commit ec727411d2d97ba79d3e32edb304279af078377e
author Eino-Ville Talvala <etalvala@google.com> Tue Sep 27 17:15:11 2016 -0700
committer Eino-Ville Talvala <etalvala@google.com> Wed Sep 28 11:10:00 2016 -0700
tree 810a930440da1463ac4feba8a65dc5116687e334
parent 29678c0357b5803ae41ad10639da5656d3c285d5

DngCreator: Do not cache timezone in static initializer

The static initializer for a pre-loaded framework class is run
no later than at zygote startup, which happens at device boot.

Which means that if the timezone later changes, DngCreator will use
an incorrect cached timezone until the next reboot.  This is especially
evident in freshly wiped devices, where initial setup will typically
change the timezone.

Instead, read the timezone each time DngCreator is created, which is
also when we query the current time for constructing the timestamps.

Test: android.hardware.camera2.cts.DngCreatorTest#testSingleImageThumbnail
Bug: 31743060
Change-Id: I83a4eac762650e5f904f3b8fa779c094cef30562

core/java/android/hardware/camera2/DngCreator.java

diff --git a/core/java/android/hardware/camera2/DngCreator.java b/core/java/android/hardware/camera2/DngCreator.java
index 45fa15e..1a51acd 100644
--- a/core/java/android/hardware/camera2/DngCreator.java
+++ b/core/java/android/hardware/camera2/DngCreator.java
@@ -119,8 +119,14 @@
             captureTime = timestamp / 1000000 + timeOffset;
         }
 
+        // Create this fresh each time since the time zone may change while a long-running application
+        // is active.
+        final DateFormat dateTimeStampFormat =
+            new SimpleDateFormat(TIFF_DATETIME_FORMAT);
+        dateTimeStampFormat.setTimeZone(TimeZone.getDefault());
+
         // Format for metadata
-        String formattedCaptureTime = sDateTimeStampFormat.format(captureTime);
+        String formattedCaptureTime = dateTimeStampFormat.format(captureTime);
 
         nativeInit(characteristics.getNativeCopy(), metadata.getNativeCopy(),
                 formattedCaptureTime);
@@ -467,13 +473,10 @@
     private static final String GPS_DATE_FORMAT_STR = "yyyy:MM:dd";
     private static final String TIFF_DATETIME_FORMAT = "yyyy:MM:dd HH:mm:ss";
     private static final DateFormat sExifGPSDateStamp = new SimpleDateFormat(GPS_DATE_FORMAT_STR);
-    private static final DateFormat sDateTimeStampFormat =
-            new SimpleDateFormat(TIFF_DATETIME_FORMAT);
     private final Calendar mGPSTimeStampCalendar = Calendar
             .getInstance(TimeZone.getTimeZone("UTC"));
 
     static {
-        sDateTimeStampFormat.setTimeZone(TimeZone.getDefault());
         sExifGPSDateStamp.setTimeZone(TimeZone.getTimeZone("UTC"));
     }