Remove UTC offset from database. Fix clear history.
Bug: 32947084
Also add (currently unused) timestamp index.
The higher level "clear history" code needs work. This seems to work,
but hasn't been thought through very well. It was added mostly so
that I could actually test the ExpressionDB code.
This may require users to clear app data, but I seemed to get away
without it. You may just end up with an extra column if you don't.
Change-Id: Ibd2401a19d73c4824f549befd65a5c63633a894b
diff --git a/src/com/android/calculator2/ExpressionDB.java b/src/com/android/calculator2/ExpressionDB.java
index 0e3a9fa..dc42e1b 100644
--- a/src/com/android/calculator2/ExpressionDB.java
+++ b/src/com/android/calculator2/ExpressionDB.java
@@ -45,8 +45,6 @@
public static final String COLUMN_NAME_FLAGS = "flags";
// Time stamp as returned by currentTimeMillis().
public static final String COLUMN_NAME_TIMESTAMP = "timeStamp";
- // UTC offset at the locale when the expression was saved. In multiples of 15 minutes.
- public static final String COLUMN_NAME_COMPRESSED_UTC_OFFSET = "compressedUtcOffset";
}
/* Data to be written to or read from a row in the table */
@@ -56,7 +54,6 @@
public final byte[] mExpression;
public final int mFlags;
public long mTimeStamp; // 0 ==> this and next field to be filled in when written.
- public byte mCompressedUtcOffset; // multiples of 15 minutes.
private static int flagsFromDegreeAndTimeout(Boolean DegreeMode, Boolean LongTimeout) {
return (DegreeMode ? DEGREE_MODE : 0) | (LongTimeout ? LONG_TIMEOUT : 0);
}
@@ -67,32 +64,18 @@
return (flags & LONG_TIMEOUT) != 0;
}
private static final int MILLIS_IN_15_MINS = 15 * 60 * 1000;
- private static byte compressUtcOffset(int utcOffsetMillis) {
- // Rounded division, though it shouldn't really matter.
- if (utcOffsetMillis > 0) {
- return (byte) ((utcOffsetMillis + MILLIS_IN_15_MINS / 2) / MILLIS_IN_15_MINS);
- } else {
- return (byte) ((utcOffsetMillis - MILLIS_IN_15_MINS / 2) / MILLIS_IN_15_MINS);
- }
- }
- private static int uncompressUtcOffset(byte compressedUtcOffset) {
- return MILLIS_IN_15_MINS * (int)compressedUtcOffset;
- }
- private RowData(byte[] expr, int flags, long timeStamp, byte compressedUtcOffset) {
+ private RowData(byte[] expr, int flags, long timeStamp) {
mExpression = expr;
mFlags = flags;
mTimeStamp = timeStamp;
- mCompressedUtcOffset = compressedUtcOffset;
}
/**
* More client-friendly constructor that hides implementation ugliness.
* utcOffset here is uncompressed, in milliseconds.
* A zero timestamp will cause it to be automatically filled in.
*/
- public RowData(byte[] expr, boolean degreeMode, boolean longTimeout, long timeStamp,
- int utcOffset) {
- this(expr, flagsFromDegreeAndTimeout(degreeMode, longTimeout), timeStamp,
- compressUtcOffset(utcOffset));
+ public RowData(byte[] expr, boolean degreeMode, boolean longTimeout, long timeStamp) {
+ this(expr, flagsFromDegreeAndTimeout(degreeMode, longTimeout), timeStamp);
}
public boolean degreeMode() {
return degreeModeFromFlags(mFlags);
@@ -101,12 +84,6 @@
return longTimeoutFromFlags(mFlags);
}
/**
- * Return UTC offset for timestamp in milliseconds.
- */
- public int utcOffset() {
- return uncompressUtcOffset(mCompressedUtcOffset);
- }
- /**
* Return a ContentValues object representing the current data.
*/
public ContentValues toContentValues() {
@@ -115,11 +92,8 @@
cvs.put(ExpressionEntry.COLUMN_NAME_FLAGS, mFlags);
if (mTimeStamp == 0) {
mTimeStamp = System.currentTimeMillis();
- final TimeZone timeZone = Calendar.getInstance().getTimeZone();
- mCompressedUtcOffset = compressUtcOffset(timeZone.getOffset(mTimeStamp));
}
cvs.put(ExpressionEntry.COLUMN_NAME_TIMESTAMP, mTimeStamp);
- cvs.put(ExpressionEntry.COLUMN_NAME_COMPRESSED_UTC_OFFSET, mCompressedUtcOffset);
return cvs;
}
}
@@ -129,9 +103,8 @@
ExpressionEntry._ID + " INTEGER PRIMARY KEY," +
ExpressionEntry.COLUMN_NAME_EXPRESSION + " BLOB," +
ExpressionEntry.COLUMN_NAME_FLAGS + " INTEGER," +
- ExpressionEntry.COLUMN_NAME_TIMESTAMP + " INTEGER," +
- ExpressionEntry.COLUMN_NAME_COMPRESSED_UTC_OFFSET + " INTEGER)";
- private static final String SQL_DELETE_ENTRIES =
+ ExpressionEntry.COLUMN_NAME_TIMESTAMP + " INTEGER)";
+ private static final String SQL_DROP_TABLE =
"DROP TABLE IF EXISTS " + ExpressionEntry.TABLE_NAME;
private static final String SQL_GET_MIN = "SELECT MIN(" + ExpressionEntry._ID +
") FROM " + ExpressionEntry.TABLE_NAME;
@@ -139,6 +112,11 @@
") FROM " + ExpressionEntry.TABLE_NAME;
private static final String SQL_GET_ROW = "SELECT * FROM " + ExpressionEntry.TABLE_NAME +
" WHERE " + ExpressionEntry._ID + " = ?";
+ // We may eventually need an index by timestamp. We don't use it yet.
+ private static final String SQL_CREATE_TIMESTAMP_INDEX =
+ "CREATE INDEX timestamp_index ON " + ExpressionEntry.TABLE_NAME + "(" +
+ ExpressionEntry.COLUMN_NAME_TIMESTAMP + ")";
+ private static final String SQL_DROP_TIMESTAMP_INDEX = "DROP INDEX IF EXISTS timestamp_index";
private class ExpressionDBHelper extends SQLiteOpenHelper {
// If you change the database schema, you must increment the database version.
@@ -150,10 +128,12 @@
}
public void onCreate(SQLiteDatabase db) {
db.execSQL(SQL_CREATE_ENTRIES);
+ db.execSQL(SQL_CREATE_TIMESTAMP_INDEX);
}
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// For now just throw away history on database version upgrade/downgrade.
- db.execSQL(SQL_DELETE_ENTRIES);
+ db.execSQL(SQL_DROP_TIMESTAMP_INDEX);
+ db.execSQL(SQL_DROP_TABLE);
onCreate(db);
}
public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion) {
@@ -298,33 +278,27 @@
}
}
- public synchronized void eraseAll() {
+ /**
+ * Erase ALL database entries.
+ * This is currently only safe if expressions that may refer to them are also erased.
+ * Should only be called when concurrent references to the database are impossible.
+ * TODO: Look at ways to more selectively clear the database.
+ */
+ public void eraseAll() {
waitForExpressionDB();
- mExpressionDB.execSQL("SQL_DELETE_ENTRIES");
+ mExpressionDB.execSQL(SQL_DROP_TIMESTAMP_INDEX);
+ mExpressionDB.execSQL(SQL_DROP_TABLE);
try {
mExpressionDB.execSQL("VACUUM");
} catch(Exception e) {
Log.v("Calculator", "Database VACUUM failed\n", e);
- // FIXME: probably needed only if there is danger of concurrent execution.
+ // Should only happen with concurrent execution, which should be impossible.
}
- }
-
- /**
- * Update a row in place.
- * Currently unused, since only the main expression is updated in place, and we
- * don't save that in the DB.
- */
- public void updateRow(long index, RowData data) {
- if (index == -1) {
- setBadDB();
- throw new AssertionError("Can't insert row index of -1");
- }
- ContentValues cvs = data.toContentValues();
- cvs.put(ExpressionEntry._ID, index);
- waitForExpressionDB();
- long result = mExpressionDB.replace(ExpressionEntry.TABLE_NAME, null, cvs);
- if (result == -1) {
- throw new AssertionError("Row update failed");
+ mExpressionDB.execSQL(SQL_CREATE_ENTRIES);
+ mExpressionDB.execSQL(SQL_CREATE_TIMESTAMP_INDEX);
+ synchronized(mLock) {
+ mMinIndex = MAXIMUM_MIN_INDEX;
+ mMaxIndex = 0L;
}
}
@@ -368,7 +342,7 @@
throw new AssertionError("Missing Row");
} else {
result = new RowData(resultC.getBlob(1), resultC.getInt(2) /* flags */,
- resultC.getLong(3) /* timestamp */, (byte)resultC.getInt(4) /* UTC offset */);
+ resultC.getLong(3) /* timestamp */);
}
return result;
}