Stop reading Settings.System.DATE_FORMAT.

Also, move over DateFormat.getInstance(SHORT) instead of
LocaleData.shortDateFormat4 (which forces 4 digit years).
Based on an analysis of git history, there seems to be no
real motiviation for using 4 digit years.

If anyone in the platform complains loudly, we could look at
using a skeleton pattern instead of just replacing 'y' with 'yy'.

If third party apps are affected, we could add a targetSdkversion
based check and revert to the old behaviour for older targetSdks.

bug: 18388178
bug: 18322220
Change-Id: Ieab2b41691958a2e668d382c5a6b3d9aaf741ed2

1 files changed, 10 insertions, 63 deletions

diff --git a/core/java/android/text/format/DateFormat.java b/core/java/android/text/format/DateFormat.java
index d48f551..d515e21 100755
--- a/core/java/android/text/format/DateFormat.java
+++ b/core/java/android/text/format/DateFormat.java
@@ -221,68 +221,13 @@ public class DateFormat {
 
     /**
      * Returns a {@link java.text.DateFormat} object that can format the date
-     * in short form (such as 12/31/1999) according
-     * to the current locale and the user's date-order preference.
+     * in short form according to the current locale.
+     *
      * @param context the application context
      * @return the {@link java.text.DateFormat} object that properly formats the date.
      */
     public static java.text.DateFormat getDateFormat(Context context) {
-        String value = Settings.System.getString(context.getContentResolver(),
-                Settings.System.DATE_FORMAT);
-
-        return getDateFormatForSetting(context, value);
-    }
-
-    /**
-     * Returns a {@link java.text.DateFormat} object to format the date
-     * as if the date format setting were set to <code>value</code>,
-     * including null to use the locale's default format.
-     * @param context the application context
-     * @param value the date format setting string to interpret for
-     *              the current locale
-     * @hide
-     */
-    public static java.text.DateFormat getDateFormatForSetting(Context context,
-                                                               String value) {
-        String format = getDateFormatStringForSetting(context, value);
-        return new java.text.SimpleDateFormat(format);
-    }
-
-    private static String getDateFormatStringForSetting(Context context, String value) {
-        if (value != null) {
-            int month = value.indexOf('M');
-            int day = value.indexOf('d');
-            int year = value.indexOf('y');
-
-            if (month >= 0 && day >= 0 && year >= 0) {
-                String template = context.getString(R.string.numeric_date_template);
-                if (year < month && year < day) {
-                    if (month < day) {
-                        value = String.format(template, "yyyy", "MM", "dd");
-                    } else {
-                        value = String.format(template, "yyyy", "dd", "MM");
-                    }
-                } else if (month < day) {
-                    if (day < year) {
-                        value = String.format(template, "MM", "dd", "yyyy");
-                    } else { // unlikely
-                        value = String.format(template, "MM", "yyyy", "dd");
-                    }
-                } else { // day < month
-                    if (month < year) {
-                        value = String.format(template, "dd", "MM", "yyyy");
-                    } else { // unlikely
-                        value = String.format(template, "dd", "yyyy", "MM");
-                    }
-                }
-
-                return value;
-            }
-        }
-
-        // The setting is not set; use the locale's default.
-        LocaleData d = LocaleData.get(context.getResources().getConfiguration().locale);
-        return d.shortDateFormat4;
+        return java.text.DateFormat.getDateInstance(java.text.DateFormat.SHORT);
     }
 
     /**
@@ -315,14 +260,16 @@ public class DateFormat {
      * order returned here.
      */
     public static char[] getDateFormatOrder(Context context) {
-        return ICU.getDateFormatOrder(getDateFormatString(context));
+        return ICU.getDateFormatOrder(getDateFormatString());
     }
 
-    private static String getDateFormatString(Context context) {
-        String value = Settings.System.getString(context.getContentResolver(),
-                Settings.System.DATE_FORMAT);
+    private static String getDateFormatString() {
+        java.text.DateFormat df = java.text.DateFormat.getDateInstance(java.text.DateFormat.SHORT);
+        if (df instanceof SimpleDateFormat) {
+            return ((SimpleDateFormat) df).toPattern();
+        }
 
-        return getDateFormatStringForSetting(context, value);
+        throw new AssertionError("!(df instanceof SimpleDateFormat)");
     }
 
     /**