rowdatastatic.java

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/*
      Copyright (C) 2002-2004 MySQL AB

      This program is free software; you can redistribute it and/or modify
      it under the terms of version 2 of the GNU General Public License as 
      published by the Free Software Foundation.

      There are special exceptions to the terms and conditions of the GPL 
      as it is applied to this software. View the full text of the 
      exception in file EXCEPTIONS-CONNECTOR-J in the directory of this 
      software distribution.

      This program 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 for more details.

      You should have received a copy of the GNU General Public License
      along with this program; if not, write to the Free Software
      Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA



 */
package com.mysql.jdbc;

import java.util.ArrayList;
import java.util.List;


/**
 * Represents an in-memory result set
 *
 * @author dgan
 * @version $Id: RowDataStatic.java,v 1.10.4.10 2004/09/18 03:31:18 mmatthew Exp $
 */
public class RowDataStatic implements RowData {
    ResultSet owner;
    private List rows;
    private int index;

    /**
     * Creates a new RowDataStatic object.
     *
     * @param rows DOCUMENT ME!
     */
    public RowDataStatic(ArrayList rows) {
        this.index = -1;
        this.rows = rows;
    }

    /**
     * Returns true if we got the last element.
     *
     * @return DOCUMENT ME!
     */
    public boolean isAfterLast() {
        return this.index >= this.rows.size();
    }

    /**
     * DOCUMENT ME!
     *
     * @param atIndex DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public Object[] getAt(int atIndex) {
        if ((atIndex < 0) || (atIndex >= this.rows.size())) {
            return null;
        }

        return (Object[]) this.rows.get(atIndex);
    }

    /**
     * Returns if iteration has not occured yet.
     *
     * @return DOCUMENT ME!
     */
    public boolean isBeforeFirst() {
        return (this.index == -1) && (this.rows.size() != 0);
    }

    /**
     * DOCUMENT ME!
     *
     * @param newIndex DOCUMENT ME!
     */
    public void setCurrentRow(int newIndex) {
        this.index = newIndex;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public int getCurrentRowNumber() {
        return this.index;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public boolean isDynamic() {
        return false;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public boolean isEmpty() {
        return this.rows.size() == 0;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public boolean isFirst() {
        return this.index == 0;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public boolean isLast() {
        //
        // You can never be on the 'last' row of
        // an empty result set
        //
        if (this.rows.size() == 0) {
            return false;
        }

        return (this.index == (this.rows.size() - 1));
    }

    /**
     * @see com.mysql.jdbc.RowData#setOwner(com.mysql.jdbc.ResultSet)
     */
    public void setOwner(ResultSet rs) {
        this.owner = rs;
    }

    /**
     * @see com.mysql.jdbc.RowData#getOwner()
     */
    public ResultSet getOwner() {
        return this.owner;
    }

    /**
     * DOCUMENT ME!
     *
     * @param row DOCUMENT ME!
     */
    public void addRow(byte[][] row) {
    	this.rows.add(row);
    }

    /**
     * Moves to after last.
     */
    public void afterLast() {
        this.index = this.rows.size();
    }

    /**
     * Moves to before first.
     */
    public void beforeFirst() {
        this.index = -1;
    }

    /**
     * DOCUMENT ME!
     */
    public void beforeLast() {
        this.index = this.rows.size() - 2;
    }

    /**
     * DOCUMENT ME!
     */
    public void close() {
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public boolean hasNext() {
        boolean hasMore = (this.index + 1) < this.rows.size();

        return hasMore;
    }

    /**
     * DOCUMENT ME!
     *
     * @param rows DOCUMENT ME!
     */
    public void moveRowRelative(int rowsToMove) {
        this.index += rowsToMove;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public Object[] next() {
        this.index++;

        if (this.index < this.rows.size()) {
            return (Object[]) this.rows.get(this.index);
        }

        return null;
    }

    /**
     * DOCUMENT ME!
     *
     * @param atIndex DOCUMENT ME!
     */
    public void removeRow(int atIndex) {
    	this.rows.remove(atIndex);
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public int size() {
        return this.rows.size();
    }
}