Android Cursor Put cursorFillWindow(final Cursor cursor, int position, final CursorWindow window)

Description

Fills the specified cursor window by iterating over the contents of the cursor.

License

Apache License

Parameter

Parameter	Description
cursor	The cursor that contains the data to put in the window.
position	The start position for filling the window.
window	The window to fill.

Declaration

public static void cursorFillWindow(final Cursor cursor, int position,
        final CursorWindow window) 

Method Source Code

//package com.java2s;
//License from project: Apache License 

import android.database.Cursor;
import android.database.CursorWindow;
import android.os.Build;

public class Main {
    /**/*from   w w w  .  ja va2s  . c  o  m*/
     * Fills the specified cursor window by iterating over the contents of the cursor.
     * The window is filled until the cursor is exhausted or the window runs out
     * of space.
     *
     * The original position of the cursor is left unchanged by this operation.
     *
     * @param cursor The cursor that contains the data to put in the window.
     * @param position The start position for filling the window.
     * @param window The window to fill.
     * @hide
     */
    public static void cursorFillWindow(final Cursor cursor, int position,
            final CursorWindow window) {
        if (position < 0 || position >= cursor.getCount()) {
            return;
        }
        final int oldPos = cursor.getPosition();
        final int numColumns = cursor.getColumnCount();
        window.clear();
        window.setStartPosition(position);
        window.setNumColumns(numColumns);
        if (cursor.moveToPosition(position)) {
            do {
                if (!window.allocRow()) {
                    break;
                }
                for (int i = 0; i < numColumns; i++) {
                    boolean success = putToWindow(cursor, i, window,
                            position);
                    if (!success) {
                        window.freeLastRow();
                        break;
                    }
                }
                position += 1;
            } while (cursor.moveToNext());
        }
        cursor.moveToPosition(oldPos);
    }

    /**
     * This method was introduced by AndroidSQLiteServer to work around the lack of
     * {@link Cursor#getType(int)}} on Gingerbread.
     */
    private static boolean putToWindow(Cursor cursor, int column,
            CursorWindow window, int row) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            return putToWindowHoneycombAndBeyond(cursor, column, window,
                    row);
        } else {
            return putToWindowPreHoneycomb(cursor, column, window, row);
        }
    }

    private static boolean putToWindowHoneycombAndBeyond(Cursor cursor,
            int i, CursorWindow window, int position) {
        final int type = cursor.getType(i);
        final boolean success;
        switch (type) {
        case Cursor.FIELD_TYPE_NULL:
            success = window.putNull(position, i);
            break;

        case Cursor.FIELD_TYPE_INTEGER:
            success = window.putLong(cursor.getLong(i), position, i);
            break;

        case Cursor.FIELD_TYPE_FLOAT:
            success = window.putDouble(cursor.getDouble(i), position, i);
            break;

        case Cursor.FIELD_TYPE_BLOB: {
            final byte[] value = cursor.getBlob(i);
            success = value != null ? window.putBlob(value, position, i)
                    : window.putNull(position, i);
            break;
        }

        default: // assume value is convertible to String
        case Cursor.FIELD_TYPE_STRING: {
            final String value = cursor.getString(i);
            success = value != null ? window.putString(value, position, i)
                    : window.putNull(position, i);
            break;
        }
        }

        return success;
    }

    /**
     * This solution is consistent with how Gingerbread implemented
     * {@link android.database.AbstractCursor#fillWindow(int, android.database.CursorWindow)}.
     */
    private static boolean putToWindowPreHoneycomb(Cursor cursor, int i,
            CursorWindow window, int position) {
        String value = cursor.getString(i);
        final boolean success;
        if (value != null) {
            success = window.putString(value, position, i);
        } else {
            success = window.putNull(position, i);
        }
        return success;
    }
}

Related

1. putToWindow(Cursor cursor, int column, CursorWindow window, int row)
2. putToWindowHoneycombAndBeyond(Cursor cursor, int i, CursorWindow window, int position)
3. putToWindowPreHoneycomb(Cursor cursor, int i, CursorWindow window, int position)