jdk/src/share/classes/java/time/chrono/ChronoLocalDateTime.java
changeset 15658 55b829ca2334
child 16852 60207b2b4b42
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/time/chrono/ChronoLocalDateTime.java	Tue Feb 12 09:25:43 2013 -0800
@@ -0,0 +1,510 @@
+/*
+ * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * This file is available under and governed by the GNU General Public
+ * License version 2 only, as published by the Free Software Foundation.
+ * However, the following notice accompanied the original version of this
+ * file:
+ *
+ * Copyright (c) 2007-2012, 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
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package java.time.chrono;
+
+import static java.time.temporal.ChronoField.EPOCH_DAY;
+import static java.time.temporal.ChronoField.NANO_OF_DAY;
+import static java.time.temporal.ChronoUnit.NANOS;
+
+import java.time.DateTimeException;
+import java.time.Instant;
+import java.time.LocalDateTime;
+import java.time.LocalTime;
+import java.time.ZoneId;
+import java.time.ZoneOffset;
+import java.time.format.DateTimeFormatter;
+import java.time.temporal.ChronoField;
+import java.time.temporal.Queries;
+import java.time.temporal.Temporal;
+import java.time.temporal.TemporalAccessor;
+import java.time.temporal.TemporalAdjuster;
+import java.time.temporal.TemporalAmount;
+import java.time.temporal.TemporalField;
+import java.time.temporal.TemporalQuery;
+import java.time.temporal.TemporalUnit;
+import java.time.zone.ZoneRules;
+import java.util.Comparator;
+import java.util.Objects;
+
+/**
+ * A date-time without a time-zone in an arbitrary chronology, intended
+ * for advanced globalization use cases.
+ * <p>
+ * <b>Most applications should declare method signatures, fields and variables
+ * as {@link LocalDateTime}, not this interface.</b>
+ * <p>
+ * A {@code ChronoLocalDateTime} is the abstract representation of a local date-time
+ * where the {@code Chronology chronology}, or calendar system, is pluggable.
+ * The date-time is defined in terms of fields expressed by {@link TemporalField},
+ * where most common implementations are defined in {@link ChronoField}.
+ * The chronology defines how the calendar system operates and the meaning of
+ * the standard fields.
+ *
+ * <h3>When to use this interface</h3>
+ * The design of the API encourages the use of {@code LocalDateTime} rather than this
+ * interface, even in the case where the application needs to deal with multiple
+ * calendar systems. The rationale for this is explored in detail in {@link ChronoLocalDate}.
+ * <p>
+ * Ensure that the discussion in {@code ChronoLocalDate} has been read and understood
+ * before using this interface.
+ *
+ * <h3>Specification for implementors</h3>
+ * This interface must be implemented with care to ensure other classes operate correctly.
+ * All implementations that can be instantiated must be final, immutable and thread-safe.
+ * Subclasses should be Serializable wherever possible.
+ *
+ * @param <D> the concrete type for the date of this date-time
+ * @since 1.8
+ */
+public interface ChronoLocalDateTime<D extends ChronoLocalDate<D>>
+        extends Temporal, TemporalAdjuster, Comparable<ChronoLocalDateTime<?>> {
+
+    /**
+     * Comparator for two {@code ChronoLocalDateTime} instances ignoring the chronology.
+     * <p>
+     * This method differs from the comparison in {@link #compareTo} in that it
+     * only compares the underlying date and not the chronology.
+     * This allows dates in different calendar systems to be compared based
+     * on the time-line position.
+     *
+     * @see #isAfter
+     * @see #isBefore
+     * @see #isEqual
+     */
+    Comparator<ChronoLocalDateTime<?>> DATE_TIME_COMPARATOR =
+            new Comparator<ChronoLocalDateTime<?>>() {
+        @Override
+        public int compare(ChronoLocalDateTime<?> datetime1, ChronoLocalDateTime<?> datetime2) {
+            int cmp = Long.compare(datetime1.toLocalDate().toEpochDay(), datetime2.toLocalDate().toEpochDay());
+            if (cmp == 0) {
+                cmp = Long.compare(datetime1.toLocalTime().toNanoOfDay(), datetime2.toLocalTime().toNanoOfDay());
+            }
+            return cmp;
+        }
+    };
+
+    /**
+     * Gets the local date part of this date-time.
+     * <p>
+     * This returns a local date with the same year, month and day
+     * as this date-time.
+     *
+     * @return the date part of this date-time, not null
+     */
+    D toLocalDate() ;
+
+    /**
+     * Gets the local time part of this date-time.
+     * <p>
+     * This returns a local time with the same hour, minute, second and
+     * nanosecond as this date-time.
+     *
+     * @return the time part of this date-time, not null
+     */
+    LocalTime toLocalTime();
+
+    @Override   // Override to provide javadoc
+    public boolean isSupported(TemporalField field);
+
+    //-----------------------------------------------------------------------
+    // override for covariant return type
+    /**
+     * {@inheritDoc}
+     * @throws DateTimeException {@inheritDoc}
+     * @throws ArithmeticException {@inheritDoc}
+     */
+    @Override
+    public default ChronoLocalDateTime<D> with(TemporalAdjuster adjuster) {
+        return (ChronoLocalDateTime<D>)(toLocalDate().getChronology().ensureChronoLocalDateTime(Temporal.super.with(adjuster)));
+    }
+
+    /**
+     * {@inheritDoc}
+     * @throws DateTimeException {@inheritDoc}
+     * @throws ArithmeticException {@inheritDoc}
+     */
+    @Override
+    ChronoLocalDateTime<D> with(TemporalField field, long newValue);
+
+    /**
+     * {@inheritDoc}
+     * @throws DateTimeException {@inheritDoc}
+     * @throws ArithmeticException {@inheritDoc}
+     */
+    @Override
+    public default ChronoLocalDateTime<D> plus(TemporalAmount amount) {
+        return (ChronoLocalDateTime<D>)(toLocalDate().getChronology().ensureChronoLocalDateTime(Temporal.super.plus(amount)));
+    }
+
+    /**
+     * {@inheritDoc}
+     * @throws DateTimeException {@inheritDoc}
+     * @throws ArithmeticException {@inheritDoc}
+     */
+    @Override
+    ChronoLocalDateTime<D> plus(long amountToAdd, TemporalUnit unit);
+
+    /**
+     * {@inheritDoc}
+     * @throws DateTimeException {@inheritDoc}
+     * @throws ArithmeticException {@inheritDoc}
+     */
+    @Override
+    public default ChronoLocalDateTime<D> minus(TemporalAmount amount) {
+        return (ChronoLocalDateTime<D>)(toLocalDate().getChronology().ensureChronoLocalDateTime(Temporal.super.minus(amount)));
+    }
+
+    /**
+     * {@inheritDoc}
+     * @throws DateTimeException {@inheritDoc}
+     * @throws ArithmeticException {@inheritDoc}
+     */
+    @Override
+    public default ChronoLocalDateTime<D> minus(long amountToSubtract, TemporalUnit unit) {
+        return (ChronoLocalDateTime<D>)(toLocalDate().getChronology().ensureChronoLocalDateTime(Temporal.super.minus(amountToSubtract, unit)));
+    }
+
+    //-----------------------------------------------------------------------
+    /**
+     * Queries this date-time using the specified query.
+     * <p>
+     * This queries this date-time using the specified query strategy object.
+     * The {@code TemporalQuery} object defines the logic to be used to
+     * obtain the result. Read the documentation of the query to understand
+     * what the result of this method will be.
+     * <p>
+     * The result of this method is obtained by invoking the
+     * {@link java.time.temporal.TemporalQuery#queryFrom(TemporalAccessor)} method on the
+     * specified query passing {@code this} as the argument.
+     *
+     * @param <R> the type of the result
+     * @param query  the query to invoke, not null
+     * @return the query result, null may be returned (defined by the query)
+     * @throws DateTimeException if unable to query (defined by the query)
+     * @throws ArithmeticException if numeric overflow occurs (defined by the query)
+     */
+    @SuppressWarnings("unchecked")
+    @Override
+    public default <R> R query(TemporalQuery<R> query) {
+        if (query == Queries.zoneId() || query == Queries.zone() || query == Queries.offset()) {
+            return null;
+        } else if (query == Queries.localTime()) {
+            return (R) toLocalTime();
+        } else if (query == Queries.chronology()) {
+            return (R) toLocalDate().getChronology();
+        } else if (query == Queries.precision()) {
+            return (R) NANOS;
+        }
+        // inline TemporalAccessor.super.query(query) as an optimization
+        // non-JDK classes are not permitted to make this optimization
+        return query.queryFrom(this);
+    }
+
+    /**
+     * Adjusts the specified temporal object to have the same date and time as this object.
+     * <p>
+     * This returns a temporal object of the same observable type as the input
+     * with the date and time changed to be the same as this.
+     * <p>
+     * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
+     * twice, passing {@link ChronoField#EPOCH_DAY} and
+     * {@link ChronoField#NANO_OF_DAY} as the fields.
+     * <p>
+     * In most cases, it is clearer to reverse the calling pattern by using
+     * {@link Temporal#with(TemporalAdjuster)}:
+     * <pre>
+     *   // these two lines are equivalent, but the second approach is recommended
+     *   temporal = thisLocalDateTime.adjustInto(temporal);
+     *   temporal = temporal.with(thisLocalDateTime);
+     * </pre>
+     * <p>
+     * This instance is immutable and unaffected by this method call.
+     *
+     * @param temporal  the target object to be adjusted, not null
+     * @return the adjusted object, not null
+     * @throws DateTimeException if unable to make the adjustment
+     * @throws ArithmeticException if numeric overflow occurs
+     */
+    @Override
+    public default Temporal adjustInto(Temporal temporal) {
+        return temporal
+                .with(EPOCH_DAY, toLocalDate().toEpochDay())
+                .with(NANO_OF_DAY, toLocalTime().toNanoOfDay());
+    }
+
+    //-----------------------------------------------------------------------
+    /**
+     * Combines this time with a time-zone to create a {@code ChronoZonedDateTime}.
+     * <p>
+     * This returns a {@code ChronoZonedDateTime} formed from this date-time at the
+     * specified time-zone. The result will match this date-time as closely as possible.
+     * Time-zone rules, such as daylight savings, mean that not every local date-time
+     * is valid for the specified zone, thus the local date-time may be adjusted.
+     * <p>
+     * The local date-time is resolved to a single instant on the time-line.
+     * This is achieved by finding a valid offset from UTC/Greenwich for the local
+     * date-time as defined by the {@link ZoneRules rules} of the zone ID.
+     *<p>
+     * In most cases, there is only one valid offset for a local date-time.
+     * In the case of an overlap, where clocks are set back, there are two valid offsets.
+     * This method uses the earlier offset typically corresponding to "summer".
+     * <p>
+     * In the case of a gap, where clocks jump forward, there is no valid offset.
+     * Instead, the local date-time is adjusted to be later by the length of the gap.
+     * For a typical one hour daylight savings change, the local date-time will be
+     * moved one hour later into the offset typically corresponding to "summer".
+     * <p>
+     * To obtain the later offset during an overlap, call
+     * {@link ChronoZonedDateTime#withLaterOffsetAtOverlap()} on the result of this method.
+     *
+     * @param zone  the time-zone to use, not null
+     * @return the zoned date-time formed from this date-time, not null
+     */
+    ChronoZonedDateTime<D> atZone(ZoneId zone);
+
+    //-----------------------------------------------------------------------
+    /**
+     * Converts this date-time to an {@code Instant}.
+     * <p>
+     * This combines this local date-time and the specified offset to form
+     * an {@code Instant}.
+     * <p>
+     * This default implementation calculates from the epoch-day of the date and the
+     * second-of-day of the time.
+     *
+     * @param offset  the offset to use for the conversion, not null
+     * @return an {@code Instant} representing the same instant, not null
+     */
+    public default Instant toInstant(ZoneOffset offset) {
+        return Instant.ofEpochSecond(toEpochSecond(offset), toLocalTime().getNano());
+    }
+
+    /**
+     * Converts this date-time to the number of seconds from the epoch
+     * of 1970-01-01T00:00:00Z.
+     * <p>
+     * This combines this local date-time and the specified offset to calculate the
+     * epoch-second value, which is the number of elapsed seconds from 1970-01-01T00:00:00Z.
+     * Instants on the time-line after the epoch are positive, earlier are negative.
+     * <p>
+     * This default implementation calculates from the epoch-day of the date and the
+     * second-of-day of the time.
+     *
+     * @param offset  the offset to use for the conversion, not null
+     * @return the number of seconds from the epoch of 1970-01-01T00:00:00Z
+     */
+    public default long toEpochSecond(ZoneOffset offset) {
+        Objects.requireNonNull(offset, "offset");
+        long epochDay = toLocalDate().toEpochDay();
+        long secs = epochDay * 86400 + toLocalTime().toSecondOfDay();
+        secs -= offset.getTotalSeconds();
+        return secs;
+    }
+
+    //-----------------------------------------------------------------------
+    /**
+     * Compares this date-time to another date-time, including the chronology.
+     * <p>
+     * The comparison is based first on the underlying time-line date-time, then
+     * on the chronology.
+     * It is "consistent with equals", as defined by {@link Comparable}.
+     * <p>
+     * For example, the following is the comparator order:
+     * <ol>
+     * <li>{@code 2012-12-03T12:00 (ISO)}</li>
+     * <li>{@code 2012-12-04T12:00 (ISO)}</li>
+     * <li>{@code 2555-12-04T12:00 (ThaiBuddhist)}</li>
+     * <li>{@code 2012-12-05T12:00 (ISO)}</li>
+     * </ol>
+     * Values #2 and #3 represent the same date-time on the time-line.
+     * When two values represent the same date-time, the chronology ID is compared to distinguish them.
+     * This step is needed to make the ordering "consistent with equals".
+     * <p>
+     * If all the date-time objects being compared are in the same chronology, then the
+     * additional chronology stage is not required and only the local date-time is used.
+     * <p>
+     * This default implementation performs the comparison defined above.
+     *
+     * @param other  the other date-time to compare to, not null
+     * @return the comparator value, negative if less, positive if greater
+     */
+    @Override
+    public default int compareTo(ChronoLocalDateTime<?> other) {
+        int cmp = toLocalDate().compareTo(other.toLocalDate());
+        if (cmp == 0) {
+            cmp = toLocalTime().compareTo(other.toLocalTime());
+            if (cmp == 0) {
+                cmp = toLocalDate().getChronology().compareTo(other.toLocalDate().getChronology());
+            }
+        }
+        return cmp;
+    }
+
+    /**
+     * Checks if this date-time is after the specified date-time ignoring the chronology.
+     * <p>
+     * This method differs from the comparison in {@link #compareTo} in that it
+     * only compares the underlying date-time and not the chronology.
+     * This allows dates in different calendar systems to be compared based
+     * on the time-line position.
+     * <p>
+     * This default implementation performs the comparison based on the epoch-day
+     * and nano-of-day.
+     *
+     * @param other  the other date-time to compare to, not null
+     * @return true if this is after the specified date-time
+     */
+    public default boolean isAfter(ChronoLocalDateTime<?> other) {
+        long thisEpDay = this.toLocalDate().toEpochDay();
+        long otherEpDay = other.toLocalDate().toEpochDay();
+        return thisEpDay > otherEpDay ||
+            (thisEpDay == otherEpDay && this.toLocalTime().toNanoOfDay() > other.toLocalTime().toNanoOfDay());
+    }
+
+    /**
+     * Checks if this date-time is before the specified date-time ignoring the chronology.
+     * <p>
+     * This method differs from the comparison in {@link #compareTo} in that it
+     * only compares the underlying date-time and not the chronology.
+     * This allows dates in different calendar systems to be compared based
+     * on the time-line position.
+     * <p>
+     * This default implementation performs the comparison based on the epoch-day
+     * and nano-of-day.
+     *
+     * @param other  the other date-time to compare to, not null
+     * @return true if this is before the specified date-time
+     */
+    public default boolean isBefore(ChronoLocalDateTime<?> other) {
+        long thisEpDay = this.toLocalDate().toEpochDay();
+        long otherEpDay = other.toLocalDate().toEpochDay();
+        return thisEpDay < otherEpDay ||
+            (thisEpDay == otherEpDay && this.toLocalTime().toNanoOfDay() < other.toLocalTime().toNanoOfDay());
+    }
+
+    /**
+     * Checks if this date-time is equal to the specified date-time ignoring the chronology.
+     * <p>
+     * This method differs from the comparison in {@link #compareTo} in that it
+     * only compares the underlying date and time and not the chronology.
+     * This allows date-times in different calendar systems to be compared based
+     * on the time-line position.
+     * <p>
+     * This default implementation performs the comparison based on the epoch-day
+     * and nano-of-day.
+     *
+     * @param other  the other date-time to compare to, not null
+     * @return true if the underlying date-time is equal to the specified date-time on the timeline
+     */
+    public default boolean isEqual(ChronoLocalDateTime<?> other) {
+        // Do the time check first, it is cheaper than computing EPOCH day.
+        return this.toLocalTime().toNanoOfDay() == other.toLocalTime().toNanoOfDay() &&
+               this.toLocalDate().toEpochDay() == other.toLocalDate().toEpochDay();
+    }
+
+    /**
+     * Checks if this date-time is equal to another date-time, including the chronology.
+     * <p>
+     * Compares this date-time with another ensuring that the date-time and chronology are the same.
+     *
+     * @param obj  the object to check, null returns false
+     * @return true if this is equal to the other date
+     */
+    @Override
+    boolean equals(Object obj);
+
+    /**
+     * A hash code for this date-time.
+     *
+     * @return a suitable hash code
+     */
+    @Override
+    int hashCode();
+
+    //-----------------------------------------------------------------------
+    /**
+     * Outputs this date-time as a {@code String}.
+     * <p>
+     * The output will include the full local date-time and the chronology ID.
+     *
+     * @return a string representation of this date-time, not null
+     */
+    @Override
+    String toString();
+
+    /**
+     * Outputs this date-time as a {@code String} using the formatter.
+     * <p>
+     * The default implementation must behave as follows:
+     * <pre>
+     *  return formatter.format(this);
+     * </pre>
+     *
+     * @param formatter  the formatter to use, not null
+     * @return the formatted date-time string, not null
+     * @throws DateTimeException if an error occurs during printing
+     */
+    public default String toString(DateTimeFormatter formatter) {
+        Objects.requireNonNull(formatter, "formatter");
+        return formatter.format(this);
+    }
+}