19066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project/* 29066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Copyright (C) 2008 The Android Open Source Project 39066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 49066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Licensed under the Apache License, Version 2.0 (the "License"); 59066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * you may not use this file except in compliance with the License. 69066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * You may obtain a copy of the License at 79066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 89066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * http://www.apache.org/licenses/LICENSE-2.0 99066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 109066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Unless required by applicable law or agreed to in writing, software 119066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * distributed under the License is distributed on an "AS IS" BASIS, 129066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 139066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * See the License for the specific language governing permissions and 149066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * limitations under the License. 159066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 169066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 179066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectpackage android.database; 189066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 19825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown/** 20825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * A cross process cursor is an extension of a {@link Cursor} that also supports 21825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * usage from remote processes. 22825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * <p> 23825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * The contents of a cross process cursor are marshalled to the remote process by 24825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * filling {@link CursorWindow} objects using {@link #fillWindow}. As an optimization, 25825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * the cursor can provide a pre-filled window to use via {@link #getWindow} thereby 26825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * obviating the need to copy the data to yet another cursor window. 27825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown */ 28d2183654e03d589b120467f4e98da1b178ceeadbJeff Brownpublic interface CrossProcessCursor extends Cursor { 299066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 30825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * Returns a pre-filled window that contains the data within this cursor. 31825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * <p> 32825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * In particular, the window contains the row indicated by {@link Cursor#getPosition}. 33825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * The window's contents are automatically scrolled whenever the current 34825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * row moved outside the range covered by the window. 35825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * </p> 36825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * 37825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * @return The pre-filled window, or null if none. 389066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 399066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project CursorWindow getWindow(); 409066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 419066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 42825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * Copies cursor data into the window. 43825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * <p> 44825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * Clears the window and fills it with data beginning at the requested 45825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * row position until all of the data in the cursor is exhausted 46825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * or the window runs out of space. 47825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * </p><p> 48825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * The filled window uses the same row indices as the original cursor. 49825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * For example, if you fill a window starting from row 5 from the cursor, 50825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * you can query the contents of row 5 from the window just by asking it 51825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * for row 5 because there is a direct correspondence between the row indices 52825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * used by the cursor and the window. 53825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * </p><p> 54825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * The current position of the cursor, as returned by {@link #getPosition}, 55825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * is not changed by this method. 56825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * </p> 57825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * 58825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * @param position The zero-based index of the first row to copy into the window. 59825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * @param window The window to fill. 609066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 61825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown void fillWindow(int position, CursorWindow window); 629066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 639066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 649066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * This function is called every time the cursor is successfully scrolled 659066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * to a new position, giving the subclass a chance to update any state it 66825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * may have. If it returns false the move function will also do so and the 679066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * cursor will scroll to the beforeFirst position. 68825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * <p> 69825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * This function should be called by methods such as {@link #moveToPosition(int)}, 70825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * so it will typically not be called from outside of the cursor class itself. 71825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * </p> 729066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 73825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * @param oldPosition The position that we're moving from. 74825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * @param newPosition The position that we're moving to. 75825c5132bff21e72c1448241f4c6868563c8d624Jeff Brown * @return True if the move is successful, false otherwise. 769066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 779066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project boolean onMove(int oldPosition, int newPosition); 789066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project} 79