changeset 20794:ec823009c5f7

8025719: Change Chronology to an interface Summary: Split Chronology and add AbstractChronology Reviewed-by: darcy Contributed-by: scolebourne@joda.org
author scolebourne
date Tue, 09 Jul 2013 21:35:04 +0100
parents 5acd4b8d70a1
children 8ec9e5b79828
files jdk/src/share/classes/java/time/chrono/AbstractChronology.java jdk/src/share/classes/java/time/chrono/ChronoLocalDate.java jdk/src/share/classes/java/time/chrono/ChronoLocalDateTime.java jdk/src/share/classes/java/time/chrono/ChronoZonedDateTime.java jdk/src/share/classes/java/time/chrono/Chronology.java jdk/src/share/classes/java/time/chrono/HijrahChronology.java jdk/src/share/classes/java/time/chrono/IsoChronology.java jdk/src/share/classes/java/time/chrono/JapaneseChronology.java jdk/src/share/classes/java/time/chrono/MinguoChronology.java jdk/src/share/classes/java/time/chrono/Ser.java jdk/src/share/classes/java/time/chrono/ThaiBuddhistChronology.java jdk/test/java/time/tck/java/time/chrono/CopticChronology.java
diffstat 12 files changed, 864 insertions(+), 663 deletions(-) [+]
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/time/chrono/AbstractChronology.java	Tue Jul 09 21:35:04 2013 +0100
@@ -0,0 +1,783 @@
+/*
+ * 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) 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.ALIGNED_DAY_OF_WEEK_IN_MONTH;
+import static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR;
+import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_MONTH;
+import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_YEAR;
+import static java.time.temporal.ChronoField.DAY_OF_MONTH;
+import static java.time.temporal.ChronoField.DAY_OF_WEEK;
+import static java.time.temporal.ChronoField.DAY_OF_YEAR;
+import static java.time.temporal.ChronoField.EPOCH_DAY;
+import static java.time.temporal.ChronoField.ERA;
+import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
+import static java.time.temporal.ChronoField.PROLEPTIC_MONTH;
+import static java.time.temporal.ChronoField.YEAR;
+import static java.time.temporal.ChronoField.YEAR_OF_ERA;
+import static java.time.temporal.ChronoUnit.DAYS;
+import static java.time.temporal.ChronoUnit.MONTHS;
+import static java.time.temporal.ChronoUnit.WEEKS;
+import static java.time.temporal.TemporalAdjuster.nextOrSame;
+
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+import java.io.InvalidObjectException;
+import java.io.ObjectStreamException;
+import java.io.Serializable;
+import java.time.DateTimeException;
+import java.time.DayOfWeek;
+import java.time.format.ResolverStyle;
+import java.time.temporal.ChronoField;
+import java.time.temporal.TemporalAdjuster;
+import java.time.temporal.TemporalField;
+import java.time.temporal.ValueRange;
+import java.util.Comparator;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Objects;
+import java.util.ServiceLoader;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+import sun.util.logging.PlatformLogger;
+
+/**
+ * An abstract implementation of a calendar system, used to organize and identify dates.
+ * <p>
+ * The main date and time API is built on the ISO calendar system.
+ * The chronology operates behind the scenes to represent the general concept of a calendar system.
+ * <p>
+ * See {@link Chronology} for more details.
+ *
+ * @implSpec
+ * This class is separated from the {@code Chronology} interface so that the static methods
+ * are not inherited. While {@code Chronology} can be implemented directly, it is strongly
+ * recommended to extend this abstract class instead.
+ * <p>
+ * This class 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.
+ *
+ * @since 1.8
+ */
+public abstract class AbstractChronology implements Chronology {
+
+    /**
+     * ChronoLocalDate order constant.
+     */
+    static final Comparator<ChronoLocalDate> DATE_ORDER =
+        (Comparator<ChronoLocalDate> & Serializable) (date1, date2) -> {
+            return Long.compare(date1.toEpochDay(), date2.toEpochDay());
+        };
+    /**
+     * ChronoLocalDateTime order constant.
+     */
+    static final Comparator<ChronoLocalDateTime<? extends ChronoLocalDate>> DATE_TIME_ORDER =
+        (Comparator<ChronoLocalDateTime<? extends ChronoLocalDate>> & Serializable) (dateTime1, 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;
+        };
+    /**
+     * ChronoZonedDateTime order constant.
+     */
+    static final Comparator<ChronoZonedDateTime<?>> INSTANT_ORDER =
+            (Comparator<ChronoZonedDateTime<?>> & Serializable) (dateTime1, dateTime2) -> {
+                int cmp = Long.compare(dateTime1.toEpochSecond(), dateTime2.toEpochSecond());
+                if (cmp == 0) {
+                    cmp = Long.compare(dateTime1.toLocalTime().getNano(), dateTime2.toLocalTime().getNano());
+                }
+                return cmp;
+            };
+
+    /**
+     * Map of available calendars by ID.
+     */
+    private static final ConcurrentHashMap<String, Chronology> CHRONOS_BY_ID = new ConcurrentHashMap<>();
+    /**
+     * Map of available calendars by calendar type.
+     */
+    private static final ConcurrentHashMap<String, Chronology> CHRONOS_BY_TYPE = new ConcurrentHashMap<>();
+
+    /**
+     * Register a Chronology by its ID and type for lookup by {@link #of(String)}.
+     * Chronologies must not be registered until they are completely constructed.
+     * Specifically, not in the constructor of Chronology.
+     *
+     * @param chrono the chronology to register; not null
+     * @return the already registered Chronology if any, may be null
+     */
+    static Chronology registerChrono(Chronology chrono) {
+        return registerChrono(chrono, chrono.getId());
+    }
+
+    /**
+     * Register a Chronology by ID and type for lookup by {@link #of(String)}.
+     * Chronos must not be registered until they are completely constructed.
+     * Specifically, not in the constructor of Chronology.
+     *
+     * @param chrono the chronology to register; not null
+     * @param id the ID to register the chronology; not null
+     * @return the already registered Chronology if any, may be null
+     */
+    static Chronology registerChrono(Chronology chrono, String id) {
+        Chronology prev = CHRONOS_BY_ID.putIfAbsent(id, chrono);
+        if (prev == null) {
+            String type = chrono.getCalendarType();
+            if (type != null) {
+                CHRONOS_BY_TYPE.putIfAbsent(type, chrono);
+            }
+        }
+        return prev;
+    }
+
+    /**
+     * Initialization of the maps from id and type to Chronology.
+     * The ServiceLoader is used to find and register any implementations
+     * of {@link java.time.chrono.AbstractChronology} found in the bootclass loader.
+     * The built-in chronologies are registered explicitly.
+     * Calendars configured via the Thread's context classloader are local
+     * to that thread and are ignored.
+     * <p>
+     * The initialization is done only once using the registration
+     * of the IsoChronology as the test and the final step.
+     * Multiple threads may perform the initialization concurrently.
+     * Only the first registration of each Chronology is retained by the
+     * ConcurrentHashMap.
+     * @return true if the cache was initialized
+     */
+    private static boolean initCache() {
+        if (CHRONOS_BY_ID.get("ISO") == null) {
+            // Initialization is incomplete
+
+            // Register built-in Chronologies
+            registerChrono(HijrahChronology.INSTANCE);
+            registerChrono(JapaneseChronology.INSTANCE);
+            registerChrono(MinguoChronology.INSTANCE);
+            registerChrono(ThaiBuddhistChronology.INSTANCE);
+
+            // Register Chronologies from the ServiceLoader
+            @SuppressWarnings("rawtypes")
+            ServiceLoader<AbstractChronology> loader =  ServiceLoader.load(AbstractChronology.class, null);
+            for (AbstractChronology chrono : loader) {
+                String id = chrono.getId();
+                if (id.equals("ISO") || registerChrono(chrono) != null) {
+                    // Log the attempt to replace an existing Chronology
+                    PlatformLogger logger = PlatformLogger.getLogger("java.time.chrono");
+                    logger.warning("Ignoring duplicate Chronology, from ServiceLoader configuration "  + id);
+                }
+            }
+
+            // finally, register IsoChronology to mark initialization is complete
+            registerChrono(IsoChronology.INSTANCE);
+            return true;
+        }
+        return false;
+    }
+
+    //-----------------------------------------------------------------------
+    /**
+     * Obtains an instance of {@code Chronology} from a locale.
+     * <p>
+     * See {@link Chronology#ofLocale(Locale)}.
+     *
+     * @param locale  the locale to use to obtain the calendar system, not null
+     * @return the calendar system associated with the locale, not null
+     * @throws java.time.DateTimeException if the locale-specified calendar cannot be found
+     */
+    static Chronology ofLocale(Locale locale) {
+        Objects.requireNonNull(locale, "locale");
+        String type = locale.getUnicodeLocaleType("ca");
+        if (type == null || "iso".equals(type) || "iso8601".equals(type)) {
+            return IsoChronology.INSTANCE;
+        }
+        // Not pre-defined; lookup by the type
+        do {
+            Chronology chrono = CHRONOS_BY_TYPE.get(type);
+            if (chrono != null) {
+                return chrono;
+            }
+            // If not found, do the initialization (once) and repeat the lookup
+        } while (initCache());
+
+        // Look for a Chronology using ServiceLoader of the Thread's ContextClassLoader
+        // Application provided Chronologies must not be cached
+        @SuppressWarnings("rawtypes")
+        ServiceLoader<Chronology> loader = ServiceLoader.load(Chronology.class);
+        for (Chronology chrono : loader) {
+            if (type.equals(chrono.getCalendarType())) {
+                return chrono;
+            }
+        }
+        throw new DateTimeException("Unknown calendar system: " + type);
+    }
+
+    //-----------------------------------------------------------------------
+    /**
+     * Obtains an instance of {@code Chronology} from a chronology ID or
+     * calendar system type.
+     * <p>
+     * See {@link Chronology#of(String)}.
+     *
+     * @param id  the chronology ID or calendar system type, not null
+     * @return the chronology with the identifier requested, not null
+     * @throws java.time.DateTimeException if the chronology cannot be found
+     */
+    static Chronology of(String id) {
+        Objects.requireNonNull(id, "id");
+        do {
+            Chronology chrono = of0(id);
+            if (chrono != null) {
+                return chrono;
+            }
+            // If not found, do the initialization (once) and repeat the lookup
+        } while (initCache());
+
+        // Look for a Chronology using ServiceLoader of the Thread's ContextClassLoader
+        // Application provided Chronologies must not be cached
+        @SuppressWarnings("rawtypes")
+        ServiceLoader<Chronology> loader = ServiceLoader.load(Chronology.class);
+        for (Chronology chrono : loader) {
+            if (id.equals(chrono.getId()) || id.equals(chrono.getCalendarType())) {
+                return chrono;
+            }
+        }
+        throw new DateTimeException("Unknown chronology: " + id);
+    }
+
+    /**
+     * Obtains an instance of {@code Chronology} from a chronology ID or
+     * calendar system type.
+     *
+     * @param id  the chronology ID or calendar system type, not null
+     * @return the chronology with the identifier requested, or {@code null} if not found
+     */
+    private static Chronology of0(String id) {
+        Chronology chrono = CHRONOS_BY_ID.get(id);
+        if (chrono == null) {
+            chrono = CHRONOS_BY_TYPE.get(id);
+        }
+        return chrono;
+    }
+
+    /**
+     * Returns the available chronologies.
+     * <p>
+     * Each returned {@code Chronology} is available for use in the system.
+     * The set of chronologies includes the system chronologies and
+     * any chronologies provided by the application via ServiceLoader
+     * configuration.
+     *
+     * @return the independent, modifiable set of the available chronology IDs, not null
+     */
+    static Set<Chronology> getAvailableChronologies() {
+        initCache();       // force initialization
+        HashSet<Chronology> chronos = new HashSet<>(CHRONOS_BY_ID.values());
+
+        /// Add in Chronologies from the ServiceLoader configuration
+        @SuppressWarnings("rawtypes")
+        ServiceLoader<Chronology> loader = ServiceLoader.load(Chronology.class);
+        for (Chronology chrono : loader) {
+            chronos.add(chrono);
+        }
+        return chronos;
+    }
+
+    //-----------------------------------------------------------------------
+    /**
+     * Creates an instance.
+     */
+    protected AbstractChronology() {
+    }
+
+    //-----------------------------------------------------------------------
+    /**
+     * Resolves parsed {@code ChronoField} values into a date during parsing.
+     * <p>
+     * Most {@code TemporalField} implementations are resolved using the
+     * resolve method on the field. By contrast, the {@code ChronoField} class
+     * defines fields that only have meaning relative to the chronology.
+     * As such, {@code ChronoField} date fields are resolved here in the
+     * context of a specific chronology.
+     * <p>
+     * {@code ChronoField} instances are resolved by this method, which may
+     * be overridden in subclasses.
+     * <ul>
+     * <li>{@code EPOCH_DAY} - If present, this is converted to a date and
+     *  all other date fields are then cross-checked against the date.
+     * <li>{@code PROLEPTIC_MONTH} - If present, then it is split into the
+     *  {@code YEAR} and {@code MONTH_OF_YEAR}. If the mode is strict or smart
+     *  then the field is validated.
+     * <li>{@code YEAR_OF_ERA} and {@code ERA} - If both are present, then they
+     *  are combined to form a {@code YEAR}. In lenient mode, the {@code YEAR_OF_ERA}
+     *  range is not validated, in smart and strict mode it is. The {@code ERA} is
+     *  validated for range in all three modes. If only the {@code YEAR_OF_ERA} is
+     *  present, and the mode is smart or lenient, then the last available era
+     *  is assumed. In strict mode, no era is assumed and the {@code YEAR_OF_ERA} is
+     *  left untouched. If only the {@code ERA} is present, then it is left untouched.
+     * <li>{@code YEAR}, {@code MONTH_OF_YEAR} and {@code DAY_OF_MONTH} -
+     *  If all three are present, then they are combined to form a date.
+     *  In all three modes, the {@code YEAR} is validated.
+     *  If the mode is smart or strict, then the month and day are validated.
+     *  If the mode is lenient, then the date is combined in a manner equivalent to
+     *  creating a date on the first day of the first month in the requested year,
+     *  then adding the difference in months, then the difference in days.
+     *  If the mode is smart, and the day-of-month is greater than the maximum for
+     *  the year-month, then the day-of-month is adjusted to the last day-of-month.
+     *  If the mode is strict, then the three fields must form a valid date.
+     * <li>{@code YEAR} and {@code DAY_OF_YEAR} -
+     *  If both are present, then they are combined to form a date.
+     *  In all three modes, the {@code YEAR} is validated.
+     *  If the mode is lenient, then the date is combined in a manner equivalent to
+     *  creating a date on the first day of the requested year, then adding
+     *  the difference in days.
+     *  If the mode is smart or strict, then the two fields must form a valid date.
+     * <li>{@code YEAR}, {@code MONTH_OF_YEAR}, {@code ALIGNED_WEEK_OF_MONTH} and
+     *  {@code ALIGNED_DAY_OF_WEEK_IN_MONTH} -
+     *  If all four are present, then they are combined to form a date.
+     *  In all three modes, the {@code YEAR} is validated.
+     *  If the mode is lenient, then the date is combined in a manner equivalent to
+     *  creating a date on the first day of the first month in the requested year, then adding
+     *  the difference in months, then the difference in weeks, then in days.
+     *  If the mode is smart or strict, then the all four fields are validated to
+     *  their outer ranges. The date is then combined in a manner equivalent to
+     *  creating a date on the first day of the requested year and month, then adding
+     *  the amount in weeks and days to reach their values. If the mode is strict,
+     *  the date is additionally validated to check that the day and week adjustment
+     *  did not change the month.
+     * <li>{@code YEAR}, {@code MONTH_OF_YEAR}, {@code ALIGNED_WEEK_OF_MONTH} and
+     *  {@code DAY_OF_WEEK} - If all four are present, then they are combined to
+     *  form a date. The approach is the same as described above for
+     *  years, months and weeks in {@code ALIGNED_DAY_OF_WEEK_IN_MONTH}.
+     *  The day-of-week is adjusted as the next or same matching day-of-week once
+     *  the years, months and weeks have been handled.
+     * <li>{@code YEAR}, {@code ALIGNED_WEEK_OF_YEAR} and {@code ALIGNED_DAY_OF_WEEK_IN_YEAR} -
+     *  If all three are present, then they are combined to form a date.
+     *  In all three modes, the {@code YEAR} is validated.
+     *  If the mode is lenient, then the date is combined in a manner equivalent to
+     *  creating a date on the first day of the requested year, then adding
+     *  the difference in weeks, then in days.
+     *  If the mode is smart or strict, then the all three fields are validated to
+     *  their outer ranges. The date is then combined in a manner equivalent to
+     *  creating a date on the first day of the requested year, then adding
+     *  the amount in weeks and days to reach their values. If the mode is strict,
+     *  the date is additionally validated to check that the day and week adjustment
+     *  did not change the year.
+     * <li>{@code YEAR}, {@code ALIGNED_WEEK_OF_YEAR} and {@code DAY_OF_WEEK} -
+     *  If all three are present, then they are combined to form a date.
+     *  The approach is the same as described above for years and weeks in
+     *  {@code ALIGNED_DAY_OF_WEEK_IN_YEAR}. The day-of-week is adjusted as the
+     *  next or same matching day-of-week once the years and weeks have been handled.
+     * </ul>
+     * <p>
+     * The default implementation is suitable for most calendar systems.
+     * If {@link java.time.temporal.ChronoField#YEAR_OF_ERA} is found without an {@link java.time.temporal.ChronoField#ERA}
+     * then the last era in {@link #eras()} is used.
+     * The implementation assumes a 7 day week, that the first day-of-month
+     * has the value 1, that first day-of-year has the value 1, and that the
+     * first of the month and year always exists.
+     *
+     * @param fieldValues  the map of fields to values, which can be updated, not null
+     * @param resolverStyle  the requested type of resolve, not null
+     * @return the resolved date, null if insufficient information to create a date
+     * @throws java.time.DateTimeException if the date cannot be resolved, typically
+     *  because of a conflict in the input data
+     */
+    @Override
+    public ChronoLocalDate resolveDate(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
+        // check epoch-day before inventing era
+        if (fieldValues.containsKey(EPOCH_DAY)) {
+            return dateEpochDay(fieldValues.remove(EPOCH_DAY));
+        }
+
+        // fix proleptic month before inventing era
+        resolveProlepticMonth(fieldValues, resolverStyle);
+
+        // invent era if necessary to resolve year-of-era
+        ChronoLocalDate resolved = resolveYearOfEra(fieldValues, resolverStyle);
+        if (resolved != null) {
+            return resolved;
+        }
+
+        // build date
+        if (fieldValues.containsKey(YEAR)) {
+            if (fieldValues.containsKey(MONTH_OF_YEAR)) {
+                if (fieldValues.containsKey(DAY_OF_MONTH)) {
+                    return resolveYMD(fieldValues, resolverStyle);
+                }
+                if (fieldValues.containsKey(ALIGNED_WEEK_OF_MONTH)) {
+                    if (fieldValues.containsKey(ALIGNED_DAY_OF_WEEK_IN_MONTH)) {
+                        return resolveYMAA(fieldValues, resolverStyle);
+                    }
+                    if (fieldValues.containsKey(DAY_OF_WEEK)) {
+                        return resolveYMAD(fieldValues, resolverStyle);
+                    }
+                }
+            }
+            if (fieldValues.containsKey(DAY_OF_YEAR)) {
+                return resolveYD(fieldValues, resolverStyle);
+            }
+            if (fieldValues.containsKey(ALIGNED_WEEK_OF_YEAR)) {
+                if (fieldValues.containsKey(ALIGNED_DAY_OF_WEEK_IN_YEAR)) {
+                    return resolveYAA(fieldValues, resolverStyle);
+                }
+                if (fieldValues.containsKey(DAY_OF_WEEK)) {
+                    return resolveYAD(fieldValues, resolverStyle);
+                }
+            }
+        }
+        return null;
+    }
+
+    void resolveProlepticMonth(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
+        Long pMonth = fieldValues.remove(PROLEPTIC_MONTH);
+        if (pMonth != null) {
+            if (resolverStyle != ResolverStyle.LENIENT) {
+                PROLEPTIC_MONTH.checkValidValue(pMonth);
+            }
+            // first day-of-month is likely to be safest for setting proleptic-month
+            // cannot add to year zero, as not all chronologies have a year zero
+            ChronoLocalDate chronoDate = dateNow()
+                    .with(DAY_OF_MONTH, 1).with(PROLEPTIC_MONTH, pMonth);
+            addFieldValue(fieldValues, MONTH_OF_YEAR, chronoDate.get(MONTH_OF_YEAR));
+            addFieldValue(fieldValues, YEAR, chronoDate.get(YEAR));
+        }
+    }
+
+    ChronoLocalDate resolveYearOfEra(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
+        Long yoeLong = fieldValues.remove(YEAR_OF_ERA);
+        if (yoeLong != null) {
+            Long eraLong = fieldValues.remove(ERA);
+            int yoe;
+            if (resolverStyle != ResolverStyle.LENIENT) {
+                yoe = range(YEAR_OF_ERA).checkValidIntValue(yoeLong, YEAR_OF_ERA);
+            } else {
+                yoe = Math.toIntExact(yoeLong);
+            }
+            if (eraLong != null) {
+                Era eraObj = eraOf(range(ERA).checkValidIntValue(eraLong, ERA));
+                addFieldValue(fieldValues, YEAR, prolepticYear(eraObj, yoe));
+            } else {
+                if (fieldValues.containsKey(YEAR)) {
+                    int year = range(YEAR).checkValidIntValue(fieldValues.get(YEAR), YEAR);
+                    ChronoLocalDate chronoDate = dateYearDay(year, 1);
+                    addFieldValue(fieldValues, YEAR, prolepticYear(chronoDate.getEra(), yoe));
+                } else if (resolverStyle == ResolverStyle.STRICT) {
+                    // do not invent era if strict
+                    // reinstate the field removed earlier, no cross-check issues
+                    fieldValues.put(YEAR_OF_ERA, yoeLong);
+                } else {
+                    List<Era> eras = eras();
+                    if (eras.isEmpty()) {
+                        addFieldValue(fieldValues, YEAR, yoe);
+                    } else {
+                        Era eraObj = eras.get(eras.size() - 1);
+                        addFieldValue(fieldValues, YEAR, prolepticYear(eraObj, yoe));
+                    }
+                }
+            }
+        } else if (fieldValues.containsKey(ERA)) {
+            range(ERA).checkValidValue(fieldValues.get(ERA), ERA);  // always validated
+        }
+        return null;
+    }
+
+    ChronoLocalDate resolveYMD(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
+        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
+        if (resolverStyle == ResolverStyle.LENIENT) {
+            long months = Math.subtractExact(fieldValues.remove(MONTH_OF_YEAR), 1);
+            long days = Math.subtractExact(fieldValues.remove(DAY_OF_MONTH), 1);
+            return date(y, 1, 1).plus(months, MONTHS).plus(days, DAYS);
+        }
+        int moy = range(MONTH_OF_YEAR).checkValidIntValue(fieldValues.remove(MONTH_OF_YEAR), MONTH_OF_YEAR);
+        ValueRange domRange = range(DAY_OF_MONTH);
+        int dom = domRange.checkValidIntValue(fieldValues.remove(DAY_OF_MONTH), DAY_OF_MONTH);
+        if (resolverStyle == ResolverStyle.SMART) {  // previous valid
+            try {
+                return date(y, moy, dom);
+            } catch (DateTimeException ex) {
+                return date(y, moy, 1).with(TemporalAdjuster.lastDayOfMonth());
+            }
+        }
+        return date(y, moy, dom);
+    }
+
+    ChronoLocalDate resolveYD(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
+        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
+        if (resolverStyle == ResolverStyle.LENIENT) {
+            long days = Math.subtractExact(fieldValues.remove(DAY_OF_YEAR), 1);
+            return dateYearDay(y, 1).plus(days, DAYS);
+        }
+        int doy = range(DAY_OF_YEAR).checkValidIntValue(fieldValues.remove(DAY_OF_YEAR), DAY_OF_YEAR);
+        return dateYearDay(y, doy);  // smart is same as strict
+    }
+
+    ChronoLocalDate resolveYMAA(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
+        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
+        if (resolverStyle == ResolverStyle.LENIENT) {
+            long months = Math.subtractExact(fieldValues.remove(MONTH_OF_YEAR), 1);
+            long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), 1);
+            long days = Math.subtractExact(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_MONTH), 1);
+            return date(y, 1, 1).plus(months, MONTHS).plus(weeks, WEEKS).plus(days, DAYS);
+        }
+        int moy = range(MONTH_OF_YEAR).checkValidIntValue(fieldValues.remove(MONTH_OF_YEAR), MONTH_OF_YEAR);
+        int aw = range(ALIGNED_WEEK_OF_MONTH).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), ALIGNED_WEEK_OF_MONTH);
+        int ad = range(ALIGNED_DAY_OF_WEEK_IN_MONTH).checkValidIntValue(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_MONTH), ALIGNED_DAY_OF_WEEK_IN_MONTH);
+        ChronoLocalDate date = date(y, moy, 1).plus((aw - 1) * 7 + (ad - 1), DAYS);
+        if (resolverStyle == ResolverStyle.STRICT && date.get(MONTH_OF_YEAR) != moy) {
+            throw new DateTimeException("Strict mode rejected resolved date as it is in a different month");
+        }
+        return date;
+    }
+
+    ChronoLocalDate resolveYMAD(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
+        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
+        if (resolverStyle == ResolverStyle.LENIENT) {
+            long months = Math.subtractExact(fieldValues.remove(MONTH_OF_YEAR), 1);
+            long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), 1);
+            long dow = Math.subtractExact(fieldValues.remove(DAY_OF_WEEK), 1);
+            return resolveAligned(date(y, 1, 1), months, weeks, dow);
+        }
+        int moy = range(MONTH_OF_YEAR).checkValidIntValue(fieldValues.remove(MONTH_OF_YEAR), MONTH_OF_YEAR);
+        int aw = range(ALIGNED_WEEK_OF_MONTH).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), ALIGNED_WEEK_OF_MONTH);
+        int dow = range(DAY_OF_WEEK).checkValidIntValue(fieldValues.remove(DAY_OF_WEEK), DAY_OF_WEEK);
+        ChronoLocalDate date = date(y, moy, 1).plus((aw - 1) * 7, DAYS).with(nextOrSame(DayOfWeek.of(dow)));
+        if (resolverStyle == ResolverStyle.STRICT && date.get(MONTH_OF_YEAR) != moy) {
+            throw new DateTimeException("Strict mode rejected resolved date as it is in a different month");
+        }
+        return date;
+    }
+
+    ChronoLocalDate resolveYAA(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
+        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
+        if (resolverStyle == ResolverStyle.LENIENT) {
+            long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), 1);
+            long days = Math.subtractExact(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_YEAR), 1);
+            return dateYearDay(y, 1).plus(weeks, WEEKS).plus(days, DAYS);
+        }
+        int aw = range(ALIGNED_WEEK_OF_YEAR).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), ALIGNED_WEEK_OF_YEAR);
+        int ad = range(ALIGNED_DAY_OF_WEEK_IN_YEAR).checkValidIntValue(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_YEAR), ALIGNED_DAY_OF_WEEK_IN_YEAR);
+        ChronoLocalDate date = dateYearDay(y, 1).plus((aw - 1) * 7 + (ad - 1), DAYS);
+        if (resolverStyle == ResolverStyle.STRICT && date.get(YEAR) != y) {
+            throw new DateTimeException("Strict mode rejected resolved date as it is in a different year");
+        }
+        return date;
+    }
+
+    ChronoLocalDate resolveYAD(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
+        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
+        if (resolverStyle == ResolverStyle.LENIENT) {
+            long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), 1);
+            long dow = Math.subtractExact(fieldValues.remove(DAY_OF_WEEK), 1);
+            return resolveAligned(dateYearDay(y, 1), 0, weeks, dow);
+        }
+        int aw = range(ALIGNED_WEEK_OF_YEAR).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), ALIGNED_WEEK_OF_YEAR);
+        int dow = range(DAY_OF_WEEK).checkValidIntValue(fieldValues.remove(DAY_OF_WEEK), DAY_OF_WEEK);
+        ChronoLocalDate date = dateYearDay(y, 1).plus((aw - 1) * 7, DAYS).with(nextOrSame(DayOfWeek.of(dow)));
+        if (resolverStyle == ResolverStyle.STRICT && date.get(YEAR) != y) {
+            throw new DateTimeException("Strict mode rejected resolved date as it is in a different year");
+        }
+        return date;
+    }
+
+    ChronoLocalDate resolveAligned(ChronoLocalDate base, long months, long weeks, long dow) {
+        ChronoLocalDate date = base.plus(months, MONTHS).plus(weeks, WEEKS);
+        if (dow > 7) {
+            date = date.plus((dow - 1) / 7, WEEKS);
+            dow = ((dow - 1) % 7) + 1;
+        } else if (dow < 1) {
+            date = date.plus(Math.subtractExact(dow,  7) / 7, WEEKS);
+            dow = ((dow + 6) % 7) + 1;
+        }
+        return date.with(nextOrSame(DayOfWeek.of((int) dow)));
+    }
+
+    /**
+     * Adds a field-value pair to the map, checking for conflicts.
+     * <p>
+     * If the field is not already present, then the field-value pair is added to the map.
+     * If the field is already present and it has the same value as that specified, no action occurs.
+     * If the field is already present and it has a different value to that specified, then
+     * an exception is thrown.
+     *
+     * @param field  the field to add, not null
+     * @param value  the value to add, not null
+     * @throws java.time.DateTimeException if the field is already present with a different value
+     */
+    void addFieldValue(Map<TemporalField, Long> fieldValues, ChronoField field, long value) {
+        Long old = fieldValues.get(field);  // check first for better error message
+        if (old != null && old.longValue() != value) {
+            throw new DateTimeException("Conflict found: " + field + " " + old + " differs from " + field + " " + value);
+        }
+        fieldValues.put(field, value);
+    }
+
+    //-----------------------------------------------------------------------
+    /**
+     * Compares this chronology to another chronology.
+     * <p>
+     * The comparison order first by the chronology ID string, then by any
+     * additional information specific to the subclass.
+     * It is "consistent with equals", as defined by {@link Comparable}.
+     *
+     * @implSpec
+     * This implementation compares the chronology ID.
+     * Subclasses must compare any additional state that they store.
+     *
+     * @param other  the other chronology to compare to, not null
+     * @return the comparator value, negative if less, positive if greater
+     */
+    @Override
+    public int compareTo(Chronology other) {
+        return getId().compareTo(other.getId());
+    }
+
+    /**
+     * Checks if this chronology is equal to another chronology.
+     * <p>
+     * The comparison is based on the entire state of the object.
+     *
+     * @implSpec
+     * This implementation checks the type and calls
+     * {@link #compareTo(java.time.chrono.Chronology)}.
+     *
+     * @param obj  the object to check, null returns false
+     * @return true if this is equal to the other chronology
+     */
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+           return true;
+        }
+        if (obj instanceof AbstractChronology) {
+            return compareTo((AbstractChronology) obj) == 0;
+        }
+        return false;
+    }
+
+    /**
+     * A hash code for this chronology.
+     * <p>
+     * The hash code should be based on the entire state of the object.
+     *
+     * @implSpec
+     * This implementation is based on the chronology ID and class.
+     * Subclasses should add any additional state that they store.
+     *
+     * @return a suitable hash code
+     */
+    @Override
+    public int hashCode() {
+        return getClass().hashCode() ^ getId().hashCode();
+    }
+
+    //-----------------------------------------------------------------------
+    /**
+     * Outputs this chronology as a {@code String}, using the chronology ID.
+     *
+     * @return a string representation of this chronology, not null
+     */
+    @Override
+    public String toString() {
+        return getId();
+    }
+
+    //-----------------------------------------------------------------------
+    /**
+     * Writes the Chronology using a
+     * <a href="../../../serialized-form.html#java.time.chrono.Ser">dedicated serialized form</a>.
+     * <pre>
+     *  out.writeByte(1);  // identifies this as a Chronology
+     *  out.writeUTF(getId());
+     * </pre>
+     *
+     * @return the instance of {@code Ser}, not null
+     */
+    Object writeReplace() {
+        return new Ser(Ser.CHRONO_TYPE, this);
+    }
+
+    /**
+     * Defend against malicious streams.
+     * @return never
+     * @throws java.io.InvalidObjectException always
+     */
+    private Object readResolve() throws ObjectStreamException {
+        throw new InvalidObjectException("Deserialization via serialization delegate");
+    }
+
+    void writeExternal(DataOutput out) throws IOException {
+        out.writeUTF(getId());
+    }
+
+    static Chronology readExternal(DataInput in) throws IOException {
+        String id = in.readUTF();
+        return Chronology.of(id);
+    }
+
+}
--- a/jdk/src/share/classes/java/time/chrono/ChronoLocalDate.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/src/share/classes/java/time/chrono/ChronoLocalDate.java	Tue Jul 09 21:35:04 2013 +0100
@@ -262,7 +262,7 @@
      * @see #isEqual
      */
     static Comparator<ChronoLocalDate> timeLineOrder() {
-        return Chronology.DATE_ORDER;
+        return AbstractChronology.DATE_ORDER;
     }
 
     //-----------------------------------------------------------------------
--- a/jdk/src/share/classes/java/time/chrono/ChronoLocalDateTime.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/src/share/classes/java/time/chrono/ChronoLocalDateTime.java	Tue Jul 09 21:35:04 2013 +0100
@@ -136,7 +136,7 @@
      * @see #isEqual
      */
     static Comparator<ChronoLocalDateTime<?>> timeLineOrder() {
-        return Chronology.DATE_TIME_ORDER;
+        return AbstractChronology.DATE_TIME_ORDER;
     }
 
     //-----------------------------------------------------------------------
--- a/jdk/src/share/classes/java/time/chrono/ChronoZonedDateTime.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/src/share/classes/java/time/chrono/ChronoZonedDateTime.java	Tue Jul 09 21:35:04 2013 +0100
@@ -137,7 +137,7 @@
      * @see #isEqual
      */
     static Comparator<ChronoZonedDateTime<?>> timeLineOrder() {
-        return Chronology.INSTANT_ORDER;
+        return AbstractChronology.INSTANT_ORDER;
     }
 
     //-----------------------------------------------------------------------
--- a/jdk/src/share/classes/java/time/chrono/Chronology.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/src/share/classes/java/time/chrono/Chronology.java	Tue Jul 09 21:35:04 2013 +0100
@@ -61,33 +61,8 @@
  */
 package java.time.chrono;
 
-import static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH;
-import static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR;
-import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_MONTH;
-import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_YEAR;
-import static java.time.temporal.ChronoField.DAY_OF_MONTH;
-import static java.time.temporal.ChronoField.DAY_OF_WEEK;
-import static java.time.temporal.ChronoField.DAY_OF_YEAR;
-import static java.time.temporal.ChronoField.EPOCH_DAY;
-import static java.time.temporal.ChronoField.ERA;
-import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
-import static java.time.temporal.ChronoField.PROLEPTIC_MONTH;
-import static java.time.temporal.ChronoField.YEAR;
-import static java.time.temporal.ChronoField.YEAR_OF_ERA;
-import static java.time.temporal.ChronoUnit.DAYS;
-import static java.time.temporal.ChronoUnit.MONTHS;
-import static java.time.temporal.ChronoUnit.WEEKS;
-import static java.time.temporal.TemporalAdjuster.nextOrSame;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-import java.io.InvalidObjectException;
-import java.io.ObjectStreamException;
-import java.io.Serializable;
 import java.time.Clock;
 import java.time.DateTimeException;
-import java.time.DayOfWeek;
 import java.time.Instant;
 import java.time.LocalDate;
 import java.time.LocalTime;
@@ -97,28 +72,21 @@
 import java.time.format.TextStyle;
 import java.time.temporal.ChronoField;
 import java.time.temporal.TemporalAccessor;
-import java.time.temporal.TemporalAdjuster;
 import java.time.temporal.TemporalField;
 import java.time.temporal.TemporalQuery;
 import java.time.temporal.UnsupportedTemporalTypeException;
 import java.time.temporal.ValueRange;
-import java.util.Comparator;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
-import java.util.ServiceLoader;
 import java.util.Set;
-import java.util.concurrent.ConcurrentHashMap;
-
-import sun.util.logging.PlatformLogger;
 
 /**
  * A calendar system, used to organize and identify dates.
  * <p>
  * The main date and time API is built on the ISO calendar system.
- * This class operates behind the scenes to represent the general concept of a calendar system.
+ * The chronology operates behind the scenes to represent the general concept of a calendar system.
  * For example, the Japanese, Minguo, Thai Buddhist and others.
  * <p>
  * Most other calendar systems also operate on the shared concepts of year, month and day,
@@ -179,131 +147,15 @@
  * CLDR type and, if applicable, the CLDR variant,
  *
  * @implSpec
- * This class must be implemented with care to ensure other classes operate correctly.
+ * 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.
  *
  * @since 1.8
  */
-public abstract class Chronology implements Comparable<Chronology> {
+public interface Chronology extends Comparable<Chronology> {
 
     /**
-     * ChronoLocalDate order constant.
-     */
-    static final Comparator<ChronoLocalDate> DATE_ORDER =
-        (Comparator<ChronoLocalDate> & Serializable) (date1, date2) -> {
-            return Long.compare(date1.toEpochDay(), date2.toEpochDay());
-        };
-    /**
-     * ChronoLocalDateTime order constant.
-     */
-    static final Comparator<ChronoLocalDateTime<?>> DATE_TIME_ORDER =
-        (Comparator<ChronoLocalDateTime<?>> & Serializable) (dateTime1, 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;
-        };
-    /**
-     * ChronoZonedDateTime order constant.
-     */
-    static final Comparator<ChronoZonedDateTime<?>> INSTANT_ORDER =
-            (Comparator<ChronoZonedDateTime<?>> & Serializable) (dateTime1, dateTime2) -> {
-                int cmp = Long.compare(dateTime1.toEpochSecond(), dateTime2.toEpochSecond());
-                if (cmp == 0) {
-                    cmp = Long.compare(dateTime1.toLocalTime().getNano(), dateTime2.toLocalTime().getNano());
-                }
-                return cmp;
-            };
-
-    /**
-     * Map of available calendars by ID.
-     */
-    private static final ConcurrentHashMap<String, Chronology> CHRONOS_BY_ID = new ConcurrentHashMap<>();
-    /**
-     * Map of available calendars by calendar type.
-     */
-    private static final ConcurrentHashMap<String, Chronology> CHRONOS_BY_TYPE = new ConcurrentHashMap<>();
-
-    /**
-     * Register a Chronology by its ID and type for lookup by {@link #of(java.lang.String)}.
-     * Chronologies must not be registered until they are completely constructed.
-     * Specifically, not in the constructor of Chronology.
-     *
-     * @param chrono the chronology to register; not null
-     * @return the already registered Chronology if any, may be null
-     */
-    static Chronology registerChrono(Chronology chrono) {
-        return registerChrono(chrono, chrono.getId());
-    }
-
-    /**
-     * Register a Chronology by ID and type for lookup by {@link #of(java.lang.String)}.
-     * Chronos must not be registered until they are completely constructed.
-     * Specifically, not in the constructor of Chronology.
-     *
-     * @param chrono the chronology to register; not null
-     * @param id the ID to register the chronology; not null
-     * @return the already registered Chronology if any, may be null
-     */
-    static Chronology registerChrono(Chronology chrono, String id) {
-        Chronology prev = CHRONOS_BY_ID.putIfAbsent(id, chrono);
-        if (prev == null) {
-            String type = chrono.getCalendarType();
-            if (type != null) {
-                CHRONOS_BY_TYPE.putIfAbsent(type, chrono);
-            }
-        }
-        return prev;
-    }
-
-    /**
-     * Initialization of the maps from id and type to Chronology.
-     * The ServiceLoader is used to find and register any implementations
-     * of {@link java.time.chrono.Chronology} found in the bootclass loader.
-     * The built-in chronologies are registered explicitly.
-     * Calendars configured via the Thread's context classloader are local
-     * to that thread and are ignored.
-     * <p>
-     * The initialization is done only once using the registration
-     * of the IsoChronology as the test and the final step.
-     * Multiple threads may perform the initialization concurrently.
-     * Only the first registration of each Chronology is retained by the
-     * ConcurrentHashMap.
-     * @return true if the cache was initialized
-     */
-    private static boolean initCache() {
-        if (CHRONOS_BY_ID.get("ISO") == null) {
-            // Initialization is incomplete
-
-            // Register built-in Chronologies
-            registerChrono(HijrahChronology.INSTANCE);
-            registerChrono(JapaneseChronology.INSTANCE);
-            registerChrono(MinguoChronology.INSTANCE);
-            registerChrono(ThaiBuddhistChronology.INSTANCE);
-
-            // Register Chronologies from the ServiceLoader
-            @SuppressWarnings("rawtypes")
-            ServiceLoader<Chronology> loader =  ServiceLoader.load(Chronology.class, null);
-            for (Chronology chrono : loader) {
-                String id = chrono.getId();
-                if (id.equals("ISO") || registerChrono(chrono) != null) {
-                    // Log the attempt to replace an existing Chronology
-                    PlatformLogger logger = PlatformLogger.getLogger("java.time.chrono");
-                    logger.warning("Ignoring duplicate Chronology, from ServiceLoader configuration "  + id);
-                }
-            }
-
-            // finally, register IsoChronology to mark initialization is complete
-            registerChrono(IsoChronology.INSTANCE);
-            return true;
-        }
-        return false;
-    }
-
-    //-----------------------------------------------------------------------
-    /**
      * Obtains an instance of {@code Chronology} from a temporal object.
      * <p>
      * This obtains a chronology based on the specified temporal.
@@ -320,7 +172,7 @@
      * @return the chronology, not null
      * @throws DateTimeException if unable to convert to an {@code Chronology}
      */
-    public static Chronology from(TemporalAccessor temporal) {
+    static Chronology from(TemporalAccessor temporal) {
         Objects.requireNonNull(temporal, "temporal");
         Chronology obj = temporal.query(TemporalQuery.chronology());
         return (obj != null ? obj : IsoChronology.INSTANCE);
@@ -367,31 +219,8 @@
      * @return the calendar system associated with the locale, not null
      * @throws DateTimeException if the locale-specified calendar cannot be found
      */
-    public static Chronology ofLocale(Locale locale) {
-        Objects.requireNonNull(locale, "locale");
-        String type = locale.getUnicodeLocaleType("ca");
-        if (type == null || "iso".equals(type) || "iso8601".equals(type)) {
-            return IsoChronology.INSTANCE;
-        }
-        // Not pre-defined; lookup by the type
-        do {
-            Chronology chrono = CHRONOS_BY_TYPE.get(type);
-            if (chrono != null) {
-                return chrono;
-            }
-            // If not found, do the initialization (once) and repeat the lookup
-        } while (initCache());
-
-        // Look for a Chronology using ServiceLoader of the Thread's ContextClassLoader
-        // Application provided Chronologies must not be cached
-        @SuppressWarnings("rawtypes")
-        ServiceLoader<Chronology> loader = ServiceLoader.load(Chronology.class);
-        for (Chronology chrono : loader) {
-            if (type.equals(chrono.getCalendarType())) {
-                return chrono;
-            }
-        }
-        throw new DateTimeException("Unknown calendar system: " + type);
+    static Chronology ofLocale(Locale locale) {
+        return AbstractChronology.ofLocale(locale);
     }
 
     //-----------------------------------------------------------------------
@@ -415,41 +244,8 @@
      * @return the chronology with the identifier requested, not null
      * @throws DateTimeException if the chronology cannot be found
      */
-    public static Chronology of(String id) {
-        Objects.requireNonNull(id, "id");
-        do {
-            Chronology chrono = of0(id);
-            if (chrono != null) {
-                return chrono;
-            }
-            // If not found, do the initialization (once) and repeat the lookup
-        } while (initCache());
-
-        // Look for a Chronology using ServiceLoader of the Thread's ContextClassLoader
-        // Application provided Chronologies must not be cached
-        @SuppressWarnings("rawtypes")
-        ServiceLoader<Chronology> loader = ServiceLoader.load(Chronology.class);
-        for (Chronology chrono : loader) {
-            if (id.equals(chrono.getId()) || id.equals(chrono.getCalendarType())) {
-                return chrono;
-            }
-        }
-        throw new DateTimeException("Unknown chronology: " + id);
-    }
-
-    /**
-     * Obtains an instance of {@code Chronology} from a chronology ID or
-     * calendar system type.
-     *
-     * @param id  the chronology ID or calendar system type, not null
-     * @return the chronology with the identifier requested, or {@code null} if not found
-     */
-    private static Chronology of0(String id) {
-        Chronology chrono = CHRONOS_BY_ID.get(id);
-        if (chrono == null) {
-            chrono = CHRONOS_BY_TYPE.get(id);
-        }
-        return chrono;
+    static Chronology of(String id) {
+        return AbstractChronology.of(id);
     }
 
     /**
@@ -462,24 +258,8 @@
      *
      * @return the independent, modifiable set of the available chronology IDs, not null
      */
-    public static Set<Chronology> getAvailableChronologies() {
-        initCache();       // force initialization
-        HashSet<Chronology> chronos = new HashSet<>(CHRONOS_BY_ID.values());
-
-        /// Add in Chronologies from the ServiceLoader configuration
-        @SuppressWarnings("rawtypes")
-        ServiceLoader<Chronology> loader = ServiceLoader.load(Chronology.class);
-        for (Chronology chrono : loader) {
-            chronos.add(chrono);
-        }
-        return chronos;
-    }
-
-    //-----------------------------------------------------------------------
-    /**
-     * Creates an instance.
-     */
-    protected Chronology() {
+    static Set<Chronology> getAvailableChronologies() {
+        return AbstractChronology.getAvailableChronologies();
     }
 
     //-----------------------------------------------------------------------
@@ -492,7 +272,7 @@
      * @return the chronology ID, not null
      * @see #getCalendarType()
      */
-    public abstract String getId();
+    String getId();
 
     /**
      * Gets the calendar type of the calendar system.
@@ -507,13 +287,17 @@
      * @return the calendar system type, null if the calendar is not defined by CLDR/LDML
      * @see #getId()
      */
-    public abstract String getCalendarType();
+    String getCalendarType();
 
     //-----------------------------------------------------------------------
     /**
      * Obtains a local date in this chronology from the era, year-of-era,
      * month-of-year and day-of-month fields.
      *
+     * @implSpec
+     * The default implementation combines the era and year-of-era into a proleptic
+     * year before calling {@link #date(int, int, int)}.
+     *
      * @param era  the era of the correct type for the chronology, not null
      * @param yearOfEra  the chronology year-of-era
      * @param month  the chronology month-of-year
@@ -522,7 +306,7 @@
      * @throws DateTimeException if unable to create the date
      * @throws ClassCastException if the {@code era} is not of the correct type for the chronology
      */
-    public ChronoLocalDate date(Era era, int yearOfEra, int month, int dayOfMonth) {
+    default ChronoLocalDate date(Era era, int yearOfEra, int month, int dayOfMonth) {
         return date(prolepticYear(era, yearOfEra), month, dayOfMonth);
     }
 
@@ -536,12 +320,16 @@
      * @return the local date in this chronology, not null
      * @throws DateTimeException if unable to create the date
      */
-    public abstract ChronoLocalDate date(int prolepticYear, int month, int dayOfMonth);
+    ChronoLocalDate date(int prolepticYear, int month, int dayOfMonth);
 
     /**
      * Obtains a local date in this chronology from the era, year-of-era and
      * day-of-year fields.
      *
+     * @implSpec
+     * The default implementation combines the era and year-of-era into a proleptic
+     * year before calling {@link #dateYearDay(int, int)}.
+     *
      * @param era  the era of the correct type for the chronology, not null
      * @param yearOfEra  the chronology year-of-era
      * @param dayOfYear  the chronology day-of-year
@@ -549,7 +337,7 @@
      * @throws DateTimeException if unable to create the date
      * @throws ClassCastException if the {@code era} is not of the correct type for the chronology
      */
-    public ChronoLocalDate dateYearDay(Era era, int yearOfEra, int dayOfYear) {
+    default ChronoLocalDate dateYearDay(Era era, int yearOfEra, int dayOfYear) {
         return dateYearDay(prolepticYear(era, yearOfEra), dayOfYear);
     }
 
@@ -562,7 +350,7 @@
      * @return the local date in this chronology, not null
      * @throws DateTimeException if unable to create the date
      */
-    public abstract ChronoLocalDate dateYearDay(int prolepticYear, int dayOfYear);
+    ChronoLocalDate dateYearDay(int prolepticYear, int dayOfYear);
 
     /**
      * Obtains a local date in this chronology from the epoch-day.
@@ -574,7 +362,7 @@
      * @return the local date in this chronology, not null
      * @throws DateTimeException if unable to create the date
      */
-    public abstract ChronoLocalDate dateEpochDay(long epochDay);
+    ChronoLocalDate dateEpochDay(long epochDay);
 
     //-----------------------------------------------------------------------
     /**
@@ -585,13 +373,14 @@
      * <p>
      * Using this method will prevent the ability to use an alternate clock for testing
      * because the clock is hard-coded.
-     * <p>
-     * This implementation uses {@link #dateNow(Clock)}.
+     *
+     * @implSpec
+     * The default implementation invokes {@link #dateNow(Clock)}.
      *
      * @return the current local date using the system clock and default time-zone, not null
      * @throws DateTimeException if unable to create the date
      */
-    public ChronoLocalDate dateNow() {
+    default ChronoLocalDate dateNow() {
         return dateNow(Clock.systemDefaultZone());
     }
 
@@ -604,11 +393,14 @@
      * Using this method will prevent the ability to use an alternate clock for testing
      * because the clock is hard-coded.
      *
+     * @implSpec
+     * The default implementation invokes {@link #dateNow(Clock)}.
+     *
      * @param zone  the zone ID to use, not null
      * @return the current local date using the system clock, not null
      * @throws DateTimeException if unable to create the date
      */
-    public ChronoLocalDate dateNow(ZoneId zone) {
+    default ChronoLocalDate dateNow(ZoneId zone) {
         return dateNow(Clock.system(zone));
     }
 
@@ -619,11 +411,14 @@
      * Using this method allows the use of an alternate clock for testing.
      * The alternate clock may be introduced using {@link Clock dependency injection}.
      *
+     * @implSpec
+     * The default implementation invokes {@link #date(TemporalAccessor)} )}.
+     *
      * @param clock  the clock to use, not null
      * @return the current local date, not null
      * @throws DateTimeException if unable to create the date
      */
-    public ChronoLocalDate dateNow(Clock clock) {
+    default ChronoLocalDate dateNow(Clock clock) {
         Objects.requireNonNull(clock, "clock");
         return date(LocalDate.now(clock));
     }
@@ -647,7 +442,7 @@
      * @throws DateTimeException if unable to create the date
      * @see ChronoLocalDate#from(TemporalAccessor)
      */
-    public abstract ChronoLocalDate date(TemporalAccessor temporal);
+    ChronoLocalDate date(TemporalAccessor temporal);
 
     /**
      * Obtains a local date-time in this chronology from another temporal object.
@@ -670,7 +465,7 @@
      * @throws DateTimeException if unable to create the date-time
      * @see ChronoLocalDateTime#from(TemporalAccessor)
      */
-    public ChronoLocalDateTime<? extends ChronoLocalDate> localDateTime(TemporalAccessor temporal) {
+    default ChronoLocalDateTime<? extends ChronoLocalDate> localDateTime(TemporalAccessor temporal) {
         try {
             return date(temporal).atTime(LocalTime.from(temporal));
         } catch (DateTimeException ex) {
@@ -702,7 +497,7 @@
      * @throws DateTimeException if unable to create the date-time
      * @see ChronoZonedDateTime#from(TemporalAccessor)
      */
-    public ChronoZonedDateTime<? extends ChronoLocalDate> zonedDateTime(TemporalAccessor temporal) {
+    default ChronoZonedDateTime<? extends ChronoLocalDate> zonedDateTime(TemporalAccessor temporal) {
         try {
             ZoneId zone = ZoneId.from(temporal);
             try {
@@ -728,7 +523,7 @@
      * @return the zoned date-time, not null
      * @throws DateTimeException if the result exceeds the supported range
      */
-    public ChronoZonedDateTime<? extends ChronoLocalDate> zonedDateTime(Instant instant, ZoneId zone) {
+    default ChronoZonedDateTime<? extends ChronoLocalDate> zonedDateTime(Instant instant, ZoneId zone) {
         return ChronoZonedDateTimeImpl.ofInstant(this, instant, zone);
     }
 
@@ -746,7 +541,7 @@
      * @param prolepticYear  the proleptic-year to check, not validated for range
      * @return true if the year is a leap year
      */
-    public abstract boolean isLeapYear(long prolepticYear);
+    boolean isLeapYear(long prolepticYear);
 
     /**
      * Calculates the proleptic-year given the era and year-of-era.
@@ -764,7 +559,7 @@
      *  such as if the year is invalid for the era
      * @throws ClassCastException if the {@code era} is not of the correct type for the chronology
      */
-    public abstract int prolepticYear(Era era, int yearOfEra);
+    int prolepticYear(Era era, int yearOfEra);
 
     /**
      * Creates the chronology era object from the numeric value.
@@ -785,7 +580,7 @@
      * @return the calendar system era, not null
      * @throws DateTimeException if unable to create the era
      */
-    public abstract Era eraOf(int eraValue);
+    Era eraOf(int eraValue);
 
     /**
      * Gets the list of eras for the chronology.
@@ -796,7 +591,7 @@
      *
      * @return the list of eras for the chronology, may be immutable, not null
      */
-    public abstract List<Era> eras();
+    List<Era> eras();
 
     //-----------------------------------------------------------------------
     /**
@@ -815,7 +610,7 @@
      * @return the range of valid values for the field, not null
      * @throws DateTimeException if the range for the field cannot be obtained
      */
-    public abstract ValueRange range(ChronoField field);
+    ValueRange range(ChronoField field);
 
     //-----------------------------------------------------------------------
     /**
@@ -825,28 +620,16 @@
      * suitable for presentation to the user.
      * The parameters control the style of the returned text and the locale.
      *
+     * @implSpec
+     * The default implementation behaves as the the formatter was used to
+     * format the chronology textual name.
+     *
      * @param style  the style of the text required, not null
      * @param locale  the locale to use, not null
      * @return the text value of the chronology, not null
      */
-    public String getDisplayName(TextStyle style, Locale locale) {
-        return new DateTimeFormatterBuilder().appendChronologyText(style).toFormatter(locale).format(toTemporal());
-    }
-
-    /**
-     * Converts this chronology to a {@code TemporalAccessor}.
-     * <p>
-     * A {@code Chronology} can be fully represented as a {@code TemporalAccessor}.
-     * However, the interface is not implemented by this class as most of the
-     * methods on the interface have no meaning to {@code Chronology}.
-     * <p>
-     * The returned temporal has no supported fields, with the query method
-     * supporting the return of the chronology using {@link TemporalQuery#chronology()}.
-     *
-     * @return a temporal equivalent to this chronology, not null
-     */
-    private TemporalAccessor toTemporal() {
-        return new TemporalAccessor() {
+    default String getDisplayName(TextStyle style, Locale locale) {
+        TemporalAccessor temporal = new TemporalAccessor() {
             @Override
             public boolean isSupported(TemporalField field) {
                 return false;
@@ -864,6 +647,7 @@
                 return TemporalAccessor.super.query(query);
             }
         };
+        return new DateTimeFormatterBuilder().appendChronologyText(style).toFormatter(locale).format(temporal);
     }
 
     //-----------------------------------------------------------------------
@@ -876,82 +660,8 @@
      * As such, {@code ChronoField} date fields are resolved here in the
      * context of a specific chronology.
      * <p>
-     * {@code ChronoField} instances are resolved by this method, which may
-     * be overridden in subclasses.
-     * <ul>
-     * <li>{@code EPOCH_DAY} - If present, this is converted to a date and
-     *  all other date fields are then cross-checked against the date.
-     * <li>{@code PROLEPTIC_MONTH} - If present, then it is split into the
-     *  {@code YEAR} and {@code MONTH_OF_YEAR}. If the mode is strict or smart
-     *  then the field is validated.
-     * <li>{@code YEAR_OF_ERA} and {@code ERA} - If both are present, then they
-     *  are combined to form a {@code YEAR}. In lenient mode, the {@code YEAR_OF_ERA}
-     *  range is not validated, in smart and strict mode it is. The {@code ERA} is
-     *  validated for range in all three modes. If only the {@code YEAR_OF_ERA} is
-     *  present, and the mode is smart or lenient, then the last available era
-     *  is assumed. In strict mode, no era is assumed and the {@code YEAR_OF_ERA} is
-     *  left untouched. If only the {@code ERA} is present, then it is left untouched.
-     * <li>{@code YEAR}, {@code MONTH_OF_YEAR} and {@code DAY_OF_MONTH} -
-     *  If all three are present, then they are combined to form a date.
-     *  In all three modes, the {@code YEAR} is validated.
-     *  If the mode is smart or strict, then the month and day are validated.
-     *  If the mode is lenient, then the date is combined in a manner equivalent to
-     *  creating a date on the first day of the first month in the requested year,
-     *  then adding the difference in months, then the difference in days.
-     *  If the mode is smart, and the day-of-month is greater than the maximum for
-     *  the year-month, then the day-of-month is adjusted to the last day-of-month.
-     *  If the mode is strict, then the three fields must form a valid date.
-     * <li>{@code YEAR} and {@code DAY_OF_YEAR} -
-     *  If both are present, then they are combined to form a date.
-     *  In all three modes, the {@code YEAR} is validated.
-     *  If the mode is lenient, then the date is combined in a manner equivalent to
-     *  creating a date on the first day of the requested year, then adding
-     *  the difference in days.
-     *  If the mode is smart or strict, then the two fields must form a valid date.
-     * <li>{@code YEAR}, {@code MONTH_OF_YEAR}, {@code ALIGNED_WEEK_OF_MONTH} and
-     *  {@code ALIGNED_DAY_OF_WEEK_IN_MONTH} -
-     *  If all four are present, then they are combined to form a date.
-     *  In all three modes, the {@code YEAR} is validated.
-     *  If the mode is lenient, then the date is combined in a manner equivalent to
-     *  creating a date on the first day of the first month in the requested year, then adding
-     *  the difference in months, then the difference in weeks, then in days.
-     *  If the mode is smart or strict, then the all four fields are validated to
-     *  their outer ranges. The date is then combined in a manner equivalent to
-     *  creating a date on the first day of the requested year and month, then adding
-     *  the amount in weeks and days to reach their values. If the mode is strict,
-     *  the date is additionally validated to check that the day and week adjustment
-     *  did not change the month.
-     * <li>{@code YEAR}, {@code MONTH_OF_YEAR}, {@code ALIGNED_WEEK_OF_MONTH} and
-     *  {@code DAY_OF_WEEK} - If all four are present, then they are combined to
-     *  form a date. The approach is the same as described above for
-     *  years, months and weeks in {@code ALIGNED_DAY_OF_WEEK_IN_MONTH}.
-     *  The day-of-week is adjusted as the next or same matching day-of-week once
-     *  the years, months and weeks have been handled.
-     * <li>{@code YEAR}, {@code ALIGNED_WEEK_OF_YEAR} and {@code ALIGNED_DAY_OF_WEEK_IN_YEAR} -
-     *  If all three are present, then they are combined to form a date.
-     *  In all three modes, the {@code YEAR} is validated.
-     *  If the mode is lenient, then the date is combined in a manner equivalent to
-     *  creating a date on the first day of the requested year, then adding
-     *  the difference in weeks, then in days.
-     *  If the mode is smart or strict, then the all three fields are validated to
-     *  their outer ranges. The date is then combined in a manner equivalent to
-     *  creating a date on the first day of the requested year, then adding
-     *  the amount in weeks and days to reach their values. If the mode is strict,
-     *  the date is additionally validated to check that the day and week adjustment
-     *  did not change the year.
-     * <li>{@code YEAR}, {@code ALIGNED_WEEK_OF_YEAR} and {@code DAY_OF_WEEK} -
-     *  If all three are present, then they are combined to form a date.
-     *  The approach is the same as described above for years and weeks in
-     *  {@code ALIGNED_DAY_OF_WEEK_IN_YEAR}. The day-of-week is adjusted as the
-     *  next or same matching day-of-week once the years and weeks have been handled.
-     * </ul>
-     * <p>
-     * The default implementation is suitable for most calendar systems.
-     * If {@link ChronoField#YEAR_OF_ERA} is found without an {@link ChronoField#ERA}
-     * then the last era in {@link #eras()} is used.
-     * The implementation assumes a 7 day week, that the first day-of-month
-     * has the value 1, that first day-of-year has the value 1, and that the
-     * first of the month and year always exists.
+     * The default implementation, which explains typical resolve behaviour,
+     * is provided in {@link AbstractChronology}.
      *
      * @param fieldValues  the map of fields to values, which can be updated, not null
      * @param resolverStyle  the requested type of resolve, not null
@@ -959,233 +669,7 @@
      * @throws DateTimeException if the date cannot be resolved, typically
      *  because of a conflict in the input data
      */
-    public ChronoLocalDate resolveDate(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
-        // check epoch-day before inventing era
-        if (fieldValues.containsKey(EPOCH_DAY)) {
-            return dateEpochDay(fieldValues.remove(EPOCH_DAY));
-        }
-
-        // fix proleptic month before inventing era
-        resolveProlepticMonth(fieldValues, resolverStyle);
-
-        // invent era if necessary to resolve year-of-era
-        ChronoLocalDate resolved = resolveYearOfEra(fieldValues, resolverStyle);
-        if (resolved != null) {
-            return resolved;
-        }
-
-        // build date
-        if (fieldValues.containsKey(YEAR)) {
-            if (fieldValues.containsKey(MONTH_OF_YEAR)) {
-                if (fieldValues.containsKey(DAY_OF_MONTH)) {
-                    return resolveYMD(fieldValues, resolverStyle);
-                }
-                if (fieldValues.containsKey(ALIGNED_WEEK_OF_MONTH)) {
-                    if (fieldValues.containsKey(ALIGNED_DAY_OF_WEEK_IN_MONTH)) {
-                        return resolveYMAA(fieldValues, resolverStyle);
-                    }
-                    if (fieldValues.containsKey(DAY_OF_WEEK)) {
-                        return resolveYMAD(fieldValues, resolverStyle);
-                    }
-                }
-            }
-            if (fieldValues.containsKey(DAY_OF_YEAR)) {
-                return resolveYD(fieldValues, resolverStyle);
-            }
-            if (fieldValues.containsKey(ALIGNED_WEEK_OF_YEAR)) {
-                if (fieldValues.containsKey(ALIGNED_DAY_OF_WEEK_IN_YEAR)) {
-                    return resolveYAA(fieldValues, resolverStyle);
-                }
-                if (fieldValues.containsKey(DAY_OF_WEEK)) {
-                    return resolveYAD(fieldValues, resolverStyle);
-                }
-            }
-        }
-        return null;
-    }
-
-    void resolveProlepticMonth(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
-        Long pMonth = fieldValues.remove(PROLEPTIC_MONTH);
-        if (pMonth != null) {
-            if (resolverStyle != ResolverStyle.LENIENT) {
-                PROLEPTIC_MONTH.checkValidValue(pMonth);
-            }
-            // first day-of-month is likely to be safest for setting proleptic-month
-            // cannot add to year zero, as not all chronologies have a year zero
-            ChronoLocalDate chronoDate = dateNow()
-                    .with(DAY_OF_MONTH, 1).with(PROLEPTIC_MONTH, pMonth);
-            addFieldValue(fieldValues, MONTH_OF_YEAR, chronoDate.get(MONTH_OF_YEAR));
-            addFieldValue(fieldValues, YEAR, chronoDate.get(YEAR));
-        }
-    }
-
-    ChronoLocalDate resolveYearOfEra(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
-        Long yoeLong = fieldValues.remove(YEAR_OF_ERA);
-        if (yoeLong != null) {
-            Long eraLong = fieldValues.remove(ERA);
-            int yoe;
-            if (resolverStyle != ResolverStyle.LENIENT) {
-                yoe = range(YEAR_OF_ERA).checkValidIntValue(yoeLong, YEAR_OF_ERA);
-            } else {
-                yoe = Math.toIntExact(yoeLong);
-            }
-            if (eraLong != null) {
-                Era eraObj = eraOf(range(ERA).checkValidIntValue(eraLong, ERA));
-                addFieldValue(fieldValues, YEAR, prolepticYear(eraObj, yoe));
-            } else {
-                if (fieldValues.containsKey(YEAR)) {
-                    int year = range(YEAR).checkValidIntValue(fieldValues.get(YEAR), YEAR);
-                    ChronoLocalDate chronoDate = dateYearDay(year, 1);
-                    addFieldValue(fieldValues, YEAR, prolepticYear(chronoDate.getEra(), yoe));
-                } else if (resolverStyle == ResolverStyle.STRICT) {
-                    // do not invent era if strict
-                    // reinstate the field removed earlier, no cross-check issues
-                    fieldValues.put(YEAR_OF_ERA, yoeLong);
-                } else {
-                    List<Era> eras = eras();
-                    if (eras.isEmpty()) {
-                        addFieldValue(fieldValues, YEAR, yoe);
-                    } else {
-                        Era eraObj = eras.get(eras.size() - 1);
-                        addFieldValue(fieldValues, YEAR, prolepticYear(eraObj, yoe));
-                    }
-                }
-            }
-        } else if (fieldValues.containsKey(ERA)) {
-            range(ERA).checkValidValue(fieldValues.get(ERA), ERA);  // always validated
-        }
-        return null;
-    }
-
-    ChronoLocalDate resolveYMD(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
-        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
-        if (resolverStyle == ResolverStyle.LENIENT) {
-            long months = Math.subtractExact(fieldValues.remove(MONTH_OF_YEAR), 1);
-            long days = Math.subtractExact(fieldValues.remove(DAY_OF_MONTH), 1);
-            return date(y, 1, 1).plus(months, MONTHS).plus(days, DAYS);
-        }
-        int moy = range(MONTH_OF_YEAR).checkValidIntValue(fieldValues.remove(MONTH_OF_YEAR), MONTH_OF_YEAR);
-        ValueRange domRange = range(DAY_OF_MONTH);
-        int dom = domRange.checkValidIntValue(fieldValues.remove(DAY_OF_MONTH), DAY_OF_MONTH);
-        if (resolverStyle == ResolverStyle.SMART) {  // previous valid
-            try {
-                return date(y, moy, dom);
-            } catch (DateTimeException ex) {
-                return date(y, moy, 1).with(TemporalAdjuster.lastDayOfMonth());
-            }
-        }
-        return date(y, moy, dom);
-    }
-
-    ChronoLocalDate resolveYD(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
-        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
-        if (resolverStyle == ResolverStyle.LENIENT) {
-            long days = Math.subtractExact(fieldValues.remove(DAY_OF_YEAR), 1);
-            return dateYearDay(y, 1).plus(days, DAYS);
-        }
-        int doy = range(DAY_OF_YEAR).checkValidIntValue(fieldValues.remove(DAY_OF_YEAR), DAY_OF_YEAR);
-        return dateYearDay(y, doy);  // smart is same as strict
-    }
-
-    ChronoLocalDate resolveYMAA(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
-        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
-        if (resolverStyle == ResolverStyle.LENIENT) {
-            long months = Math.subtractExact(fieldValues.remove(MONTH_OF_YEAR), 1);
-            long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), 1);
-            long days = Math.subtractExact(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_MONTH), 1);
-            return date(y, 1, 1).plus(months, MONTHS).plus(weeks, WEEKS).plus(days, DAYS);
-        }
-        int moy = range(MONTH_OF_YEAR).checkValidIntValue(fieldValues.remove(MONTH_OF_YEAR), MONTH_OF_YEAR);
-        int aw = range(ALIGNED_WEEK_OF_MONTH).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), ALIGNED_WEEK_OF_MONTH);
-        int ad = range(ALIGNED_DAY_OF_WEEK_IN_MONTH).checkValidIntValue(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_MONTH), ALIGNED_DAY_OF_WEEK_IN_MONTH);
-        ChronoLocalDate date = date(y, moy, 1).plus((aw - 1) * 7 + (ad - 1), DAYS);
-        if (resolverStyle == ResolverStyle.STRICT && date.get(MONTH_OF_YEAR) != moy) {
-            throw new DateTimeException("Strict mode rejected resolved date as it is in a different month");
-        }
-        return date;
-    }
-
-    ChronoLocalDate resolveYMAD(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
-        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
-        if (resolverStyle == ResolverStyle.LENIENT) {
-            long months = Math.subtractExact(fieldValues.remove(MONTH_OF_YEAR), 1);
-            long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), 1);
-            long dow = Math.subtractExact(fieldValues.remove(DAY_OF_WEEK), 1);
-            return resolveAligned(date(y, 1, 1), months, weeks, dow);
-        }
-        int moy = range(MONTH_OF_YEAR).checkValidIntValue(fieldValues.remove(MONTH_OF_YEAR), MONTH_OF_YEAR);
-        int aw = range(ALIGNED_WEEK_OF_MONTH).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), ALIGNED_WEEK_OF_MONTH);
-        int dow = range(DAY_OF_WEEK).checkValidIntValue(fieldValues.remove(DAY_OF_WEEK), DAY_OF_WEEK);
-        ChronoLocalDate date = date(y, moy, 1).plus((aw - 1) * 7, DAYS).with(nextOrSame(DayOfWeek.of(dow)));
-        if (resolverStyle == ResolverStyle.STRICT && date.get(MONTH_OF_YEAR) != moy) {
-            throw new DateTimeException("Strict mode rejected resolved date as it is in a different month");
-        }
-        return date;
-    }
-
-    ChronoLocalDate resolveYAA(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
-        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
-        if (resolverStyle == ResolverStyle.LENIENT) {
-            long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), 1);
-            long days = Math.subtractExact(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_YEAR), 1);
-            return dateYearDay(y, 1).plus(weeks, WEEKS).plus(days, DAYS);
-        }
-        int aw = range(ALIGNED_WEEK_OF_YEAR).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), ALIGNED_WEEK_OF_YEAR);
-        int ad = range(ALIGNED_DAY_OF_WEEK_IN_YEAR).checkValidIntValue(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_YEAR), ALIGNED_DAY_OF_WEEK_IN_YEAR);
-        ChronoLocalDate date = dateYearDay(y, 1).plus((aw - 1) * 7 + (ad - 1), DAYS);
-        if (resolverStyle == ResolverStyle.STRICT && date.get(YEAR) != y) {
-            throw new DateTimeException("Strict mode rejected resolved date as it is in a different year");
-        }
-        return date;
-    }
-
-    ChronoLocalDate resolveYAD(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle) {
-        int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR);
-        if (resolverStyle == ResolverStyle.LENIENT) {
-            long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), 1);
-            long dow = Math.subtractExact(fieldValues.remove(DAY_OF_WEEK), 1);
-            return resolveAligned(dateYearDay(y, 1), 0, weeks, dow);
-        }
-        int aw = range(ALIGNED_WEEK_OF_YEAR).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), ALIGNED_WEEK_OF_YEAR);
-        int dow = range(DAY_OF_WEEK).checkValidIntValue(fieldValues.remove(DAY_OF_WEEK), DAY_OF_WEEK);
-        ChronoLocalDate date = dateYearDay(y, 1).plus((aw - 1) * 7, DAYS).with(nextOrSame(DayOfWeek.of(dow)));
-        if (resolverStyle == ResolverStyle.STRICT && date.get(YEAR) != y) {
-            throw new DateTimeException("Strict mode rejected resolved date as it is in a different year");
-        }
-        return date;
-    }
-
-    ChronoLocalDate resolveAligned(ChronoLocalDate base, long months, long weeks, long dow) {
-        ChronoLocalDate date = base.plus(months, MONTHS).plus(weeks, WEEKS);
-        if (dow > 7) {
-            date = date.plus((dow - 1) / 7, WEEKS);
-            dow = ((dow - 1) % 7) + 1;
-        } else if (dow < 1) {
-            date = date.plus(Math.subtractExact(dow,  7) / 7, WEEKS);
-            dow = ((dow + 6) % 7) + 1;
-        }
-        return date.with(nextOrSame(DayOfWeek.of((int) dow)));
-    }
-
-    /**
-     * Adds a field-value pair to the map, checking for conflicts.
-     * <p>
-     * If the field is not already present, then the field-value pair is added to the map.
-     * If the field is already present and it has the same value as that specified, no action occurs.
-     * If the field is already present and it has a different value to that specified, then
-     * an exception is thrown.
-     *
-     * @param field  the field to add, not null
-     * @param value  the value to add, not null
-     * @throws DateTimeException if the field is already present with a different value
-     */
-    void addFieldValue(Map<TemporalField, Long> fieldValues, ChronoField field, long value) {
-        Long old = fieldValues.get(field);  // check first for better error message
-        if (old != null && old.longValue() != value) {
-            throw new DateTimeException("Conflict found: " + field + " " + old + " differs from " + field + " " + value);
-        }
-        fieldValues.put(field, value);
-    }
+    ChronoLocalDate resolveDate(Map<TemporalField, Long> fieldValues, ResolverStyle resolverStyle);
 
     //-----------------------------------------------------------------------
     /**
@@ -1215,7 +699,7 @@
      * @param days  the number of years, may be negative
      * @return the period in terms of this chronology, not null
      */
-    public ChronoPeriod period(int years, int months, int days) {
+    default ChronoPeriod period(int years, int months, int days) {
         return new ChronoPeriodImpl(this, years, months, days);
     }
 
@@ -1226,107 +710,43 @@
      * The comparison order first by the chronology ID string, then by any
      * additional information specific to the subclass.
      * It is "consistent with equals", as defined by {@link Comparable}.
-     * <p>
-     * The default implementation compares the chronology ID.
-     * Subclasses must compare any additional state that they store.
      *
      * @param other  the other chronology to compare to, not null
      * @return the comparator value, negative if less, positive if greater
      */
     @Override
-    public int compareTo(Chronology other) {
-        return getId().compareTo(other.getId());
-    }
+    int compareTo(Chronology other);
 
     /**
      * Checks if this chronology is equal to another chronology.
      * <p>
      * The comparison is based on the entire state of the object.
-     * <p>
-     * The default implementation checks the type and calls {@link #compareTo(Chronology)}.
      *
      * @param obj  the object to check, null returns false
      * @return true if this is equal to the other chronology
      */
     @Override
-    public boolean equals(Object obj) {
-        if (this == obj) {
-           return true;
-        }
-        if (obj instanceof Chronology) {
-            return compareTo((Chronology) obj) == 0;
-        }
-        return false;
-    }
+    boolean equals(Object obj);
 
     /**
      * A hash code for this chronology.
      * <p>
-     * The default implementation is based on the ID and class.
-     * Subclasses should add any additional state that they store.
+     * The hash code should be based on the entire state of the object.
      *
      * @return a suitable hash code
      */
     @Override
-    public int hashCode() {
-        return getClass().hashCode() ^ getId().hashCode();
-    }
+    int hashCode();
 
     //-----------------------------------------------------------------------
     /**
-     * Outputs this chronology as a {@code String}, using the ID.
+     * Outputs this chronology as a {@code String}.
+     * <p>
+     * The format should include the entire state of the object.
      *
      * @return a string representation of this chronology, not null
      */
     @Override
-    public String toString() {
-        return getId();
-    }
-
-    //-----------------------------------------------------------------------
-    /**
-     * Writes the Chronology using a
-     * <a href="../../../serialized-form.html#java.time.chrono.Ser">dedicated serialized form</a>.
-     * @serialData
-     * <pre>
-     *  out.writeByte(1);  // identifies a Chronology
-     *  out.writeUTF(getId());
-     * </pre>
-     *
-     * @return the instance of {@code Ser}, not null
-     */
-    Object writeReplace() {
-        return new Ser(Ser.CHRONO_TYPE, this);
-    }
-
-    /**
-     * Defend against malicious streams.
-     * @return never
-     * @throws InvalidObjectException always
-     */
-    private Object readResolve() throws InvalidObjectException {
-        throw new InvalidObjectException("Deserialization via serialization delegate");
-    }
-
-    /**
-     * Write the Chronology id to the stream.
-     * @param out the output stream
-     * @throws IOException on any error during the write
-     */
-    void writeExternal(DataOutput out) throws IOException {
-        out.writeUTF(getId());
-    }
-
-    /**
-     * Reads the Chronology id and creates the Chronology.
-     * @param in  the input stream
-     * @return  the Chronology
-     * @throws IOException  on errors during the read
-     * @throws DateTimeException if the Chronology cannot be returned
-     */
-    static Chronology readExternal(DataInput in) throws IOException {
-        String id = in.readUTF();
-        return Chronology.of(id);
-    }
+    String toString();
 
 }
--- a/jdk/src/share/classes/java/time/chrono/HijrahChronology.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/src/share/classes/java/time/chrono/HijrahChronology.java	Tue Jul 09 21:35:04 2013 +0100
@@ -214,7 +214,7 @@
  *
  * @since 1.8
  */
-public final class HijrahChronology extends Chronology implements Serializable {
+public final class HijrahChronology extends AbstractChronology implements Serializable {
 
     /**
      * The Hijrah Calendar id.
@@ -308,8 +308,8 @@
         try {
             INSTANCE = new HijrahChronology("Hijrah-umalqura");
             // Register it by its aliases
-            Chronology.registerChrono(INSTANCE, "Hijrah");
-            Chronology.registerChrono(INSTANCE, "islamic");
+            AbstractChronology.registerChrono(INSTANCE, "Hijrah");
+            AbstractChronology.registerChrono(INSTANCE, "islamic");
         } catch (DateTimeException ex) {
             // Absence of Hijrah calendar is fatal to initializing this class.
             PlatformLogger logger = PlatformLogger.getLogger("java.time.chrono");
@@ -336,7 +336,7 @@
                 try {
                     // Create and register the variant
                     HijrahChronology chrono = new HijrahChronology(id);
-                    Chronology.registerChrono(chrono);
+                    AbstractChronology.registerChrono(chrono);
                 } catch (DateTimeException ex) {
                     // Log error and continue
                     PlatformLogger logger = PlatformLogger.getLogger("java.time.chrono");
--- a/jdk/src/share/classes/java/time/chrono/IsoChronology.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/src/share/classes/java/time/chrono/IsoChronology.java	Tue Jul 09 21:35:04 2013 +0100
@@ -120,7 +120,7 @@
  *
  * @since 1.8
  */
-public final class IsoChronology extends Chronology implements Serializable {
+public final class IsoChronology extends AbstractChronology implements Serializable {
 
     /**
      * Singleton instance of the ISO chronology.
--- a/jdk/src/share/classes/java/time/chrono/JapaneseChronology.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/src/share/classes/java/time/chrono/JapaneseChronology.java	Tue Jul 09 21:35:04 2013 +0100
@@ -120,7 +120,7 @@
  *
  * @since 1.8
  */
-public final class JapaneseChronology extends Chronology implements Serializable {
+public final class JapaneseChronology extends AbstractChronology implements Serializable {
 
     static final LocalGregorianCalendar JCAL =
         (LocalGregorianCalendar) CalendarSystem.forName("japanese");
--- a/jdk/src/share/classes/java/time/chrono/MinguoChronology.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/src/share/classes/java/time/chrono/MinguoChronology.java	Tue Jul 09 21:35:04 2013 +0100
@@ -105,7 +105,7 @@
  *
  * @since 1.8
  */
-public final class MinguoChronology extends Chronology implements Serializable {
+public final class MinguoChronology extends AbstractChronology implements Serializable {
 
     /**
      * Singleton instance for the Minguo chronology.
--- a/jdk/src/share/classes/java/time/chrono/Ser.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/src/share/classes/java/time/chrono/Ser.java	Tue Jul 09 21:35:04 2013 +0100
@@ -161,7 +161,7 @@
         out.writeByte(type);
         switch (type) {
             case CHRONO_TYPE:
-                ((Chronology) object).writeExternal(out);
+                ((AbstractChronology) object).writeExternal(out);
                 break;
             case CHRONO_LOCAL_DATE_TIME_TYPE:
                 ((ChronoLocalDateTimeImpl<?>) object).writeExternal(out);
@@ -231,7 +231,7 @@
 
     private static Object readInternal(byte type, ObjectInput in) throws IOException, ClassNotFoundException {
         switch (type) {
-            case CHRONO_TYPE: return Chronology.readExternal(in);
+            case CHRONO_TYPE: return AbstractChronology.readExternal(in);
             case CHRONO_LOCAL_DATE_TIME_TYPE: return ChronoLocalDateTimeImpl.readExternal(in);
             case CHRONO_ZONE_DATE_TIME_TYPE: return ChronoZonedDateTimeImpl.readExternal(in);
             case JAPANESE_DATE_TYPE:  return JapaneseDate.readExternal(in);
--- a/jdk/src/share/classes/java/time/chrono/ThaiBuddhistChronology.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/src/share/classes/java/time/chrono/ThaiBuddhistChronology.java	Tue Jul 09 21:35:04 2013 +0100
@@ -106,7 +106,7 @@
  *
  * @since 1.8
  */
-public final class ThaiBuddhistChronology extends Chronology implements Serializable {
+public final class ThaiBuddhistChronology extends AbstractChronology implements Serializable {
 
     /**
      * Singleton instance of the Buddhist chronology.
--- a/jdk/test/java/time/tck/java/time/chrono/CopticChronology.java	Thu Sep 26 23:05:29 2013 -0700
+++ b/jdk/test/java/time/tck/java/time/chrono/CopticChronology.java	Tue Jul 09 21:35:04 2013 +0100
@@ -59,13 +59,11 @@
 import static java.time.temporal.ChronoField.EPOCH_DAY;
 
 import java.io.Serializable;
-
+import java.time.chrono.AbstractChronology;
+import java.time.chrono.Era;
 import java.time.temporal.ChronoField;
 import java.time.temporal.TemporalAccessor;
 import java.time.temporal.ValueRange;
-import java.time.chrono.Chronology;
-import java.time.chrono.Era;
-
 import java.util.Arrays;
 import java.util.List;
 import java.util.Locale;
@@ -95,7 +93,7 @@
  * <h4>Implementation notes</h4>
  * This class is immutable and thread-safe.
  */
-public final class CopticChronology extends Chronology implements Serializable {
+public final class CopticChronology extends AbstractChronology implements Serializable {
 
     /**
      * Singleton instance of the Coptic chronology.