jdk/src/share/classes/java/text/CalendarBuilder.java
changeset 6491 cd1bcc5057f4
child 17178 bf3ea41ef154
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/text/CalendarBuilder.java	Wed Sep 01 15:19:13 2010 +0900
@@ -0,0 +1,170 @@
+/*
+ * Copyright (c) 2010, 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.
+ */
+
+package java.text;
+
+import java.util.Calendar;
+import static java.util.GregorianCalendar.*;
+
+/**
+ * {@code CalendarBuilder} keeps field-value pairs for setting
+ * the calendar fields of the given {@code Calendar}. It has the
+ * {@link Calendar#FIELD_COUNT FIELD_COUNT}-th field for the week year
+ * support. Also {@code ISO_DAY_OF_WEEK} is used to specify
+ * {@code DAY_OF_WEEK} in the ISO day of week numbering.
+ *
+ * <p>{@code CalendarBuilder} retains the semantic of the pseudo
+ * timestamp for fields. {@code CalendarBuilder} uses a single
+ * int array combining fields[] and stamp[] of {@code Calendar}.
+ *
+ * @author Masayoshi Okutsu
+ */
+class CalendarBuilder {
+    /*
+     * Pseudo time stamp constants used in java.util.Calendar
+     */
+    private static final int UNSET = 0;
+    private static final int COMPUTED = 1;
+    private static final int MINIMUM_USER_STAMP = 2;
+
+    private static final int MAX_FIELD = FIELD_COUNT + 1;
+
+    public static final int WEEK_YEAR = FIELD_COUNT;
+    public static final int ISO_DAY_OF_WEEK = 1000; // pseudo field index
+
+    // stamp[] (lower half) and field[] (upper half) combined
+    private final int[] field;
+    private int nextStamp;
+    private int maxFieldIndex;
+
+    CalendarBuilder() {
+        field = new int[MAX_FIELD * 2];
+        nextStamp = MINIMUM_USER_STAMP;
+        maxFieldIndex = -1;
+    }
+
+    CalendarBuilder set(int index, int value) {
+        if (index == ISO_DAY_OF_WEEK) {
+            index = DAY_OF_WEEK;
+            value = toCalendarDayOfWeek(value);
+        }
+        field[index] = nextStamp++;
+        field[MAX_FIELD + index] = value;
+        if (index > maxFieldIndex && index < FIELD_COUNT) {
+            maxFieldIndex = index;
+        }
+        return this;
+    }
+
+    CalendarBuilder addYear(int value) {
+        field[MAX_FIELD + YEAR] += value;
+        field[MAX_FIELD + WEEK_YEAR] += value;
+        return this;
+    }
+
+    boolean isSet(int index) {
+        if (index == ISO_DAY_OF_WEEK) {
+            index = DAY_OF_WEEK;
+        }
+        return field[index] > UNSET;
+    }
+
+    Calendar establish(Calendar cal) {
+        boolean weekDate = isSet(WEEK_YEAR)
+                            && field[WEEK_YEAR] > field[YEAR];
+        if (weekDate && !cal.isWeekDateSupported()) {
+            // Use YEAR instead
+            if (!isSet(YEAR)) {
+                set(YEAR, field[MAX_FIELD + WEEK_YEAR]);
+            }
+            weekDate = false;
+        }
+
+        cal.clear();
+        // Set the fields from the min stamp to the max stamp so that
+        // the field resolution works in the Calendar.
+        for (int stamp = MINIMUM_USER_STAMP; stamp < nextStamp; stamp++) {
+            for (int index = 0; index <= maxFieldIndex; index++) {
+                if (field[index] == stamp) {
+                    cal.set(index, field[MAX_FIELD + index]);
+                    break;
+                }
+            }
+        }
+
+        if (weekDate) {
+            int weekOfYear = isSet(WEEK_OF_YEAR) ? field[MAX_FIELD + WEEK_OF_YEAR] : 1;
+            int dayOfWeek = isSet(DAY_OF_WEEK) ?
+                                field[MAX_FIELD + DAY_OF_WEEK] : cal.getFirstDayOfWeek();
+            if (!isValidDayOfWeek(dayOfWeek) && cal.isLenient()) {
+                if (dayOfWeek >= 8) {
+                    dayOfWeek--;
+                    weekOfYear += dayOfWeek / 7;
+                    dayOfWeek = (dayOfWeek % 7) + 1;
+                } else {
+                    while (dayOfWeek <= 0) {
+                        dayOfWeek += 7;
+                        weekOfYear--;
+                    }
+                }
+                dayOfWeek = toCalendarDayOfWeek(dayOfWeek);
+            }
+            cal.setWeekDate(field[MAX_FIELD + WEEK_YEAR], weekOfYear, dayOfWeek);
+        }
+        return cal;
+    }
+
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append("CalendarBuilder:[");
+        for (int i = 0; i < field.length; i++) {
+            if (isSet(i)) {
+                sb.append(i).append('=').append(field[MAX_FIELD + i]).append(',');
+            }
+        }
+        int lastIndex = sb.length() - 1;
+        if (sb.charAt(lastIndex) == ',') {
+            sb.setLength(lastIndex);
+        }
+        sb.append(']');
+        return sb.toString();
+    }
+
+    static int toISODayOfWeek(int calendarDayOfWeek) {
+        return calendarDayOfWeek == SUNDAY ? 7 : calendarDayOfWeek - 1;
+    }
+
+    static int toCalendarDayOfWeek(int isoDayOfWeek) {
+        if (!isValidDayOfWeek(isoDayOfWeek)) {
+            // adjust later for lenient mode
+            return isoDayOfWeek;
+        }
+        return isoDayOfWeek == 7 ? SUNDAY : isoDayOfWeek + 1;
+    }
+
+    static boolean isValidDayOfWeek(int dayOfWeek) {
+        return dayOfWeek > 0 && dayOfWeek <= 7;
+    }
+}