Merge "Add a CrossProcessCursorWrapper. Bug: 5220669" (aac01f69) · Commits · e / os / android_frameworks_base

api/current.txt

+7 −0

Original line number	Diff line number	Diff line
		@@ -6782,6 +6782,13 @@ package android.database {
		method public abstract boolean onMove(int, int);
		}

		public class CrossProcessCursorWrapper extends android.database.CursorWrapper implements android.database.CrossProcessCursor {
		ctor public CrossProcessCursorWrapper(android.database.Cursor);
		method public void fillWindow(int, android.database.CursorWindow);
		method public android.database.CursorWindow getWindow();
		method public boolean onMove(int, int);
		}

		public abstract interface Cursor {
		method public abstract void close();
		method public abstract void copyStringToBuffer(int, android.database.CharArrayBuffer);

core/java/android/content/ContentResolver.java

+2 −1

Original line number	Diff line number	Diff line
		@@ -26,6 +26,7 @@ import android.content.pm.PackageManager.NameNotFoundException;
		import android.content.res.AssetFileDescriptor;
		import android.content.res.Resources;
		import android.database.ContentObserver;
		import android.database.CrossProcessCursorWrapper;
		import android.database.Cursor;
		import android.database.CursorWrapper;
		import android.database.IContentObserver;
		@@ -1568,7 +1569,7 @@ public abstract class ContentResolver {
		samplePercent);
		}

		private final class CursorWrapperInner extends CursorWrapper {
		private final class CursorWrapperInner extends CrossProcessCursorWrapper {
		private final IContentProvider mContentProvider;
		public static final String TAG="CursorWrapperInner";

core/java/android/database/CrossProcessCursor.java

+44 −8

Original line number	Diff line number	Diff line
		@@ -16,27 +16,63 @@

		package android.database;

		/**
		* A cross process cursor is an extension of a {@link Cursor} that also supports
		* usage from remote processes.
		* <p>
		* The contents of a cross process cursor are marshalled to the remote process by
		* filling {@link CursorWindow} objects using {@link #fillWindow}. As an optimization,
		* the cursor can provide a pre-filled window to use via {@link #getWindow} thereby
		* obviating the need to copy the data to yet another cursor window.
		*/
		public interface CrossProcessCursor extends Cursor {
		/**
		* returns a pre-filled window, return NULL if no such window
		* Returns a pre-filled window that contains the data within this cursor.
		* <p>
		* In particular, the window contains the row indicated by {@link Cursor#getPosition}.
		* The window's contents are automatically scrolled whenever the current
		* row moved outside the range covered by the window.
		* </p>
		*
		* @return The pre-filled window, or null if none.
		*/
		CursorWindow getWindow();

		/**
		* copies cursor data into the window start at pos
		* Copies cursor data into the window.
		* <p>
		* Clears the window and fills it with data beginning at the requested
		* row position until all of the data in the cursor is exhausted
		* or the window runs out of space.
		* </p><p>
		* The filled window uses the same row indices as the original cursor.
		* For example, if you fill a window starting from row 5 from the cursor,
		* you can query the contents of row 5 from the window just by asking it
		* for row 5 because there is a direct correspondence between the row indices
		* used by the cursor and the window.
		* </p><p>
		* The current position of the cursor, as returned by {@link #getPosition},
		* is not changed by this method.
		* </p>
		*
		* @param position The zero-based index of the first row to copy into the window.
		* @param window The window to fill.
		*/
		void fillWindow(int pos, CursorWindow winow);
		void fillWindow(int position, CursorWindow window);

		/**
		* This function is called every time the cursor is successfully scrolled
		* to a new position, giving the subclass a chance to update any state it
		* may have. If it returns false the move function will also do so and the
		* cursor will scroll to the beforeFirst position.
		* <p>
		* This function should be called by methods such as {@link #moveToPosition(int)},
		* so it will typically not be called from outside of the cursor class itself.
		* </p>
		*
		* @param oldPosition the position that we're moving from
		* @param newPosition the position that we're moving to
		* @return true if the move is successful, false otherwise
		* @param oldPosition The position that we're moving from.
		* @param newPosition The position that we're moving to.
		* @return True if the move is successful, false otherwise.
		*/
		boolean onMove(int oldPosition, int newPosition);

		}

core/java/android/database/CrossProcessCursorWrapper.java

0 → 100644

+75 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2011 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License
		*/

		package android.database;

		import android.database.CrossProcessCursor;
		import android.database.Cursor;
		import android.database.CursorWindow;
		import android.database.CursorWrapper;

		/**
		* Cursor wrapper that implements {@link CrossProcessCursor}.
		* <p>
		* If the wrapper cursor implemented {@link CrossProcessCursor}, then delegates
		* {@link #fillWindow}, {@link #getWindow()} and {@link #onMove} to it. Otherwise,
		* provides default implementations of these methods that traverse the contents
		* of the cursor similar to {@link AbstractCursor#fillWindow}.
		* </p><p>
		* This wrapper can be used to adapt an ordinary {@link Cursor} into a
		* {@link CrossProcessCursor}.
		* </p>
		*/
		public class CrossProcessCursorWrapper extends CursorWrapper implements CrossProcessCursor {
		/**
		* Creates a cross process cursor wrapper.
		* @param cursor The underlying cursor to wrap.
		*/
		public CrossProcessCursorWrapper(Cursor cursor) {
		super(cursor);
		}

		@Override
		public void fillWindow(int position, CursorWindow window) {
		if (mCursor instanceof CrossProcessCursor) {
		final CrossProcessCursor crossProcessCursor = (CrossProcessCursor)mCursor;
		crossProcessCursor.fillWindow(position, window);
		return;
		}

		DatabaseUtils.cursorFillWindow(mCursor, position, window);
		}

		@Override
		public CursorWindow getWindow() {
		if (mCursor instanceof CrossProcessCursor) {
		final CrossProcessCursor crossProcessCursor = (CrossProcessCursor)mCursor;
		return crossProcessCursor.getWindow();
		}

		return null;
		}

		@Override
		public boolean onMove(int oldPosition, int newPosition) {
		if (mCursor instanceof CrossProcessCursor) {
		final CrossProcessCursor crossProcessCursor = (CrossProcessCursor)mCursor;
		return crossProcessCursor.onMove(oldPosition, newPosition);
		}

		return true;
		}
		}

core/java/android/database/CursorToBulkCursorAdaptor.java

+4 −5

Original line number	Diff line number	Diff line
		@@ -89,11 +89,10 @@ public final class CursorToBulkCursorAdaptor extends BulkCursorNative

		public CursorToBulkCursorAdaptor(Cursor cursor, IContentObserver observer,
		String providerName) {
		try {
		if (cursor instanceof CrossProcessCursor) {
		mCursor = (CrossProcessCursor)cursor;
		} catch (ClassCastException e) {
		throw new UnsupportedOperationException(
		"Only CrossProcessCursor cursors are supported across process for now", e);
		} else {
		mCursor = new CrossProcessCursorWrapper(cursor);
		}
		mProviderName = providerName;