changeset 13970:271faffbe204

8152077: (cal) Calendar.roll does not always roll the hours during daylight savings Reviewed-by: peytoia
author okutsu
date Tue, 29 Mar 2016 18:04:41 +0900
parents ff721bdc4c68
children 841f1fe6d486
files src/java.base/share/classes/java/util/GregorianCalendar.java test/java/util/Calendar/Bug8152077.java
diffstat 2 files changed, 157 insertions(+), 26 deletions(-) [+]
line wrap: on
line diff
--- a/src/java.base/share/classes/java/util/GregorianCalendar.java	Tue Mar 29 10:47:03 2016 +0800
+++ b/src/java.base/share/classes/java/util/GregorianCalendar.java	Tue Mar 29 18:04:41 2016 +0900
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2016, 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
@@ -1189,37 +1189,33 @@
         case HOUR:
         case HOUR_OF_DAY:
             {
-                int unit = max + 1; // 12 or 24 hours
-                int h = internalGet(field);
-                int nh = (h + amount) % unit;
-                if (nh < 0) {
-                    nh += unit;
+                int rolledValue = getRolledValue(internalGet(field), amount, min, max);
+                int hourOfDay = rolledValue;
+                if (field == HOUR && internalGet(AM_PM) == PM) {
+                    hourOfDay += 12;
                 }
-                time += ONE_HOUR * (nh - h);
 
-                // The day might have changed, which could happen if
-                // the daylight saving time transition brings it to
-                // the next day, although it's very unlikely. But we
-                // have to make sure not to change the larger fields.
+                // Create the current date/time value to perform wall-clock-based
+                // roll.
                 CalendarDate d = calsys.getCalendarDate(time, getZone());
-                if (internalGet(DAY_OF_MONTH) != d.getDayOfMonth()) {
-                    d.setDate(internalGet(YEAR),
-                              internalGet(MONTH) + 1,
-                              internalGet(DAY_OF_MONTH));
-                    if (field == HOUR) {
-                        assert (internalGet(AM_PM) == PM);
-                        d.addHours(+12); // restore PM
+                d.setHours(hourOfDay);
+                time = calsys.getTime(d);
+
+                // If we stay on the same wall-clock time, try the next or previous hour.
+                if (internalGet(HOUR_OF_DAY) == d.getHours()) {
+                    hourOfDay = getRolledValue(rolledValue, amount > 0 ? +1 : -1, min, max);
+                    if (field == HOUR && internalGet(AM_PM) == PM) {
+                        hourOfDay += 12;
                     }
+                    d.setHours(hourOfDay);
                     time = calsys.getTime(d);
                 }
-                int hourOfDay = d.getHours();
-                internalSet(field, hourOfDay % unit);
-                if (field == HOUR) {
-                    internalSet(HOUR_OF_DAY, hourOfDay);
-                } else {
-                    internalSet(AM_PM, hourOfDay / 12);
-                    internalSet(HOUR, hourOfDay % 12);
-                }
+                // Get the new hourOfDay value which might have changed due to a DST transition.
+                hourOfDay = d.getHours();
+                // Update the hour related fields
+                internalSet(HOUR_OF_DAY, hourOfDay);
+                internalSet(AM_PM, hourOfDay / 12);
+                internalSet(HOUR, hourOfDay % 12);
 
                 // Time zone offset and/or daylight saving might have changed.
                 int zoneOffset = d.getZoneOffset();
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/java/util/Calendar/Bug8152077.java	Tue Mar 29 18:04:41 2016 +0900
@@ -0,0 +1,135 @@
+/*
+ * Copyright (c) 2016, 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.
+ *
+ * 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.
+ */
+
+/**
+ * @test
+ * @bug 8152077
+ * @summary Make sure that roll() with HOUR/HOUR_OF_DAY works around standard/daylight
+ *          time transitions
+ */
+
+import java.util.Calendar;
+import java.util.GregorianCalendar;
+import java.util.TimeZone;
+import static java.util.Calendar.*;
+
+public class Bug8152077 {
+    private static final TimeZone LA = TimeZone.getTimeZone("America/Los_Angeles");
+    private static final TimeZone BR = TimeZone.getTimeZone("America/Sao_Paulo");
+
+    private static final int[] ALLDAY_HOURS = {
+        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
+        12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23
+    };
+    private static final int[] AM_HOURS = {
+        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
+    };
+    private static final int[] PM_HOURS = { // in 24-hour clock
+        12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23
+    };
+
+    private static int errors;
+
+    public static void main(String[] args) {
+        TimeZone initialTz = TimeZone.getDefault();
+        try {
+            testRoll(LA, new int[] { 2016, MARCH, 13 },
+                     new int[] { 0, 1, 3, 4, 5, 6, 7, 8, 9, 10, 11,
+                         12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 });
+            testRoll(LA, new int[] { 2016, MARCH, 13 },
+                     new int[] { 0, 1, 3, 4, 5, 6, 7, 8, 9, 10, 11 });
+            testRoll(LA, new int[] { 2016, MARCH, 13 }, PM_HOURS);
+
+            testRoll(LA, new int[] { 2016, NOVEMBER, 6 }, ALLDAY_HOURS);
+            testRoll(LA, new int[] { 2016, NOVEMBER, 6 }, AM_HOURS);
+            testRoll(LA, new int[] { 2016, NOVEMBER, 6 }, PM_HOURS);
+
+            testRoll(BR, new int[] { 2016, FEBRUARY, 21 }, ALLDAY_HOURS);
+            testRoll(BR, new int[] { 2016, FEBRUARY, 21 }, AM_HOURS);
+            testRoll(BR, new int[] { 2016, FEBRUARY, 21 }, PM_HOURS);
+
+            testRoll(BR, new int[] { 2016, OCTOBER, 15 }, ALLDAY_HOURS);
+            testRoll(BR, new int[] { 2016, OCTOBER, 15 }, PM_HOURS);
+            testRoll(BR, new int[] { 2016, OCTOBER, 16 },
+                     new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
+                         12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 });
+            testRoll(BR, new int[] { 2016, OCTOBER, 16 },
+                     new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 });
+            testRoll(BR, new int[] { 2016, OCTOBER, 16 }, PM_HOURS);
+        } finally {
+            TimeZone.setDefault(initialTz);
+        }
+        if (errors > 0) {
+            throw new RuntimeException("Test failed");
+        }
+    }
+
+    private static void testRoll(TimeZone tz, int[] params, int[] sequence) {
+        TimeZone.setDefault(tz);
+        for (int i = 0; i < sequence.length; i++) {
+            testRoll(+1, params, sequence, i);
+            testRoll(-1, params, sequence, i);
+        }
+    }
+
+    // amount must be 1 or -1.
+    private static void testRoll(int amount, int[] params, int[] sequence, int startIndex) {
+        int year = params[0];
+        int month = params[1];
+        int dayOfMonth = params[2];
+        int hourOfDay = sequence[startIndex];
+        Calendar cal = new GregorianCalendar(year, month, dayOfMonth,
+                                             hourOfDay, 0, 0);
+        int ampm = cal.get(AM_PM);
+
+        int length = sequence.length;
+        int count = length * 2;
+        int field = (length > 12) ? HOUR_OF_DAY : HOUR;
+
+        System.out.printf("roll(%s, %2d) starting from %s%n",
+                          (field == HOUR) ? "HOUR" : "HOUR_OF_DAY", amount, cal.getTime());
+        for (int i = 0; i < count; i++) {
+            int index = (amount > 0) ? (startIndex + i + 1) % length
+                                     : Math.floorMod(startIndex - i - 1, length);
+            int expected = sequence[index];
+            if (field == HOUR) {
+                expected %= 12;
+            }
+            cal.roll(field, amount);
+            int value = cal.get(field);
+            if (value != expected) {
+                System.out.println("Unexpected field value: got=" + value
+                                    + ", expected=" + expected);
+                errors++;
+            }
+            if (cal.get(DAY_OF_MONTH) != dayOfMonth) {
+                System.out.println("DAY_OF_MONTH changed: " + dayOfMonth
+                                    + " to " + cal.get(DAY_OF_MONTH));
+            }
+            if (field == HOUR && cal.get(AM_PM) != ampm) {
+                System.out.println("AM_PM changed: " + ampm + " to " + cal.get(AM_PM));
+                errors++;
+            }
+        }
+    }
+}