), //
+	ordinal_date_time("uuuu-DDD'T'HH:mm:ss.SSSXXX"), //
+	ordinal_date_time_no_millis("uuuu-DDD'T'HH:mm:ssXXX"), //
+	time("HH:mm:ss.SSSXXX"), //
+	time_no_millis("HH:mm:ssXXX"), //
+	t_time("'T'HH:mm:ss.SSSXXX"), //
+	t_time_no_millis("'T'HH:mm:ssXXX"), //
+	week_date("YYYY-'W'ww-e"), //
+	week_date_time("YYYY-'W'ww-e'T'HH:mm:ss.SSSXXX"), //
+	week_date_time_no_millis("YYYY-'W'ww-e'T'HH:mm:ssXXX"), //
+	weekyear(""), // no TemporalAccessor available for these 3
+	weekyear_week(""), //
+	weekyear_week_day(""), //
+	year("uuuu"), //
+	year_month("uuuu-MM"), //
+	year_month_day("uuuu-MM-dd"); //
+
+	private final String pattern;
+
+	DateFormat(String pattern) {
+		this.pattern = pattern;
+	}
+
+	/**
+	 * @since 4.2
+	 */
+	public String getPattern() {
+		return pattern;
+	}
 }

Diff for: src/main/java/org/springframework/data/elasticsearch/core/convert/DateFormatter.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2021 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.elasticsearch.core.convert;
+
+import java.time.temporal.TemporalAccessor;
+
+/**
+ * Interface to convert from and to {@link TemporalAccessor}s.
+ * 
+ * @author Peter-Josef Meisch
+ * @since 4.2
+ */
+public interface DateFormatter {
+	/**
+	 * Formats a {@link TemporalAccessor} into a String.
+	 * 
+	 * @param accessor must not be {@literal null}
+	 * @return the formatted String
+	 */
+	String format(TemporalAccessor accessor);
+
+	/**
+	 * Parses a String into a {@link TemporalAccessor}.
+	 * 
+	 * @param input the String to parse, must not be {@literal null}
+	 * @param type the class of T
+	 * @param <T> the {@link TemporalAccessor} implementation
+	 * @return the parsed instance
+	 */
+	<T extends TemporalAccessor> T parse(String input, Class<T> type);
+}