Remove time_zones_by_country.xml file

time_zones_by_country.xml has been replaced by a file that can
be updated outside of an OTA and can be accessed via
libcore.util.TimeZoneFinder. This means parsing code has been
removed from this class and replaced by calls to libcore code.

libcore code uses ICU so this class adapts to
java.util.TimeZone for published public APIs as well as other
knock-ons to reduce impact of this change in telephony code.
All use of classes called TimeZone are fully-qualified to
reduce confusion.

Several public-but-hidden methods have been removed. These
can be returned if there are any important apps relying on
them.

Bug: 25338903
Test: Ran CtsUtilTestCases
Change-Id: I699b4e7420e8d7e61ee68ec96552ab3144c9bab2

1 files changed, 54 insertions, 116 deletions

diff --git a/core/java/android/util/TimeUtils.java b/core/java/android/util/TimeUtils.java
index 37d675707a84..2b03ed6c3ae1 100644
--- a/core/java/android/util/TimeUtils.java
+++ b/core/java/android/util/TimeUtils.java
@@ -16,25 +16,17 @@
 
 package android.util;
 
-import android.content.res.Resources;
-import android.content.res.XmlResourceParser;
 import android.os.SystemClock;
-import android.text.format.DateUtils;
 
-import com.android.internal.util.XmlUtils;
-
-import org.xmlpull.v1.XmlPullParser;
-import org.xmlpull.v1.XmlPullParserException;
-
-import java.io.IOException;
 import java.io.PrintWriter;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Calendar;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.Date;
-import java.util.TimeZone;
-
+import java.util.List;
+import libcore.util.TimeZoneFinder;
 import libcore.util.ZoneInfoDB;
 
 /**
@@ -45,14 +37,9 @@ public class TimeUtils {
     private static final boolean DBG = false;
     private static final String TAG = "TimeUtils";
 
-    /** Cached results of getTineZones */
-    private static final Object sLastLockObj = new Object();
-    private static ArrayList<TimeZone> sLastZones = null;
-    private static String sLastCountry = null;
-
     /** Cached results of getTimeZonesWithUniqueOffsets */
     private static final Object sLastUniqueLockObj = new Object();
-    private static ArrayList<TimeZone> sLastUniqueZoneOffsets = null;
+    private static List<String> sLastUniqueZoneOffsets = null;
     private static String sLastUniqueCountry = null;
 
     /** {@hide} */
@@ -63,50 +50,39 @@ public class TimeUtils {
      * and DST value at the specified moment in the specified country.
      * Returns null if no suitable zone could be found.
      */
-    public static TimeZone getTimeZone(int offset, boolean dst, long when, String country) {
-        TimeZone best = null;
-        final Date d = new Date(when);
-
-        TimeZone current = TimeZone.getDefault();
-        String currentName = current.getID();
-        int currentOffset = current.getOffset(when);
-        boolean currentDst = current.inDaylightTime(d);
-
-        for (TimeZone tz : getTimeZones(country)) {
-            // If the current time zone is from the right country
-            // and meets the other known properties, keep it
-            // instead of changing to another one.
-
-            if (tz.getID().equals(currentName)) {
-                if (currentOffset == offset && currentDst == dst) {
-                    return current;
-                }
-            }
+    public static java.util.TimeZone getTimeZone(
+            int offset, boolean dst, long when, String country) {
 
-            // Otherwise, take the first zone from the right
-            // country that has the correct current offset and DST.
-            // (Keep iterating instead of returning in case we
-            // haven't encountered the current time zone yet.)
+        android.icu.util.TimeZone icuTimeZone = getIcuTimeZone(offset, dst, when, country);
+        // We must expose a java.util.TimeZone here for API compatibility because this is a public
+        // API method.
+        return icuTimeZone != null ? java.util.TimeZone.getTimeZone(icuTimeZone.getID()) : null;
+    }
 
-            if (best == null) {
-                if (tz.getOffset(when) == offset &&
-                    tz.inDaylightTime(d) == dst) {
-                    best = tz;
-                }
-            }
+    /**
+     * Tries to return a frozen ICU time zone that would have had the specified offset
+     * and DST value at the specified moment in the specified country.
+     * Returns null if no suitable zone could be found.
+     */
+    private static android.icu.util.TimeZone getIcuTimeZone(
+            int offset, boolean dst, long when, String country) {
+        if (country == null) {
+            return null;
         }
 
-        return best;
+        android.icu.util.TimeZone bias = android.icu.util.TimeZone.getDefault();
+        return TimeZoneFinder.getInstance()
+                .lookupTimeZoneByCountryAndOffset(country, offset, dst, when, bias);
     }
 
     /**
-     * Return list of unique time zones for the country. Do not modify
+     * Returns an immutable list of unique time zone IDs for the country.
      *
      * @param country to find
-     * @return list of unique time zones, maybe empty but never null. Do not modify.
+     * @return unmodifiable list of unique time zones, maybe empty but never null.
      * @hide
      */
-    public static ArrayList<TimeZone> getTimeZonesWithUniqueOffsets(String country) {
+    public static List<String> getTimeZoneIdsWithUniqueOffsets(String country) {
         synchronized(sLastUniqueLockObj) {
             if ((country != null) && country.equals(sLastUniqueCountry)) {
                 if (DBG) {
@@ -117,9 +93,9 @@ public class TimeUtils {
             }
         }
 
-        Collection<TimeZone> zones = getTimeZones(country);
-        ArrayList<TimeZone> uniqueTimeZones = new ArrayList<TimeZone>();
-        for (TimeZone zone : zones) {
+        Collection<android.icu.util.TimeZone> zones = getIcuTimeZones(country);
+        ArrayList<android.icu.util.TimeZone> uniqueTimeZones = new ArrayList<>();
+        for (android.icu.util.TimeZone zone : zones) {
             // See if we already have this offset,
             // Using slow but space efficient and these are small.
             boolean found = false;
@@ -129,7 +105,7 @@ public class TimeUtils {
                     break;
                 }
             }
-            if (found == false) {
+            if (!found) {
                 if (DBG) {
                     Log.d(TAG, "getTimeZonesWithUniqueOffsets: add unique offset=" +
                             zone.getRawOffset() + " zone.getID=" + zone.getID());
@@ -140,81 +116,43 @@ public class TimeUtils {
 
         synchronized(sLastUniqueLockObj) {
             // Cache the last result
-            sLastUniqueZoneOffsets = uniqueTimeZones;
+            sLastUniqueZoneOffsets = extractZoneIds(uniqueTimeZones);
             sLastUniqueCountry = country;
 
             return sLastUniqueZoneOffsets;
         }
     }
 
+    private static List<String> extractZoneIds(List<android.icu.util.TimeZone> timeZones) {
+        List<String> ids = new ArrayList<>(timeZones.size());
+        for (android.icu.util.TimeZone timeZone : timeZones) {
+            ids.add(timeZone.getID());
+        }
+        return Collections.unmodifiableList(ids);
+    }
+
     /**
-     * Returns the time zones for the country, which is the code
-     * attribute of the timezone element in time_zones_by_country.xml. Do not modify.
+     * Returns an immutable list of frozen ICU time zones for the country.
      *
-     * @param country is a two character country code.
-     * @return TimeZone list, maybe empty but never null. Do not modify.
+     * @param countryIso is a two character country code.
+     * @return TimeZone list, maybe empty but never null.
      * @hide
      */
-    public static ArrayList<TimeZone> getTimeZones(String country) {
-        synchronized (sLastLockObj) {
-            if ((country != null) && country.equals(sLastCountry)) {
-                if (DBG) Log.d(TAG, "getTimeZones(" + country + "): return cached version");
-                return sLastZones;
-            }
-        }
-
-        ArrayList<TimeZone> tzs = new ArrayList<TimeZone>();
-
-        if (country == null) {
-            if (DBG) Log.d(TAG, "getTimeZones(null): return empty list");
-            return tzs;
+    private static List<android.icu.util.TimeZone> getIcuTimeZones(String countryIso) {
+        if (countryIso == null) {
+            if (DBG) Log.d(TAG, "getIcuTimeZones(null): return empty list");
+            return Collections.emptyList();
         }
-
-        Resources r = Resources.getSystem();
-        XmlResourceParser parser = r.getXml(com.android.internal.R.xml.time_zones_by_country);
-
-        try {
-            XmlUtils.beginDocument(parser, "timezones");
-
-            while (true) {
-                XmlUtils.nextElement(parser);
-
-                String element = parser.getName();
-                if (element == null || !(element.equals("timezone"))) {
-                    break;
-                }
-
-                String code = parser.getAttributeValue(null, "code");
-
-                if (country.equals(code)) {
-                    if (parser.next() == XmlPullParser.TEXT) {
-                        String zoneIdString = parser.getText();
-                        TimeZone tz = TimeZone.getTimeZone(zoneIdString);
-                        if (tz.getID().startsWith("GMT") == false) {
-                            // tz.getID doesn't start not "GMT" so its valid
-                            tzs.add(tz);
-                            if (DBG) {
-                                Log.d(TAG, "getTimeZone('" + country + "'): found tz.getID=="
-                                    + ((tz != null) ? tz.getID() : "<no tz>"));
-                            }
-                        }
-                    }
-                }
+        List<android.icu.util.TimeZone> timeZones =
+                TimeZoneFinder.getInstance().lookupTimeZonesByCountry(countryIso);
+        if (timeZones == null) {
+            if (DBG) {
+                Log.d(TAG, "getIcuTimeZones(" + countryIso
+                        + "): returned null, converting to empty list");
             }
-        } catch (XmlPullParserException e) {
-            Log.e(TAG, "Got xml parser exception getTimeZone('" + country + "'): e=", e);
-        } catch (IOException e) {
-            Log.e(TAG, "Got IO exception getTimeZone('" + country + "'): e=", e);
-        } finally {
-            parser.close();
-        }
-
-        synchronized(sLastLockObj) {
-            // Cache the last result;
-            sLastZones = tzs;
-            sLastCountry = country;
-            return sLastZones;
+            return Collections.emptyList();
         }
+        return timeZones;
     }
 
     /**