SOLR-9986: Add javadoc to DatePointField class

This commit is contained in:
Tomas Fernandez Lobbe 2017-03-22 10:52:14 -07:00
parent 6786089b0b
commit 8a99675392
1 changed files with 62 additions and 0 deletions

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@ -36,8 +36,70 @@ import org.apache.lucene.util.mutable.MutableValueDate;
import org.apache.lucene.util.mutable.MutableValueLong;
import org.apache.solr.search.QParser;
import org.apache.solr.uninverting.UninvertingReader;
import org.apache.solr.update.processor.TimestampUpdateProcessorFactory;
import org.apache.solr.util.DateMathParser;
/**
* FieldType that can represent any Date/Time with millisecond precision.
* <p>
* Date Format for the XML, incoming and outgoing:
* </p>
* <blockquote>
* A date field shall be of the form 1995-12-31T23:59:59Z
* The trailing "Z" designates UTC time and is mandatory
* (See below for an explanation of UTC).
* Optional fractional seconds are allowed, as long as they do not end
* in a trailing 0 (but any precision beyond milliseconds will be ignored).
* All other parts are mandatory.
* </blockquote>
* <p>
* This format was derived to be standards compliant (ISO 8601) and is a more
* restricted form of the
* <a href="http://www.w3.org/TR/xmlschema-2/#dateTime-canonical-representation">canonical
* representation of dateTime</a> from XML schema part 2. Examples...
* </p>
* <ul>
* <li>1995-12-31T23:59:59Z</li>
* <li>1995-12-31T23:59:59.9Z</li>
* <li>1995-12-31T23:59:59.99Z</li>
* <li>1995-12-31T23:59:59.999Z</li>
* </ul>
* <p>
* Note that <code>DatePointField</code> is lenient with regards to parsing fractional
* seconds that end in trailing zeros and will ensure that those values
* are indexed in the correct canonical format.
* </p>
* <p>
* This FieldType also supports incoming "Date Math" strings for computing
* values by adding/rounding internals of time relative either an explicit
* datetime (in the format specified above) or the literal string "NOW",
* ie: "NOW+1YEAR", "NOW/DAY", "1995-12-31T23:59:59.999Z+5MINUTES", etc...
* -- see {@link DateMathParser} for more examples.
* </p>
* <p>
* <b>NOTE:</b> Although it is possible to configure a <code>DatePointField</code>
* instance with a default value of "<code>NOW</code>" to compute a timestamp
* of when the document was indexed, this is not advisable when using SolrCloud
* since each replica of the document may compute a slightly different value.
* {@link TimestampUpdateProcessorFactory} is recommended instead.
* </p>
*
* <p>
* Explanation of "UTC"...
* </p>
* <blockquote>
* "In 1970 the Coordinated Universal Time system was devised by an
* international advisory group of technical experts within the International
* Telecommunication Union (ITU). The ITU felt it was best to designate a
* single abbreviation for use in all languages in order to minimize
* confusion. Since unanimous agreement could not be achieved on using
* either the English word order, CUT, or the French word order, TUC, the
* acronym UTC was chosen as a compromise."
* </blockquote>
*
* @see TrieDateField
* @see PointField
*/
public class DatePointField extends PointField implements DateValueFieldType {
public DatePointField() {