Java tutorial
/* * * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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.github.cassandra.jdbc.provider.datastax.codecs; import com.datastax.driver.core.DataType; import com.datastax.driver.core.ProtocolVersion; import com.datastax.driver.core.TypeCodec; import org.joda.time.Days; import org.joda.time.LocalDate; import org.joda.time.format.DateTimeFormat; import org.joda.time.format.DateTimeFormatter; import java.nio.ByteBuffer; import static com.datastax.driver.core.CodecUtils.fromSignedToUnsignedInt; import static com.datastax.driver.core.CodecUtils.fromUnsignedToSignedInt; import static com.datastax.driver.core.ParseUtils.*; import static org.joda.time.Days.daysBetween; public class StringDateCodec extends TypeCodec<String> { public static final StringDateCodec instance = new StringDateCodec(); private static final LocalDate EPOCH = new LocalDate(1970, 1, 1); private static final DateTimeFormatter FORMATTER = DateTimeFormat.forPattern("yyyy-MM-dd").withZoneUTC(); private StringDateCodec() { super(DataType.date(), String.class); } @Override public ByteBuffer serialize(String value, ProtocolVersion protocolVersion) { if (value == null) return null; Days days = daysBetween(EPOCH, LocalDate.parse(value)); int unsigned = fromSignedToUnsignedInt(days.getDays()); return cint().serializeNoBoxing(unsigned, protocolVersion); } @Override public String deserialize(ByteBuffer bytes, ProtocolVersion protocolVersion) { if (bytes == null || bytes.remaining() == 0) return null; int unsigned = cint().deserializeNoBoxing(bytes, protocolVersion); int signed = fromUnsignedToSignedInt(unsigned); return FORMATTER.print(EPOCH.plusDays(signed)); } @Override public String format(String value) { return value == null ? "NULL" : quote(value); } @Override public String parse(String value) { if (value == null || value.isEmpty() || value.equalsIgnoreCase("NULL")) return null; // single quotes are optional for long literals, mandatory for date patterns // strip enclosing single quotes, if any if (isQuoted(value)) { value = unquote(value); } return value; } }