/*

 * Copyright 2003-2006 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package com.sun.rowset.internal;

import java.sql.*;

import java.io.*;

import java.math.*;

import java.lang.*;

import java.lang.reflect.*;

import java.util.*;

/**

 * A class that keeps track of a row's values. A <code>Row</code> object

 * maintains an array of current column values and an array of original

 * column values, and it provides methods for getting and setting the

 * value of a column.  It also keeps track of which columns have

 * changed and whether the change was a delete, insert, or update.

 * <P>

 * Note that column numbers for rowsets start at <code>1</code>,

 * whereas the first element of an array or bitset is <code>0</code>.

 * The argument for the method <code>getColumnUpdated</code> refers to

 * the column number in the rowset (the first column is <code>1</code>);

 * the argument for <code>setColumnUpdated</code> refers to the index

 * into the rowset's internal bitset (the first bit is <code>0</code>).

 */

public class Row extends BaseRow implements Serializable, Cloneable {

/**

 * An array containing the current column values for this <code>Row</code>

 * object.

 * @serial

 */

    private Object[] currentVals;

/**

 * A <code>BitSet</code> object containing a flag for each column in

 * this <code>Row</code> object, with each flag indicating whether or

 * not the value in the column has been changed.

 * @serial

 */

    private BitSet colsChanged;

/**

 * A <code>boolean</code> indicating whether or not this <code>Row</code>

 * object has been deleted.  <code>true</code> indicates that it has

 * been deleted; <code>false</code> indicates that it has not.

 * @serial

 */

    private boolean deleted;

/**

 * A <code>boolean</code> indicating whether or not this <code>Row</code>

 * object has been updated.  <code>true</code> indicates that it has

 * been updated; <code>false</code> indicates that it has not.

 * @serial

 */

    private boolean updated;

/**

 * A <code>boolean</code> indicating whether or not this <code>Row</code>

 * object has been inserted.  <code>true</code> indicates that it has

 * been inserted; <code>false</code> indicates that it has not.

 * @serial

 */

    private boolean inserted;

/**

 * The number of columns in this <code>Row</code> object.

 * @serial

 */

    private int numCols;

/**

 * Creates a new <code>Row</code> object with the given number of columns.

 * The newly-created row includes an array of original values,

 * an array for storing its current values, and a <code>BitSet</code>

 * object for keeping track of which column values have been changed.

 */

    public Row(int numCols) {

        origVals = new Object[numCols];

        currentVals = new Object[numCols];

        colsChanged = new BitSet(numCols);

        this.numCols = numCols;

    }

/**

 * Creates a new <code>Row</code> object with the given number of columns

 * and with its array of original values initialized to the given array.

 * The new <code>Row</code> object also has an array for storing its

 * current values and a <code>BitSet</code> object for keeping track

 * of which column values have been changed.

 */

    public Row(int numCols, Object[] vals) {

        origVals = new Object[numCols];

        for (int i=0; i < numCols; i++) {

            origVals[i] = vals[i];

        }

        currentVals = new Object[numCols];

        colsChanged = new BitSet(numCols);

        this.numCols = numCols;

    }

/**

 *

 * This method is called internally by the <code>CachedRowSet.populate</code>

 * methods.

 *

 * @param idx the number of the column in this <code>Row</code> object

 *            that is to be set; the index of the first column is

 *            <code>1</code>

 * @param val the new value to be set

 */

    public void initColumnObject(int idx, Object val) {

        origVals[idx - 1] = val;

    }

/**

 *

 * This method is called internally by the <code>CachedRowSet.updateXXX</code>

 * methods.

 *

 * @param idx the number of the column in this <code>Row</code> object

 *            that is to be set; the index of the first column is

 *            <code>1</code>

 * @param val the new value to be set

 */

    public void setColumnObject(int idx, Object val) {

            currentVals[idx - 1] = val;

            setColUpdated(idx - 1);

    }

/**

 * Retrieves the column value stored in the designated column of this

 * <code>Row</code> object.

 *

 * @param columnIndex the index of the column value to be retrieved;

 *                    the index of the first column is <code>1</code>

 * @return an <code>Object</code> in the Java programming language that

 *         represents the value stored in the designated column

 * @throws SQLException if there is a database access error

 */

    public Object getColumnObject(int columnIndex) throws SQLException {

        if (getColUpdated(columnIndex - 1)) {

            return(currentVals[columnIndex - 1]); // maps to array!!

        } else {

            return(origVals[columnIndex - 1]); // maps to array!!

        }

    }

/**

 * Indicates whether the designated column of this <code>Row</code> object

 * has been changed.

 * @param idx the index into the <code>BitSet</code> object maintained by

 *            this <code>Row</code> object to keep track of which column

 *            values have been modified; the index of the first bit is

 *            <code>0</code>

 * @return <code>true</code> if the designated column value has been changed;

 *         <code>false</code> otherwise

 *

 */

    public boolean getColUpdated(int idx) {

        return colsChanged.get(idx);

    }

/**

 * Sets this <code>Row</code> object's <code>deleted</code> field

 * to <code>true</code>.

 *

 * @see #getDeleted

 */

    public void setDeleted() { // %%% was public

        deleted = true;

    }

/**

 * Retrieves the value of this <code>Row</code> object's <code>deleted</code> field,

 * which will be <code>true</code> if one or more of its columns has been

 * deleted.

 * @return <code>true</code> if a column value has been deleted; <code>false</code>

 *         otherwise

 *

 * @see #setDeleted

 */

    public boolean getDeleted() {

        return(deleted);

    }

/**

 * Sets the <code>deleted</code> field for this <code>Row</code> object to

 * <code>false</code>.

 */

    public void clearDeleted() {

        deleted = false;

    }

/**

 * Sets the value of this <code>Row</code> object's <code>inserted</code> field

 * to <code>true</code>.

 *

 * @see #getInserted

 */

    public void setInserted() {

        inserted = true;

    }

/**

 * Retrieves the value of this <code>Row</code> object's <code>inserted</code> field,

 * which will be <code>true</code> if this row has been inserted.

 * @return <code>true</code> if this row has been inserted; <code>false</code>

 *         otherwise

 *

 * @see #setInserted

 */

    public boolean getInserted() {

        return(inserted);

    }

/**

 * Sets the <code>inserted</code> field for this <code>Row</code> object to

 * <code>false</code>.

 */

    public void clearInserted() { // %%% was public

        inserted = false;

    }

/**

 * Retrieves the value of this <code>Row</code> object's

 * <code>updated</code> field.

 * @return <code>true</code> if this <code>Row</code> object has been

 *         updated; <code>false</code> if it has not

 *

 * @see #setUpdated

 */

    public boolean getUpdated() {

        return(updated);

    }

/**

 * Sets the <code>updated</code> field for this <code>Row</code> object to

 * <code>true</code> if one or more of its column values has been changed.

 *

 * @see #getUpdated

 */

    public void setUpdated() {

        // only mark something as updated if one or

        // more of the columns has been changed.

        for (int i = 0; i < numCols; i++) {

            if (getColUpdated(i) == true) {

                updated = true;

                return;

            }

        }

    }

/**

 * Sets the bit at the given index into this <code>Row</code> object's internal

 * <code>BitSet</code> object, indicating that the corresponding column value

 * (column <code>idx</code> + 1) has been changed.

 *

 * @param idx the index into the <code>BitSet</code> object maintained by

 *            this <code>Row</code> object; the first bit is at index

 *            <code>0</code>

 *

 */

    private void setColUpdated(int idx) {

        colsChanged.set(idx);

    }

/**

 * Sets the <code>updated</code> field for this <code>Row</code> object to

 * <code>false</code>, sets all the column values in this <code>Row</code>

 * object's internal array of current values to <code>null</code>, and clears

 * all of the bits in the <code>BitSet</code> object maintained by this

 * <code>Row</code> object.

 */

    public void clearUpdated() {

        updated = false;

        for (int i = 0; i < numCols; i++) {

            currentVals[i] = null;

            colsChanged.clear(i);

        }

    }

   /**

    * Sets the column values in this <code>Row</code> object's internal

    * array of original values with the values in its internal array of

    * current values, sets all the values in this <code>Row</code>

    * object's internal array of current values to <code>null</code>,

    * clears all the bits in this <code>Row</code> object's internal bitset,

    * and sets its <code>updated</code> field to <code>false</code>.

    * <P>

    * This method is called internally by the <code>CachedRowSet</code>

    * method <code>makeRowOriginal</code>.

    */

    public void moveCurrentToOrig() {

        for (int i = 0; i < numCols; i++) {

            if (getColUpdated(i) == true) {

                origVals[i] = currentVals[i];

                currentVals[i] = null;

                colsChanged.clear(i);

            }

        }

        updated = false;

    }

   /**

    * Returns the row on which the cursor is positioned.

    *

    * @return the <code>Row</code> object on which the <code>CachedRowSet</code>

    *           implementation objects's cursor is positioned

    */

    public BaseRow getCurrentRow() {

        return null;

    }

}