rowdatastatic.java

一个网上书店程序!实现网上购书结算等！ 由jsp+javabean+mysql组成！ 功能很完善

/*
   Copyright (C) 2002 MySQL AB

      This program is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published by
      the Free Software Foundation; either version 2 of the License, or
      (at your option) any later version.

      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 1.10.2.3 2003/10/03 16:29:44 mmatthew Exp $
 */
public class RowDataStatic implements RowData {
    private List rows;
    private int index;
    private ResultSet owner;

    /**
     * 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 >= rows.size();
    }

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

	/**
	 * @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!
     *
     * @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 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 (rows.size() == 0) {
            return false;
        }

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

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

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

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

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

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

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

        return hasMore;
    }

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

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

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

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

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