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/* * Copyright (C) 2012-2015 DataStax Inc. * * 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 * * http://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 com.datastax.driver.extras.codecs.joda; import com.datastax.driver.core.*; import com.datastax.driver.core.exceptions.InvalidTypeException; import org.joda.time.DateTime; import org.joda.time.DateTimeZone; import org.joda.time.format.DateTimeFormatter; import org.joda.time.format.ISODateTimeFormat; import java.nio.ByteBuffer; import java.util.List; import static com.datastax.driver.core.ParseUtils.isLongLiteral; import static com.datastax.driver.core.ParseUtils.quote; import static com.google.common.base.Preconditions.checkArgument; /** * {@link TypeCodec} that maps * {@link DateTime} to CQL {@code tuple<timestamp,varchar>}, * providing a pattern for maintaining timezone information in * Cassandra. * <p/> * Since Cassandra's <code>timestamp</code> type preserves only * milliseconds since epoch, any timezone information * would normally be lost. By using a * <code>tuple<timestamp,varchar></code> a timezone ID can be * persisted in the <code>varchar</code> field such that when the * value is deserialized the timezone is * preserved. * <p/> * <strong>IMPORTANT</strong>: this codec's {@link #format(Object) format} method formats * timestamps as CQL literal strings using an ISO-8601 format that includes milliseconds. * <strong>This format is incompatible with Cassandra versions < 2.0.9.</strong> * * @see <a href="https://cassandra.apache.org/doc/cql3/CQL-2.2.html#usingtimestamps">'Working with timestamps' section of CQL specification</a> */ public class DateTimeCodec extends TypeCodec.AbstractTupleCodec<DateTime> { /** * A {@link DateTimeFormatter} that parses (most) of * the ISO-8601 formats accepted in CQL. */ private static final DateTimeFormatter DEFAULT_PARSER = ISODateTimeFormat.dateOptionalTimeParser(); /** * A {@link DateTimeFormatter} that prints timestamps * with a full ISO-8601 date and time format, including the time zone (Z). */ private static final DateTimeFormatter DEFFAULT_PRINTER = ISODateTimeFormat.dateTime().withZoneUTC(); private final DateTimeFormatter parser; private final DateTimeFormatter printer; /** * Creates a new {@link DateTimeCodec} for the given tuple, * using a default parser and a default printer to handle * the timestamp component of the tuple. * <p> * The default formatter and printer produce and parse CQL timestamp literals of the following form: * <ol> * <li>The printer will always produce a full ISO-8601 date and time pattern, including year, * month, day, hour, minutes, seconds and milliseconds, * followed by the zone ID {@code Z} (UTC), e.g. {@code 2010-06-30T01:20:47.999Z}; * note that timestamp components are always printed in UTC time, hence the zone ID {@code Z}.</li> * <li>The parser accepts most ISO-8601 date and time patterns, the time part (minutes, seconds, milliseconds) being optional.</li> * </ol> * <p> * Note that it is not possible to customize the parsing and printing of * the zone component of the tuple. This codec prints either a zone offset such as {@code -07:00}, * or a zone ID such as {@code UTC} or {@code Europe/Paris}, * depending on what is the best information is available. * * @param tupleType The tuple type this codec should handle. * It must be a {@code tuple<timestamp,varchar>}. * @throws IllegalArgumentException if the provided tuple type is not a {@code tuple<timestamp,varchar>}. */ public DateTimeCodec(TupleType tupleType) { this(tupleType, DEFAULT_PARSER, DEFFAULT_PRINTER); } /** * Creates a new {@link DateTimeCodec} for the given tuple, * using the provided {@link DateTimeFormatter parser} and {@link DateTimeFormatter printer} * to format and print the timestamp component of the tuple. * <p> * Use this constructor if you intend to customize the way the codec * parses and formats timestamps. Beware that Cassandra only accepts * timestamp literals in some of the most common ISO-8601 formats; * attempting to use non-standard formats could result in invalid CQL literals. * <p> * Note that it is not possible to customize the parsing and printing of * the zone component of the tuple. This codec prints either a zone offset such as {@code -07:00}, * or a zone ID such as {@code UTC} or {@code Europe/Paris}, * depending on what information is available. * * @param tupleType The tuple type this codec should handle. * It must be a {@code tuple<timestamp,varchar>}. * @param parser The {@link DateTimeFormatter parser} to use * to parse the timestamp component of the tuple. * It should be lenient enough to accept most of the ISO-8601 formats * accepted by Cassandra as valid CQL literals. * @param printer The {@link DateTimeFormatter printer} to use * to format the timestamp component of the tuple. * This printer should be configured to always format timestamps in UTC * (see {@link DateTimeFormatter#withZoneUTC()}. * @throws IllegalArgumentException if the provided tuple type is not a {@code tuple<timestamp,varchar>}. */ public DateTimeCodec(TupleType tupleType, DateTimeFormatter parser, DateTimeFormatter printer) { super(tupleType, DateTime.class); this.parser = parser; this.printer = printer; List<DataType> types = tupleType.getComponentTypes(); checkArgument( types.size() == 2 && types.get(0).equals(DataType.timestamp()) && types.get(1).equals(DataType.varchar()), "Expected tuple<timestamp,varchar>, got %s", tupleType); } @Override protected DateTime newInstance() { return null; } @Override protected ByteBuffer serializeField(DateTime source, int index, ProtocolVersion protocolVersion) { if (index == 0) { long millis = source.getMillis(); return bigint().serializeNoBoxing(millis, protocolVersion); } if (index == 1) { return varchar().serialize(source.getZone().getID(), protocolVersion); } throw new IndexOutOfBoundsException("Tuple index out of bounds. " + index); } @Override protected DateTime deserializeAndSetField(ByteBuffer input, DateTime target, int index, ProtocolVersion protocolVersion) { if (index == 0) { long millis = bigint().deserializeNoBoxing(input, protocolVersion); return new DateTime(millis); } if (index == 1) { String zoneId = varchar().deserialize(input, protocolVersion); return target.withZone(DateTimeZone.forID(zoneId)); } throw new IndexOutOfBoundsException("Tuple index out of bounds. " + index); } @Override protected String formatField(DateTime value, int index) { if (index == 0) { return quote(printer.print(value)); } if (index == 1) { return quote(value.getZone().getID()); } throw new IndexOutOfBoundsException("Tuple index out of bounds. " + index); } @Override protected DateTime parseAndSetField(String input, DateTime target, int index) { if (index == 0) { // strip enclosing single quotes, if any if (ParseUtils.isQuoted(input)) input = ParseUtils.unquote(input); if (isLongLiteral(input)) { try { long millis = Long.parseLong(input); return new DateTime(millis); } catch (NumberFormatException e) { throw new InvalidTypeException( String.format("Cannot parse timestamp value from \"%s\"", input)); } } try { return parser.parseDateTime(input); } catch (RuntimeException e) { throw new InvalidTypeException(String.format("Cannot parse timestamp value from \"%s\"", target)); } } if (index == 1) { String zoneId = varchar().parse(input); // Joda time does not recognize "Z" if ("Z".equals(zoneId)) return target.withZone(DateTimeZone.UTC); return target.withZone(DateTimeZone.forID(zoneId)); } throw new IndexOutOfBoundsException("Tuple index out of bounds. " + index); } }