| /* |
| * Copyright (C) 2006 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.content.ContentResolver; |
| import android.net.Uri; |
| import android.os.Bundle; |
| |
| import java.util.Map; |
| |
| /** |
| * This interface provides random read-write access to the result set returned |
| * by a database query. |
| */ |
| public interface Cursor { |
| /** |
| * Returns the numbers of rows in the cursor. |
| * |
| * @return the number of rows in the cursor. |
| */ |
| int getCount(); |
| |
| /** |
| * Returns the current position of the cursor in the row set. |
| * The value is zero-based. When the row set is first returned the cursor |
| * will be at positon -1, which is before the first row. After the |
| * last row is returned another call to next() will leave the cursor past |
| * the last entry, at a position of count(). |
| * |
| * @return the current cursor position. |
| */ |
| int getPosition(); |
| |
| /** |
| * Move the cursor by a relative amount, forward or backward, from the |
| * current position. Positive offsets move forwards, negative offsets move |
| * backwards. If the final position is outside of the bounds of the result |
| * set then the resultant position will be pinned to -1 or count() depending |
| * on whether the value is off the front or end of the set, respectively. |
| * |
| * <p>This method will return true if the requested destination was |
| * reachable, otherwise, it returns false. For example, if the cursor is at |
| * currently on the second entry in the result set and move(-5) is called, |
| * the position will be pinned at -1, and false will be returned. |
| * |
| * @param offset the offset to be applied from the current position. |
| * @return whether the requested move fully succeeded. |
| */ |
| boolean move(int offset); |
| |
| /** |
| * Move the cursor to an absolute position. The valid |
| * range of values is -1 <= position <= count. |
| * |
| * <p>This method will return true if the request destination was reachable, |
| * otherwise, it returns false. |
| * |
| * @param position the zero-based position to move to. |
| * @return whether the requested move fully succeeded. |
| */ |
| boolean moveToPosition(int position); |
| |
| /** |
| * Move the cursor to the first row. |
| * |
| * <p>This method will return false if the cursor is empty. |
| * |
| * @return whether the move succeeded. |
| */ |
| boolean moveToFirst(); |
| |
| /** |
| * Move the cursor to the last row. |
| * |
| * <p>This method will return false if the cursor is empty. |
| * |
| * @return whether the move succeeded. |
| */ |
| boolean moveToLast(); |
| |
| /** |
| * Move the cursor to the next row. |
| * |
| * <p>This method will return false if the cursor is already past the |
| * last entry in the result set. |
| * |
| * @return whether the move succeeded. |
| */ |
| boolean moveToNext(); |
| |
| /** |
| * Move the cursor to the previous row. |
| * |
| * <p>This method will return false if the cursor is already before the |
| * first entry in the result set. |
| * |
| * @return whether the move succeeded. |
| */ |
| boolean moveToPrevious(); |
| |
| /** |
| * Returns whether the cursor is pointing to the first row. |
| * |
| * @return whether the cursor is pointing at the first entry. |
| */ |
| boolean isFirst(); |
| |
| /** |
| * Returns whether the cursor is pointing to the last row. |
| * |
| * @return whether the cursor is pointing at the last entry. |
| */ |
| boolean isLast(); |
| |
| /** |
| * Returns whether the cursor is pointing to the position before the first |
| * row. |
| * |
| * @return whether the cursor is before the first result. |
| */ |
| boolean isBeforeFirst(); |
| |
| /** |
| * Returns whether the cursor is pointing to the position after the last |
| * row. |
| * |
| * @return whether the cursor is after the last result. |
| */ |
| boolean isAfterLast(); |
| |
| /** |
| * Removes the row at the current cursor position from the underlying data |
| * store. After this method returns the cursor will be pointing to the row |
| * after the row that is deleted. This has the side effect of decrementing |
| * the result of count() by one. |
| * <p> |
| * The query must have the row ID column in its selection, otherwise this |
| * call will fail. |
| * |
| * @hide |
| * @return whether the record was successfully deleted. |
| * @deprecated use {@link ContentResolver#delete(Uri, String, String[])} |
| */ |
| @Deprecated |
| boolean deleteRow(); |
| |
| /** |
| * Returns the zero-based index for the given column name, or -1 if the column doesn't exist. |
| * If you expect the column to exist use {@link #getColumnIndexOrThrow(String)} instead, which |
| * will make the error more clear. |
| * |
| * @param columnName the name of the target column. |
| * @return the zero-based column index for the given column name, or -1 if |
| * the column name does not exist. |
| * @see #getColumnIndexOrThrow(String) |
| */ |
| int getColumnIndex(String columnName); |
| |
| /** |
| * Returns the zero-based index for the given column name, or throws |
| * {@link IllegalArgumentException} if the column doesn't exist. If you're not sure if |
| * a column will exist or not use {@link #getColumnIndex(String)} and check for -1, which |
| * is more efficient than catching the exceptions. |
| * |
| * @param columnName the name of the target column. |
| * @return the zero-based column index for the given column name |
| * @see #getColumnIndex(String) |
| * @throws IllegalArgumentException if the column does not exist |
| */ |
| int getColumnIndexOrThrow(String columnName) throws IllegalArgumentException; |
| |
| /** |
| * Returns the column name at the given zero-based column index. |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @return the column name for the given column index. |
| */ |
| String getColumnName(int columnIndex); |
| |
| /** |
| * Returns a string array holding the names of all of the columns in the |
| * result set in the order in which they were listed in the result. |
| * |
| * @return the names of the columns returned in this query. |
| */ |
| String[] getColumnNames(); |
| |
| /** |
| * Return total number of columns |
| * @return number of columns |
| */ |
| int getColumnCount(); |
| |
| /** |
| * Returns the value of the requested column as a byte array. |
| * |
| * <p>If the native content of that column is not blob exception may throw |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @return the value of that column as a byte array. |
| */ |
| byte[] getBlob(int columnIndex); |
| |
| /** |
| * Returns the value of the requested column as a String. |
| * |
| * <p>If the native content of that column is not text the result will be |
| * the result of passing the column value to String.valueOf(x). |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @return the value of that column as a String. |
| */ |
| String getString(int columnIndex); |
| |
| /** |
| * Retrieves the requested column text and stores it in the buffer provided. |
| * If the buffer size is not sufficient, a new char buffer will be allocated |
| * and assigned to CharArrayBuffer.data |
| * @param columnIndex the zero-based index of the target column. |
| * if the target column is null, return buffer |
| * @param buffer the buffer to copy the text into. |
| */ |
| void copyStringToBuffer(int columnIndex, CharArrayBuffer buffer); |
| |
| /** |
| * Returns the value of the requested column as a short. |
| * |
| * <p>If the native content of that column is not numeric the result will be |
| * the result of passing the column value to Short.valueOf(x). |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @return the value of that column as a short. |
| */ |
| short getShort(int columnIndex); |
| |
| /** |
| * Returns the value of the requested column as an int. |
| * |
| * <p>If the native content of that column is not numeric the result will be |
| * the result of passing the column value to Integer.valueOf(x). |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @return the value of that column as an int. |
| */ |
| int getInt(int columnIndex); |
| |
| /** |
| * Returns the value of the requested column as a long. |
| * |
| * <p>If the native content of that column is not numeric the result will be |
| * the result of passing the column value to Long.valueOf(x). |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @return the value of that column as a long. |
| */ |
| long getLong(int columnIndex); |
| |
| /** |
| * Returns the value of the requested column as a float. |
| * |
| * <p>If the native content of that column is not numeric the result will be |
| * the result of passing the column value to Float.valueOf(x). |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @return the value of that column as a float. |
| */ |
| float getFloat(int columnIndex); |
| |
| /** |
| * Returns the value of the requested column as a double. |
| * |
| * <p>If the native content of that column is not numeric the result will be |
| * the result of passing the column value to Double.valueOf(x). |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @return the value of that column as a double. |
| */ |
| double getDouble(int columnIndex); |
| |
| /** |
| * Returns <code>true</code> if the value in the indicated column is null. |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @return whether the column value is null. |
| */ |
| boolean isNull(int columnIndex); |
| |
| /** |
| * Returns <code>true</code> if the cursor supports updates. |
| * |
| * @return whether the cursor supports updates. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean supportsUpdates(); |
| |
| /** |
| * Returns <code>true</code> if there are pending updates that have not yet been committed. |
| * |
| * @return <code>true</code> if there are pending updates that have not yet been committed. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean hasUpdates(); |
| |
| /** |
| * Updates the value for the given column in the row the cursor is |
| * currently pointing at. Updates are not committed to the backing store |
| * until {@link #commitUpdates()} is called. |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @param value the new value. |
| * @return whether the operation succeeded. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean updateBlob(int columnIndex, byte[] value); |
| |
| /** |
| * Updates the value for the given column in the row the cursor is |
| * currently pointing at. Updates are not committed to the backing store |
| * until {@link #commitUpdates()} is called. |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @param value the new value. |
| * @return whether the operation succeeded. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean updateString(int columnIndex, String value); |
| |
| /** |
| * Updates the value for the given column in the row the cursor is |
| * currently pointing at. Updates are not committed to the backing store |
| * until {@link #commitUpdates()} is called. |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @param value the new value. |
| * @return whether the operation succeeded. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean updateShort(int columnIndex, short value); |
| |
| /** |
| * Updates the value for the given column in the row the cursor is |
| * currently pointing at. Updates are not committed to the backing store |
| * until {@link #commitUpdates()} is called. |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @param value the new value. |
| * @return whether the operation succeeded. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean updateInt(int columnIndex, int value); |
| |
| /** |
| * Updates the value for the given column in the row the cursor is |
| * currently pointing at. Updates are not committed to the backing store |
| * until {@link #commitUpdates()} is called. |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @param value the new value. |
| * @return whether the operation succeeded. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean updateLong(int columnIndex, long value); |
| |
| /** |
| * Updates the value for the given column in the row the cursor is |
| * currently pointing at. Updates are not committed to the backing store |
| * until {@link #commitUpdates()} is called. |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @param value the new value. |
| * @return whether the operation succeeded. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean updateFloat(int columnIndex, float value); |
| |
| /** |
| * Updates the value for the given column in the row the cursor is |
| * currently pointing at. Updates are not committed to the backing store |
| * until {@link #commitUpdates()} is called. |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @param value the new value. |
| * @return whether the operation succeeded. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean updateDouble(int columnIndex, double value); |
| |
| /** |
| * Removes the value for the given column in the row the cursor is |
| * currently pointing at. Updates are not committed to the backing store |
| * until {@link #commitUpdates()} is called. |
| * |
| * @param columnIndex the zero-based index of the target column. |
| * @return whether the operation succeeded. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean updateToNull(int columnIndex); |
| |
| /** |
| * Atomically commits all updates to the backing store. After completion, |
| * this method leaves the data in an inconsistent state and you should call |
| * {@link #requery} before reading data from the cursor again. |
| * |
| * @return whether the operation succeeded. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean commitUpdates(); |
| |
| /** |
| * Atomically commits all updates to the backing store, as well as the |
| * updates included in values. After completion, |
| * this method leaves the data in an inconsistent state and you should call |
| * {@link #requery} before reading data from the cursor again. |
| * |
| * @param values A map from row IDs to Maps associating column names with |
| * updated values. A null value indicates the field should be |
| removed. |
| * @return whether the operation succeeded. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| boolean commitUpdates(Map<? extends Long, |
| ? extends Map<String,Object>> values); |
| |
| /** |
| * Reverts all updates made to the cursor since the last call to |
| * commitUpdates. |
| * @hide |
| * @deprecated use the {@link ContentResolver} update methods instead of the Cursor |
| * update methods |
| */ |
| @Deprecated |
| void abortUpdates(); |
| |
| /** |
| * Deactivates the Cursor, making all calls on it fail until {@link #requery} is called. |
| * Inactive Cursors use fewer resources than active Cursors. |
| * Calling {@link #requery} will make the cursor active again. |
| */ |
| void deactivate(); |
| |
| /** |
| * Performs the query that created the cursor again, refreshing its |
| * contents. This may be done at any time, including after a call to {@link |
| * #deactivate}. |
| * |
| * @return true if the requery succeeded, false if not, in which case the |
| * cursor becomes invalid. |
| */ |
| boolean requery(); |
| |
| /** |
| * Closes the Cursor, releasing all of its resources and making it completely invalid. |
| * Unlike {@link #deactivate()} a call to {@link #requery()} will not make the Cursor valid |
| * again. |
| */ |
| void close(); |
| |
| /** |
| * return true if the cursor is closed |
| * @return true if the cursor is closed. |
| */ |
| boolean isClosed(); |
| |
| /** |
| * Register an observer that is called when changes happen to the content backing this cursor. |
| * Typically the data set won't change until {@link #requery()} is called. |
| * |
| * @param observer the object that gets notified when the content backing the cursor changes. |
| * @see #unregisterContentObserver(ContentObserver) |
| */ |
| void registerContentObserver(ContentObserver observer); |
| |
| /** |
| * Unregister an observer that has previously been registered with this |
| * cursor via {@link #registerContentObserver}. |
| * |
| * @param observer the object to unregister. |
| * @see #registerContentObserver(ContentObserver) |
| */ |
| void unregisterContentObserver(ContentObserver observer); |
| |
| /** |
| * Register an observer that is called when changes happen to the contents |
| * of the this cursors data set, for example, when the data set is changed via |
| * {@link #requery()}, {@link #deactivate()}, or {@link #close()}. |
| * |
| * @param observer the object that gets notified when the cursors data set changes. |
| * @see #unregisterDataSetObserver(DataSetObserver) |
| */ |
| void registerDataSetObserver(DataSetObserver observer); |
| |
| /** |
| * Unregister an observer that has previously been registered with this |
| * cursor via {@link #registerContentObserver}. |
| * |
| * @param observer the object to unregister. |
| * @see #registerDataSetObserver(DataSetObserver) |
| */ |
| void unregisterDataSetObserver(DataSetObserver observer); |
| |
| /** |
| * Register to watch a content URI for changes. This can be the URI of a specific data row (for |
| * example, "content://my_provider_type/23"), or a a generic URI for a content type. |
| * |
| * @param cr The content resolver from the caller's context. The listener attached to |
| * this resolver will be notified. |
| * @param uri The content URI to watch. |
| */ |
| void setNotificationUri(ContentResolver cr, Uri uri); |
| |
| /** |
| * onMove() will only be called across processes if this method returns true. |
| * @return whether all cursor movement should result in a call to onMove(). |
| */ |
| boolean getWantsAllOnMoveCalls(); |
| |
| /** |
| * Returns a bundle of extra values. This is an optional way for cursors to provide out-of-band |
| * metadata to their users. One use of this is for reporting on the progress of network requests |
| * that are required to fetch data for the cursor. |
| * |
| * <p>These values may only change when requery is called. |
| * @return cursor-defined values, or Bundle.EMTPY if there are no values. Never null. |
| */ |
| Bundle getExtras(); |
| |
| /** |
| * This is an out-of-band way for the the user of a cursor to communicate with the cursor. The |
| * structure of each bundle is entirely defined by the cursor. |
| * |
| * <p>One use of this is to tell a cursor that it should retry its network request after it |
| * reported an error. |
| * @param extras extra values, or Bundle.EMTPY. Never null. |
| * @return extra values, or Bundle.EMTPY. Never null. |
| */ |
| Bundle respond(Bundle extras); |
| } |