Straighten out database cursors behavior.

Some were never closed, other closed twice. This change
makes all Cursor instances behave, having the #close()
call in a finally{} clause, and puts the burden of closing
the cursor squarely on the creator rather than in the
called methods.
There is however one exception that is beyond the scope
of this change: UserDictionarySettings have a Cursor
member, it's never closed, and fixing the problem is not
obvious. This change adds a TODO for now.

It's not very clear if this change actually helps with
bug#12670151, but it may be related and it's a good
think to do anyway.

Bug: 12670151
Change-Id: I87cc44387e7dee3da1488671b93a28d9d73f7dc0

1 files changed, 62 insertions, 55 deletions

diff --git a/java/src/com/android/inputmethod/dictionarypack/DictionarySettingsFragment.java b/java/src/com/android/inputmethod/dictionarypack/DictionarySettingsFragment.java
index d18639741..dae2f22a4 100644
--- a/java/src/com/android/inputmethod/dictionarypack/DictionarySettingsFragment.java
+++ b/java/src/com/android/inputmethod/dictionarypack/DictionarySettingsFragment.java
@@ -283,63 +283,70 @@ public final class DictionarySettingsFragment extends PreferenceFragment
             final ArrayList<Preference> result = new ArrayList<Preference>();
             result.add(createErrorMessage(activity, R.string.cannot_connect_to_dict_service));
             return result;
-        } else if (!cursor.moveToFirst()) {
-            final ArrayList<Preference> result = new ArrayList<Preference>();
-            result.add(createErrorMessage(activity, R.string.no_dictionaries_available));
-            cursor.close();
-            return result;
-        } else {
-            final String systemLocaleString = Locale.getDefault().toString();
-            final TreeMap<String, WordListPreference> prefMap =
-                    new TreeMap<String, WordListPreference>();
-            final int idIndex = cursor.getColumnIndex(MetadataDbHelper.WORDLISTID_COLUMN);
-            final int versionIndex = cursor.getColumnIndex(MetadataDbHelper.VERSION_COLUMN);
-            final int localeIndex = cursor.getColumnIndex(MetadataDbHelper.LOCALE_COLUMN);
-            final int descriptionIndex = cursor.getColumnIndex(MetadataDbHelper.DESCRIPTION_COLUMN);
-            final int statusIndex = cursor.getColumnIndex(MetadataDbHelper.STATUS_COLUMN);
-            final int filesizeIndex = cursor.getColumnIndex(MetadataDbHelper.FILESIZE_COLUMN);
-            do {
-                final String wordlistId = cursor.getString(idIndex);
-                final int version = cursor.getInt(versionIndex);
-                final String localeString = cursor.getString(localeIndex);
-                final Locale locale = new Locale(localeString);
-                final String description = cursor.getString(descriptionIndex);
-                final int status = cursor.getInt(statusIndex);
-                final int matchLevel = LocaleUtils.getMatchLevel(systemLocaleString, localeString);
-                final String matchLevelString = LocaleUtils.getMatchLevelSortedString(matchLevel);
-                final int filesize = cursor.getInt(filesizeIndex);
-                // The key is sorted in lexicographic order, according to the match level, then
-                // the description.
-                final String key = matchLevelString + "." + description + "." + wordlistId;
-                final WordListPreference existingPref = prefMap.get(key);
-                if (null == existingPref || existingPref.hasPriorityOver(status)) {
-                    final WordListPreference oldPreference = mCurrentPreferenceMap.get(key);
-                    final WordListPreference pref;
-                    if (null != oldPreference
-                            && oldPreference.mVersion == version
-                            && oldPreference.hasStatus(status)
-                            && oldPreference.mLocale.equals(locale)) {
-                        // If the old preference has all the new attributes, reuse it. Ideally, we
-                        // should reuse the old pref even if its status is different and call
-                        // setStatus here, but setStatus calls Preference#setSummary() which needs
-                        // to be done on the UI thread and we're not on the UI thread here. We
-                        // could do all this work on the UI thread, but in this case it's probably
-                        // lighter to stay on a background thread and throw this old preference out.
-                        pref = oldPreference;
-                    } else {
-                        // Otherwise, discard it and create a new one instead.
-                        // TODO: when the status is different from the old one, we need to
-                        // animate the old one out before animating the new one in.
-                        pref = new WordListPreference(activity, mDictionaryListInterfaceState,
-                                mClientId, wordlistId, version, locale, description, status,
-                                filesize);
+        }
+        try {
+            if (!cursor.moveToFirst()) {
+                final ArrayList<Preference> result = new ArrayList<Preference>();
+                result.add(createErrorMessage(activity, R.string.no_dictionaries_available));
+                return result;
+            } else {
+                final String systemLocaleString = Locale.getDefault().toString();
+                final TreeMap<String, WordListPreference> prefMap =
+                        new TreeMap<String, WordListPreference>();
+                final int idIndex = cursor.getColumnIndex(MetadataDbHelper.WORDLISTID_COLUMN);
+                final int versionIndex = cursor.getColumnIndex(MetadataDbHelper.VERSION_COLUMN);
+                final int localeIndex = cursor.getColumnIndex(MetadataDbHelper.LOCALE_COLUMN);
+                final int descriptionIndex =
+                        cursor.getColumnIndex(MetadataDbHelper.DESCRIPTION_COLUMN);
+                final int statusIndex = cursor.getColumnIndex(MetadataDbHelper.STATUS_COLUMN);
+                final int filesizeIndex = cursor.getColumnIndex(MetadataDbHelper.FILESIZE_COLUMN);
+                do {
+                    final String wordlistId = cursor.getString(idIndex);
+                    final int version = cursor.getInt(versionIndex);
+                    final String localeString = cursor.getString(localeIndex);
+                    final Locale locale = new Locale(localeString);
+                    final String description = cursor.getString(descriptionIndex);
+                    final int status = cursor.getInt(statusIndex);
+                    final int matchLevel =
+                            LocaleUtils.getMatchLevel(systemLocaleString, localeString);
+                    final String matchLevelString =
+                            LocaleUtils.getMatchLevelSortedString(matchLevel);
+                    final int filesize = cursor.getInt(filesizeIndex);
+                    // The key is sorted in lexicographic order, according to the match level, then
+                    // the description.
+                    final String key = matchLevelString + "." + description + "." + wordlistId;
+                    final WordListPreference existingPref = prefMap.get(key);
+                    if (null == existingPref || existingPref.hasPriorityOver(status)) {
+                        final WordListPreference oldPreference = mCurrentPreferenceMap.get(key);
+                        final WordListPreference pref;
+                        if (null != oldPreference
+                                && oldPreference.mVersion == version
+                                && oldPreference.hasStatus(status)
+                                && oldPreference.mLocale.equals(locale)) {
+                            // If the old preference has all the new attributes, reuse it. Ideally,
+                            // we should reuse the old pref even if its status is different and call
+                            // setStatus here, but setStatus calls Preference#setSummary() which
+                            // needs to be done on the UI thread and we're not on the UI thread
+                            // here. We could do all this work on the UI thread, but in this case
+                            // it's probably lighter to stay on a background thread and throw this
+                            // old preference out.
+                            pref = oldPreference;
+                        } else {
+                            // Otherwise, discard it and create a new one instead.
+                            // TODO: when the status is different from the old one, we need to
+                            // animate the old one out before animating the new one in.
+                            pref = new WordListPreference(activity, mDictionaryListInterfaceState,
+                                    mClientId, wordlistId, version, locale, description, status,
+                                    filesize);
+                        }
+                        prefMap.put(key, pref);
                     }
-                    prefMap.put(key, pref);
-                }
-            } while (cursor.moveToNext());
+                } while (cursor.moveToNext());
+                mCurrentPreferenceMap = prefMap;
+                return prefMap.values();
+            }
+        } finally {
             cursor.close();
-            mCurrentPreferenceMap = prefMap;
-            return prefMap.values();
         }
     }