Merge "handle a race condition where a cursor receives an inflight onChange... (2978e5ad) · Commits · e / os / android_frameworks_base

core/java/android/content/ContentQueryMap.java

+17 −9

Original line number	Original line	Diff line number	Diff line
	@@ -33,7 +33,7 @@ import java.util.Observable;
	* The cursor data is accessed by row key and column name via getValue().		* The cursor data is accessed by row key and column name via getValue().
	*/		*/
	public class ContentQueryMap extends Observable {		public class ContentQueryMap extends Observable {
	private Cursor mCursor;		private volatile Cursor mCursor;
	private String[] mColumnNames;		private String[] mColumnNames;
	private int mKeyColumn;		private int mKeyColumn;

	@@ -71,7 +71,7 @@ public class ContentQueryMap extends Observable {
	// ContentProvider then read it once into the cache. Otherwise the cache will be filled		// ContentProvider then read it once into the cache. Otherwise the cache will be filled
	// automatically.		// automatically.
	if (!keepUpdated) {		if (!keepUpdated) {
	readCursorIntoCache();		readCursorIntoCache(cursor);
	}		}
	}		}

	@@ -128,27 +128,35 @@ public class ContentQueryMap extends Observable {

	/** Requeries the cursor and reads the contents into the cache */		/** Requeries the cursor and reads the contents into the cache */
	public void requery() {		public void requery() {
			final Cursor cursor = mCursor;
			if (cursor == null) {
			// If mCursor is null then it means there was a requery() in flight
			// while another thread called close(), which nulls out mCursor.
			// If this happens ignore the requery() since we are closed anyways.
			return;
			}
	mDirty = false;		mDirty = false;
	if (!mCursor.requery()) {		if (!cursor.requery()) {
	throw new IllegalStateException("trying to requery an already closed cursor");		// again, don't do anything if the cursor is already closed
			return;
	}		}
	readCursorIntoCache();		readCursorIntoCache(cursor);
	setChanged();		setChanged();
	notifyObservers();		notifyObservers();
	}		}

	private synchronized void readCursorIntoCache() {		private synchronized void readCursorIntoCache(Cursor cursor) {
	// Make a new map so old values returned by getRows() are undisturbed.		// Make a new map so old values returned by getRows() are undisturbed.
	int capacity = mValues != null ? mValues.size() : 0;		int capacity = mValues != null ? mValues.size() : 0;
	mValues = new HashMap<String, ContentValues>(capacity);		mValues = new HashMap<String, ContentValues>(capacity);
	while (mCursor.moveToNext()) {		while (cursor.moveToNext()) {
	ContentValues values = new ContentValues();		ContentValues values = new ContentValues();
	for (int i = 0; i < mColumnNames.length; i++) {		for (int i = 0; i < mColumnNames.length; i++) {
	if (i != mKeyColumn) {		if (i != mKeyColumn) {
	values.put(mColumnNames[i], mCursor.getString(i));		values.put(mColumnNames[i], cursor.getString(i));
	}		}
	}		}
	mValues.put(mCursor.getString(mKeyColumn), values);		mValues.put(cursor.getString(mKeyColumn), values);
	}		}
	}		}