TimestampString.java
/*
* 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 org.apache.calcite.util;
import org.apache.calcite.avatica.util.DateTimeUtils;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.google.common.base.Strings;
import org.checkerframework.checker.nullness.qual.Nullable;
import java.util.Calendar;
import java.util.TimeZone;
import java.util.regex.Pattern;
import static com.google.common.base.Preconditions.checkArgument;
import static org.apache.calcite.util.DateTimeStringUtils.ymdhms;
import static java.lang.Math.floorMod;
/**
* Timestamp literal.
*
* <p>Immutable, internally represented as a string (in ISO format),
* and can support unlimited precision (milliseconds, nanoseconds).
*/
public class TimestampString implements Comparable<TimestampString> {
private static final Pattern PATTERN =
Pattern.compile("[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]"
+ " "
+ "[0-9][0-9]:[0-9][0-9]:[0-9][0-9](\\.[0-9]*[1-9])?");
/** The allowed format of input strings is slightly more flexible than
* normalized strings. Input strings can have trailing zeros in the fractional
* seconds. */
private static final Pattern INPUT_PATTERN =
Pattern.compile("[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]"
+ " "
+ "[0-9][0-9]:[0-9][0-9]:[0-9][0-9](\\.[0-9]+)?");
/** The Unix epoch. */
public static final TimestampString EPOCH =
new TimestampString(1970, 1, 1, 0, 0, 0);
final String v;
/** Creates a TimeString. */
public TimestampString(String v) {
this.v = normalize(v);
}
/** Creates a TimestampString for year, month, day, hour, minute, second,
* millisecond values. */
public TimestampString(int year, int month, int day, int h, int m, int s) {
this(ymdhms(new StringBuilder(), year, month, day, h, m, s).toString());
}
/** Sets the fraction field of a {@code TimestampString} to a given number
* of milliseconds. Nukes the value set via {@link #withNanos}.
*
* <p>For example,
* {@code new TimestampString(1970, 1, 1, 2, 3, 4).withMillis(56)}
*
* @throws IllegalArgumentException if millis is outside the allowed range */
public TimestampString withMillis(int millis) {
checkArgument(millis >= 0 && millis < 1000);
return withFraction(DateTimeStringUtils.pad(3, millis));
}
/** Sets the fraction field of a {@code TimestampString} to a given number
* of nanoseconds. Nukes the value set via {@link #withMillis(int)}.
*
* <p>For example,
* {@code new TimestampString(1970, 1, 1, 2, 3, 4).withNanos(56789)}
* yields {@code TIMESTAMP '1970-01-01 02:03:04.000056789'}.
*
* @throws IllegalArgumentException if nanos is outside the allowed range */
public TimestampString withNanos(int nanos) {
checkArgument(nanos >= 0 && nanos < 1000000000);
return withFraction(DateTimeStringUtils.pad(9, nanos));
}
/** Sets the fraction field of a {@code TimestampString}.
* The precision is determined by the number of leading zeros.
* Trailing zeros are stripped.
*
* <p>For example,
* {@code new TimestampString(1970, 1, 1, 2, 3, 4).withFraction("00506000")}
* yields {@code TIMESTAMP '1970-01-01 02:03:04.00506'}. */
public TimestampString withFraction(String fraction) {
String v = this.v;
int i = v.indexOf('.');
if (i >= 0) {
v = v.substring(0, i);
}
while (fraction.endsWith("0")) {
fraction = fraction.substring(0, fraction.length() - 1);
}
if (!fraction.isEmpty()) {
v = v + "." + fraction;
}
return new TimestampString(v);
}
private static String normalize(String v) {
checkArgument(INPUT_PATTERN.matcher(v).matches(), v);
// Remove trailing zeros in the fractional seconds
if (v.indexOf('.') >= 0) {
while (v.endsWith("0")) {
v = v.substring(0, v.length() - 1);
}
}
checkArgument(PATTERN.matcher(v).matches(), v);
return v;
}
@Override public String toString() {
return v;
}
@Override public boolean equals(@Nullable Object o) {
// The value is in canonical form (no trailing zeros).
return o == this
|| o instanceof TimestampString
&& ((TimestampString) o).v.equals(v);
}
@Override public int hashCode() {
return v.hashCode();
}
@Override public int compareTo(TimestampString o) {
return v.compareTo(o.v);
}
/** Creates a TimestampString from a Calendar. */
public static TimestampString fromCalendarFields(Calendar calendar) {
return new TimestampString(
calendar.get(Calendar.YEAR),
calendar.get(Calendar.MONTH) + 1,
calendar.get(Calendar.DAY_OF_MONTH),
calendar.get(Calendar.HOUR_OF_DAY),
calendar.get(Calendar.MINUTE),
calendar.get(Calendar.SECOND))
.withMillis(calendar.get(Calendar.MILLISECOND));
}
/** Returns this value rounded to {@code precision} decimal digits after the
* point.
*
* <p>Uses rounding mode {@link java.math.RoundingMode#DOWN}. */
public TimestampString round(int precision) {
checkArgument(precision >= 0);
int targetLength = 20 + precision;
if (v.length() <= targetLength) {
return this;
}
String v = this.v.substring(0, targetLength);
while (v.length() >= 20 && (v.endsWith("0") || v.endsWith("."))) {
v = v.substring(0, v.length() - 1);
}
return new TimestampString(v);
}
/** Returns the number of milliseconds since the epoch. */
public long getMillisSinceEpoch() {
final int year = Integer.valueOf(v.substring(0, 4));
final int month = Integer.valueOf(v.substring(5, 7));
final int day = Integer.valueOf(v.substring(8, 10));
final int h = Integer.valueOf(v.substring(11, 13));
final int m = Integer.valueOf(v.substring(14, 16));
final int s = Integer.valueOf(v.substring(17, 19));
final int ms = getMillisInSecond();
final int d = DateTimeUtils.ymdToUnixDate(year, month, day);
return d * DateTimeUtils.MILLIS_PER_DAY
+ h * DateTimeUtils.MILLIS_PER_HOUR
+ m * DateTimeUtils.MILLIS_PER_MINUTE
+ s * DateTimeUtils.MILLIS_PER_SECOND
+ ms;
}
private int getMillisInSecond() {
switch (v.length()) {
case 19: // "1999-12-31 12:34:56"
return 0;
case 21: // "1999-12-31 12:34:56.7"
return Integer.valueOf(v.substring(20)) * 100;
case 22: // "1999-12-31 12:34:56.78"
return Integer.valueOf(v.substring(20)) * 10;
case 23: // "1999-12-31 12:34:56.789"
default: // "1999-12-31 12:34:56.789123456"
return Integer.valueOf(v.substring(20, 23));
}
}
/** Creates a TimestampString that is a given number of milliseconds since
* the epoch. */
@JsonCreator
public static TimestampString fromMillisSinceEpoch(
@JsonProperty("millisSinceEpoch") long millis) {
return new TimestampString(DateTimeUtils.unixTimestampToString(millis))
.withMillis((int) floorMod(millis, 1000L));
}
public Calendar toCalendar() {
return Util.calendar(getMillisSinceEpoch());
}
public Calendar toCalendar(TimeZone timeZone) {
return Util.calendar(getMillisSinceEpoch(), timeZone);
}
/** Converts this TimestampString to a string, truncated or padded with
* zeros to a given precision. */
public String toString(int precision) {
checkArgument(precision >= 0);
final int p = precision();
if (precision < p) {
return round(precision).toString(precision);
}
if (precision > p) {
String s = v;
if (p == 0) {
s += ".";
}
return s + Strings.repeat("0", precision - p);
}
return v;
}
private int precision() {
return v.length() < 20 ? 0 : (v.length() - 20);
}
}