/*
* Copyright 2004 The Apache Software Foundation
*
* 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.
*/
using System;
using PrefixQueryLucene.Net.Search.PrefixQuery;
using RangeQueryLucene.Net.Search.RangeQuery;
namespace Lucene.Net.Documents{
/// <summary> Provides support for converting dates to strings and vice-versa.
/// The strings are structured so that lexicographic sorting orders by date,
/// which makes them suitable for use as field values and search terms.
///
/// <P>Note that this class saves dates with millisecond granularity,
/// which is bad for {@link RangeQuery} and {@link PrefixQuery}, as those
/// queries are expanded to a BooleanQuery with a potentially large number
/// of terms when searching. Thus you might want to use
/// {@link DateTools} instead.
///
/// <P>
/// Note: dates before 1970 cannot be used, and therefore cannot be
/// indexed when using this class. See {@link DateTools} for an
/// alternative without such a limitation.
///
/// </summary>
/// <deprecated> If you build a new index, use {@link DateTools} instead. For
/// existing indices you can continue using this class, as it will not be
/// removed in the near future despite being deprecated.
/// </deprecated>
public class DateField
{
private DateField()
{
}
// make date strings long enough to last a millenium
private static int DATE_LEN = System.Convert.ToString(
1000L * 365 * 24 * 60 * 60 * 1000, 36).Length;
public static System.String MIN_DATE_STRING()
{
return TimeToString(0);
}
public static System.String MAX_DATE_STRING()
{
char[] buffer = new char[DATE_LEN];
char c = SupportClass.Character.ForDigit(36 - 1, SupportClass.Character.MAX_RADIX);
for (int i = 0; i < DATE_LEN; i++)
buffer[i] = c;
return new System.String(buffer);
}
/// <summary> Converts a Date to a string suitable for indexing.</summary>
/// <throws> RuntimeException if the date specified in the </throws>
/// <summary> method argument is before 1970
/// </summary>
public static System.String DateToString(System.DateTime date)
{
TimeSpan ts = date.Subtract(new DateTime(1970, 1, 1));
ts = ts.Subtract(TimeZone.CurrentTimeZone.GetUtcOffset(date));
return TimeToString(ts.Ticks / TimeSpan.TicksPerMillisecond);
}
/// <summary> Converts a millisecond time to a string suitable for indexing.</summary>
/// <throws> RuntimeException if the time specified in the </throws>
/// <summary> method argument is negative, that is, before 1970
/// </summary>
public static System.String TimeToString(long time)
{
if (time < 0)
throw new System.SystemException("time too early");
System.String s = SupportClass.Number.ToString(time, SupportClass.Number.MAX_RADIX);
if (s.Length > DATE_LEN)
throw new System.SystemException("time too late");
// Pad with leading zeros
if (s.Length < DATE_LEN)
{
System.Text.StringBuilder sb = new System.Text.StringBuilder(s);
while (sb.Length < DATE_LEN)
sb.Insert(0, 0);
s = sb.ToString();
}
return s;
}
/// <summary>Converts a string-encoded date into a millisecond time. </summary>
public static long StringToTime(System.String s)
{
return SupportClass.Number.Parse(s, SupportClass.Number.MAX_RADIX);
}
/// <summary>Converts a string-encoded date into a Date object. </summary>
public static System.DateTime StringToDate(System.String s)
{
return new System.DateTime(StringToTime(s));
// {{Aroush-1.9}} Will the line above do it or do we need the lines below?!
/*
long ticks = StringToTime(s) * TimeSpan.TicksPerMillisecond;
System.DateTime date = new System.DateTime(1970, 1, 1);
date = date.AddTicks(ticks);
date = date.Add(TimeZone.CurrentTimeZone.GetUtcOffset(date));
return date;
*/
}
}
}
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