Interval.java
/*
* Copyright (c) 2007-present, Stephen Colebourne & Michael Nascimento Santos
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* * Neither the name of JSR-310 nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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package org.threeten.extra;
import java.io.Serializable;
import java.time.DateTimeException;
import java.time.Duration;
import java.time.Instant;
import java.time.LocalDateTime;
import java.time.OffsetDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;
import java.time.format.DateTimeParseException;
import java.time.temporal.TemporalAccessor;
import java.util.Objects;
import org.joda.convert.FromString;
import org.joda.convert.ToString;
/**
* An immutable interval of time between two instants.
* <p>
* An interval represents the time on the time-line between two {@link Instant}s.
* The class stores the start and end instants, with the start inclusive and the end exclusive.
* The end instant is always greater than or equal to the start instant.
* <p>
* The {@link Duration} of an interval can be obtained, but is a separate concept.
* An interval is connected to the time-line, whereas a duration is not.
* <p>
* Intervals are not comparable. To compare the length of two intervals, it is
* generally recommended to compare their durations.
*
* <h3>Implementation Requirements:</h3>
* This class is immutable and thread-safe.
* <p>
* This class must be treated as a value type. Do not synchronize, rely on the
* identity hash code or use the distinction between equals() and ==.
*/
public final class Interval
implements Serializable {
/**
* An interval over the whole time-line.
*/
public static final Interval ALL = new Interval(Instant.MIN, Instant.MAX);
/**
* Serialization version.
*/
private static final long serialVersionUID = 8375285238652L;
/**
* The start instant (inclusive).
*/
private final Instant start;
/**
* The end instant (exclusive).
*/
private final Instant end;
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code Interval} from the start and end instant.
* <p>
* The end instant must not be before the start instant.
*
* @param startInclusive the start instant, inclusive, {@link Instant#MIN} treated as unbounded, not null
* @param endExclusive the end instant, exclusive, {@link Instant#MAX} treated as unbounded, not null
* @return the half-open interval, not null
* @throws DateTimeException if the end is before the start
*/
public static Interval of(Instant startInclusive, Instant endExclusive) {
Objects.requireNonNull(startInclusive, "startInclusive");
Objects.requireNonNull(endExclusive, "endExclusive");
if (endExclusive.isBefore(startInclusive)) {
throw new DateTimeException("End instant must be equal or after start instant");
}
return new Interval(startInclusive, endExclusive);
}
/**
* Obtains an instance of {@code Interval} from the start and a duration.
* <p>
* The end instant is calculated as the start plus the duration.
* The duration must not be negative.
*
* @param startInclusive the start instant, inclusive, not null
* @param duration the duration from the start to the end, not null
* @return the interval, not null
* @throws DateTimeException if the end is before the start,
* or if the duration addition cannot be made
* @throws ArithmeticException if numeric overflow occurs when adding the duration
*/
public static Interval of(Instant startInclusive, Duration duration) {
Objects.requireNonNull(startInclusive, "startInclusive");
Objects.requireNonNull(duration, "duration");
if (duration.isNegative()) {
throw new DateTimeException("Duration must not be negative");
}
return new Interval(startInclusive, startInclusive.plus(duration));
}
/**
* Obtains an instance of {@code Interval} from the duration and the end.
* <p>
* The start instant is calculated as the end minus the duration.
* The duration must not be negative.
*
* @param duration the duration from the start to the end, not null
* @param endExclusive the end instant, exclusive, not null
* @return the interval, not null
* @throws DateTimeException if the end is before the start,
* or if the duration addition cannot be made
* @throws ArithmeticException if numeric overflow occurs when subtracting the duration
*/
public static Interval of(Duration duration, Instant endExclusive) {
Objects.requireNonNull(duration, "duration");
Objects.requireNonNull(endExclusive, "endExclusive");
if (duration.isNegative()) {
throw new DateTimeException("Duration must not be negative");
}
return new Interval(endExclusive.minus(duration), endExclusive);
}
/**
* Obtains an instance of {@code Interval} with the specified start instant and unbounded end.
*
* @param startInclusive the start instant, inclusive, not null
* @return a new {@code Instant} with the specified start instant.
*/
public static Interval startingAt(Instant startInclusive) {
Objects.requireNonNull(startInclusive, "startInclusive");
return Interval.ALL.withStart(startInclusive);
}
/**
* Obtains an instance of {@code Interval} with unbounded start and the specified end instant.
*
* @param endExclusive the end instant, exclusive, not null
* @return a new {@code Instant} with the specified end instant.
*/
public static Interval endingAt(Instant endExclusive) {
Objects.requireNonNull(endExclusive, "endExclusive");
return Interval.ALL.withEnd(endExclusive);
}
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code Interval} from a text string such as
* {@code 2007-12-03T10:15:30Z/2007-12-04T10:15:30Z}, where the end instant is exclusive.
* <p>
* The string must consist of one of the following four formats:
* <ul>
* <li>a representations of an {@link OffsetDateTime}, followed by a forward slash,
* followed by a representation of a {@link OffsetDateTime}
* <li>a representations of an {@link OffsetDateTime}, followed by a forward slash,
* followed by a representation of a {@link LocalDateTime}, where the end offset is implied.
* <li>a representation of an {@link OffsetDateTime}, followed by a forward slash,
* followed by a representation of a {@link PeriodDuration}
* <li>a representation of a {@link PeriodDuration}, followed by a forward slash,
* followed by a representation of an {@link OffsetDateTime}
* </ul>
* <p>
* ISO-8601 supports a very wide range of possible inputs, many of which are not supported here.
* For example, basic format, week-based dates, ordinal dates and date-style period formats are not supported.
*
* @param text the text to parse, not null
* @return the parsed interval, not null
* @throws DateTimeParseException if the text cannot be parsed
*/
@FromString
public static Interval parse(CharSequence text) {
Objects.requireNonNull(text, "text");
for (int i = 0; i < text.length(); i++) {
if (text.charAt(i) == '/') {
return parseSplit(text.subSequence(0, i), text.subSequence(i + 1, text.length()));
}
}
throw new DateTimeParseException("Interval cannot be parsed, no forward slash found", text, 0);
}
private static Interval parseSplit(CharSequence startStr, CharSequence endStr) {
char firstChar = startStr.charAt(0);
if (firstChar == 'P' || firstChar == 'p') {
// duration followed by instant
PeriodDuration amount = PeriodDuration.parse(startStr);
try {
OffsetDateTime end = OffsetDateTime.parse(endStr);
return Interval.of(end.minus(amount).toInstant(), end.toInstant());
} catch (DateTimeParseException ex) {
// handle case where Instant is outside the bounds of OffsetDateTime
Instant end = Instant.parse(endStr);
// addition of PeriodDuration only supported by OffsetDateTime,
// but to make that work need to move point being subtracted from closer to EPOCH
long move = end.isBefore(Instant.EPOCH) ? 1000 * 86400 : -1000 * 86400;
Instant start = end.plusSeconds(move).atOffset(ZoneOffset.UTC).minus(amount).toInstant().minusSeconds(move);
return Interval.of(start, end);
}
}
// instant followed by instant or duration
OffsetDateTime start;
try {
start = OffsetDateTime.parse(startStr);
} catch (DateTimeParseException ex) {
return parseStartExtended(startStr, endStr);
}
if (endStr.length() > 0) {
char c = endStr.charAt(0);
if (c == 'P' || c == 'p') {
PeriodDuration amount = PeriodDuration.parse(endStr);
return Interval.of(start.toInstant(), start.plus(amount).toInstant());
}
}
return parseEndDateTime(start.toInstant(), start.getOffset(), endStr);
}
// handle case where Instant is outside the bounds of OffsetDateTime
private static Interval parseStartExtended(CharSequence startStr, CharSequence endStr) {
Instant start = Instant.parse(startStr);
if (endStr.length() > 0) {
char c = endStr.charAt(0);
if (c == 'P' || c == 'p') {
PeriodDuration amount = PeriodDuration.parse(endStr);
// addition of PeriodDuration only supported by OffsetDateTime,
// but to make that work need to move point being added to closer to EPOCH
long move = start.isBefore(Instant.EPOCH) ? 1000 * 86400 : -1000 * 86400;
Instant end = start.plusSeconds(move).atOffset(ZoneOffset.UTC).plus(amount).toInstant().minusSeconds(move);
return Interval.of(start, end);
}
}
// infer offset from start if not specified by end
return parseEndDateTime(start, ZoneOffset.UTC, endStr);
}
// parse when there are two date-times
private static Interval parseEndDateTime(Instant start, ZoneOffset offset, CharSequence endStr) {
try {
TemporalAccessor temporal = DateTimeFormatter.ISO_DATE_TIME.parseBest(endStr, OffsetDateTime::from, LocalDateTime::from);
if (temporal instanceof OffsetDateTime) {
OffsetDateTime odt = (OffsetDateTime) temporal;
return Interval.of(start, odt.toInstant());
} else {
// infer offset from start if not specified by end
LocalDateTime ldt = (LocalDateTime) temporal;
return Interval.of(start, ldt.toInstant(offset));
}
} catch (DateTimeParseException ex) {
Instant end = Instant.parse(endStr);
return Interval.of(start, end);
}
}
//-----------------------------------------------------------------------
/**
* Constructor.
*
* @param startInclusive the start instant, inclusive, validated not null
* @param endExclusive the end instant, exclusive, validated not null
*/
private Interval(Instant startInclusive, Instant endExclusive) {
this.start = startInclusive;
this.end = endExclusive;
}
//-----------------------------------------------------------------------
/**
* Gets the start of this time interval, inclusive.
* <p>
* This will return {@link Instant#MIN} if the range is unbounded at the start.
* In this case, the range includes all dates into the far-past.
*
* @return the start of the time interval
*/
public Instant getStart() {
return start;
}
/**
* Gets the end of this time interval, exclusive.
* <p>
* This will return {@link Instant#MAX} if the range is unbounded at the end.
* In this case, the range includes all dates into the far-future.
*
* @return the end of the time interval, exclusive
*/
public Instant getEnd() {
return end;
}
//-----------------------------------------------------------------------
/**
* Checks if the range is empty.
* <p>
* An empty range occurs when the start date equals the inclusive end date.
*
* @return true if the range is empty
*/
public boolean isEmpty() {
return start.equals(end);
}
/**
* Checks if the start of the interval is unbounded.
*
* @return true if start is unbounded
*/
public boolean isUnboundedStart() {
return start.equals(Instant.MIN);
}
/**
* Checks if the end of the interval is unbounded.
*
* @return true if end is unbounded
*/
public boolean isUnboundedEnd() {
return end.equals(Instant.MAX);
}
//-----------------------------------------------------------------------
/**
* Returns a copy of this range with the specified start instant.
*
* @param start the start instant for the new interval, not null
* @return an interval with the end from this interval and the specified start
* @throws DateTimeException if the resulting interval has end before start
*/
public Interval withStart(Instant start) {
return Interval.of(start, end);
}
/**
* Returns a copy of this range with the specified end instant.
*
* @param end the end instant for the new interval, not null
* @return an interval with the start from this interval and the specified end
* @throws DateTimeException if the resulting interval has end before start
*/
public Interval withEnd(Instant end) {
return Interval.of(start, end);
}
//-----------------------------------------------------------------------
/**
* Checks if this interval encloses the specified interval.
* <p>
* This checks if the bounds of the specified interval are within the bounds of this interval.
* An empty interval encloses itself.
*
* @param other the other interval, not null
* @return true if this interval contains the other interval
*/
public boolean encloses(Interval other) {
Objects.requireNonNull(other, "other");
return start.compareTo(other.start) <= 0 && other.end.compareTo(end) <= 0;
}
/**
* Checks if this interval abuts the specified interval.
* <p>
* The result is true if the end of this interval is the start of the other, or vice versa.
* An empty interval does not abut itself.
*
* @param other the other interval, not null
* @return true if this interval abuts the other interval
*/
public boolean abuts(Interval other) {
Objects.requireNonNull(other, "other");
return end.equals(other.start) ^ start.equals(other.end);
}
/**
* Checks if this interval is connected to the specified interval.
* <p>
* The result is true if the two intervals have an enclosed interval in common, even if that interval is empty.
* An empty interval is connected to itself.
* <p>
* This is equivalent to {@code (overlaps(other) || abuts(other))}.
*
* @param other the other interval, not null
* @return true if this interval is connected to the other interval
*/
public boolean isConnected(Interval other) {
Objects.requireNonNull(other, "other");
return this.equals(other) || (start.compareTo(other.end) <= 0 && other.start.compareTo(end) <= 0);
}
/**
* Checks if this interval overlaps the specified interval.
* <p>
* The result is true if the two intervals share some part of the time-line.
* An empty interval overlaps itself.
* <p>
* This is equivalent to {@code (isConnected(other) && !abuts(other))}.
*
* @param other the time interval to compare to, null means a zero length interval now
* @return true if the time intervals overlap
*/
public boolean overlaps(Interval other) {
Objects.requireNonNull(other, "other");
return other.equals(this) || (start.compareTo(other.end) < 0 && other.start.compareTo(end) < 0);
}
//-----------------------------------------------------------------------
/**
* Calculates the interval that is the intersection of this interval and the specified interval.
* <p>
* This finds the intersection of two intervals.
* This throws an exception if the two intervals are not {@linkplain #isConnected(Interval) connected}.
*
* @param other the other interval to check for, not null
* @return the interval that is the intersection of the two intervals
* @throws DateTimeException if the intervals do not connect
*/
public Interval intersection(Interval other) {
Objects.requireNonNull(other, "other");
if (isConnected(other) == false) {
throw new DateTimeException("Intervals do not connect: " + this + " and " + other);
}
int cmpStart = start.compareTo(other.start);
int cmpEnd = end.compareTo(other.end);
if (cmpStart >= 0 && cmpEnd <= 0) {
return this;
} else if (cmpStart <= 0 && cmpEnd >= 0) {
return other;
} else {
Instant newStart = (cmpStart >= 0 ? start : other.start);
Instant newEnd = (cmpEnd <= 0 ? end : other.end);
return Interval.of(newStart, newEnd);
}
}
/**
* Calculates the interval that is the union of this interval and the specified interval.
* <p>
* This finds the union of two intervals.
* This throws an exception if the two intervals are not {@linkplain #isConnected(Interval) connected}.
*
* @param other the other interval to check for, not null
* @return the interval that is the union of the two intervals
* @throws DateTimeException if the intervals do not connect
*/
public Interval union(Interval other) {
Objects.requireNonNull(other, "other");
if (isConnected(other) == false) {
throw new DateTimeException("Intervals do not connect: " + this + " and " + other);
}
int cmpStart = start.compareTo(other.start);
int cmpEnd = end.compareTo(other.end);
if (cmpStart >= 0 && cmpEnd <= 0) {
return other;
} else if (cmpStart <= 0 && cmpEnd >= 0) {
return this;
} else {
Instant newStart = (cmpStart >= 0 ? other.start : start);
Instant newEnd = (cmpEnd <= 0 ? other.end : end);
return Interval.of(newStart, newEnd);
}
}
/**
* Calculates the smallest interval that encloses this interval and the specified interval.
* <p>
* The result of this method will {@linkplain #encloses(Interval) enclose}
* this interval and the specified interval.
*
* @param other the other interval to check for, not null
* @return the interval that spans the two intervals
*/
public Interval span(Interval other) {
Objects.requireNonNull(other, "other");
int cmpStart = start.compareTo(other.start);
int cmpEnd = end.compareTo(other.end);
Instant newStart = (cmpStart >= 0 ? other.start : start);
Instant newEnd = (cmpEnd <= 0 ? other.end : end);
return Interval.of(newStart, newEnd);
}
//-------------------------------------------------------------------------
/**
* Checks if this interval is after the specified interval.
* <p>
* The result is true if this interval starts after the end of the specified interval.
* Since intervals do not include their end points, this will return true if the
* two intervals abut.
* An empty interval behaves as though it is an instant for comparison purposes.
*
* @param interval the other interval to compare to, not null
* @return true if this interval is after the specified interval
*/
public boolean isAfter(Interval interval) {
return start.compareTo(interval.end) >= 0 && !interval.equals(this);
}
/**
* Checks if this interval is before the specified interval.
* <p>
* The result is true if this interval ends before the start of the specified interval.
* Since intervals do not include their end points, this will return true if the
* two intervals abut.
* An empty interval behaves as though it is an instant for comparison purposes.
*
* @param interval the other interval to compare to, not null
* @return true if this interval is before the specified interval
*/
public boolean isBefore(Interval interval) {
return end.compareTo(interval.start) <= 0 && !interval.equals(this);
}
//-------------------------------------------------------------------------
/**
* Checks if this interval starts on or before the specified instant.
* <p>
* This method compares the start of the interval to the instant.
* An interval with an unbounded start is considered to start at {@code Instant.MIN}.
*
* @param instant the instant, not null
* @return true if this interval starts before the instant
*/
public boolean startsBefore(Instant instant) {
Objects.requireNonNull(instant, "instant");
return start.compareTo(instant) < 0;
}
/**
* Checks if this interval starts at or before the specified instant.
* <p>
* This method compares the start of the interval to the instant.
* An interval with an unbounded start is considered to start at {@code Instant.MIN}.
*
* @param instant the instant, not null
* @return true if this interval starts at or before the instant
*/
public boolean startsAtOrBefore(Instant instant) {
Objects.requireNonNull(instant, "instant");
return start.compareTo(instant) <= 0;
}
/**
* Checks if this interval starts on or after the specified instant.
* <p>
* This method compares the start of the interval to the instant.
* An interval with an unbounded start is considered to start at {@code Instant.MIN}.
*
* @param instant the instant, not null
* @return true if this interval starts after the instant
*/
public boolean startsAfter(Instant instant) {
Objects.requireNonNull(instant, "instant");
return start.compareTo(instant) > 0;
}
/**
* Checks if this interval starts at or after the specified instant.
* <p>
* This method compares the start of the interval to the instant.
* An interval with an unbounded start is considered to start at {@code Instant.MIN}.
*
* @param instant the instant, not null
* @return true if this interval starts at or after the instant
*/
public boolean startsAtOrAfter(Instant instant) {
Objects.requireNonNull(instant, "instant");
return start.compareTo(instant) >= 0;
}
//-------------------------------------------------------------------------
/**
* Checks if this interval ends before the specified instant.
* <p>
* This method compares the end of the interval to the instant.
* An interval with an unbounded end is considered to end after {@code Instant.MAX}.
*
* @param instant the instant, not null
* @return true if this interval ends before the instant
*/
public boolean endsBefore(Instant instant) {
Objects.requireNonNull(instant, "instant");
return end.compareTo(instant) < 0 && !isUnboundedEnd();
}
/**
* Checks if this interval ends at or before the specified instant.
* <p>
* This method compares the end of the interval to the instant.
* An interval with an unbounded end is considered to end after {@code Instant.MAX}.
*
* @param instant the instant, not null
* @return true if this interval ends at or before the instant
*/
public boolean endsAtOrBefore(Instant instant) {
Objects.requireNonNull(instant, "instant");
return end.compareTo(instant) <= 0 && !isUnboundedEnd();
}
/**
* Checks if this interval ends after the specified instant.
* <p>
* This method compares the end of the interval to the instant.
* An interval with an unbounded end is considered to end after {@code Instant.MAX}.
*
* @param instant the instant, not null
* @return true if this interval ends after the instant
*/
public boolean endsAfter(Instant instant) {
Objects.requireNonNull(instant, "instant");
return end.compareTo(instant) > 0 || isUnboundedEnd();
}
/**
* Checks if this interval ends after the specified instant.
* <p>
* This method compares the end of the interval to the instant.
* An interval with an unbounded end is considered to end after {@code Instant.MAX}.
*
* @param instant the instant, not null
* @return true if this interval ends at or after the instant
*/
public boolean endsAtOrAfter(Instant instant) {
Objects.requireNonNull(instant, "instant");
return end.compareTo(instant) >= 0 || isUnboundedEnd();
}
//-------------------------------------------------------------------------
/**
* Checks if this interval contains the specified instant.
* <p>
* This checks if the specified instant is within the bounds of this interval.
* If this interval has an unbounded start then {@code contains(Instant#MIN)} returns true.
* If this interval has an unbounded end then {@code contains(Instant#MAX)} returns true.
* Otherwise, if this interval is empty then this method returns false.
* <p>
* This is equivalent to {@link #startsAtOrBefore(Instant)} {@code &&} {@link #endsAfter(Instant)}.
*
* @param instant the instant, not null
* @return true if this interval contains the instant
*/
public boolean contains(Instant instant) {
return startsAtOrBefore(instant) && endsAfter(instant);
}
/**
* Checks if this interval is after the specified instant.
* <p>
* The result is true if this interval starts after the specified instant.
* An empty interval behaves as though it is an instant for comparison purposes.
* <p>
* This is equivalent to {@link #startsAfter(Instant)}.
*
* @param instant the other instant to compare to, not null
* @return true if the start of this interval is after the specified instant
*/
public boolean isAfter(Instant instant) {
return startsAfter(instant);
}
/**
* Checks if this interval is before the specified instant.
* <p>
* The result is true if this interval ends before the specified instant.
* Since intervals do not include their end points, this will return true if the
* instant equals the end of the interval.
* An empty interval behaves as though it is an instant for comparison purposes.
* <p>
* This is equivalent to {@link #endsAtOrBefore(Instant)} {@code &&} {@link #startsBefore(Instant)}.
*
* @param instant the other instant to compare to, not null
* @return true if the end of this interval is before or equal to the specified instant
*/
public boolean isBefore(Instant instant) {
return endsAtOrBefore(instant) && startsBefore(instant);
}
//-----------------------------------------------------------------------
/**
* Obtains the duration of this interval.
* <p>
* An {@code Interval} is associated with two specific instants on the time-line.
* A {@code Duration} is simply an amount of time, separate from the time-line.
*
* @return the duration of the time interval
* @throws ArithmeticException if the calculation exceeds the capacity of {@code Duration}
*/
public Duration toDuration() {
return Duration.between(start, end);
}
//-----------------------------------------------------------------------
/**
* Checks if this interval is equal to another interval.
* <p>
* Compares this {@code Interval} with another ensuring that the two instants are the same.
* Only objects of type {@code Interval} are compared, other types return false.
*
* @param obj the object to check, null returns false
* @return true if this is equal to the other interval
*/
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj instanceof Interval) {
Interval other = (Interval) obj;
return start.equals(other.start) && end.equals(other.end);
}
return false;
}
/**
* A hash code for this interval.
*
* @return a suitable hash code
*/
@Override
public int hashCode() {
return start.hashCode() ^ end.hashCode();
}
//-----------------------------------------------------------------------
/**
* Outputs this interval as a {@code String}, such as {@code 2007-12-03T10:15:30/2007-12-04T10:15:30}.
* <p>
* The output will be the ISO-8601 format formed by combining the
* {@code toString()} methods of the two instants, separated by a forward slash.
*
* @return a string representation of this instant, not null
*/
@Override
@ToString
public String toString() {
return start.toString() + '/' + end.toString();
}
}