java分页类

package Servlet;


import java.util.*;

/**
* <p>Title: PageResultSet</p>
*
* <p>Description:分页类 </p>
*
* <p>Copyright: Copyright (c) 2004</p>
*
* <p>Company:youngor-studio(http://www.54youngor.com) </p>
* @author:伍维波
* @version 1.0
*/
public class PageResultSet {
    /**
     * 分页数据
     */
    private List data = null;
    /**
     * 当前页
     */
    private static int curPage;
    /**
     * 每页显示的记录数
     */
    private static int pageSize;
    /**
     * 记录行数
     */
    private static int rowsCount;
    /**
     * 页数
     */
    private static int pageCount;

    public PageResultSet(List data) {
        this.data = data;
        this.curPage = 1;
        this.pageSize = 10;
        this.rowsCount = data.size();
        this.pageCount = (int) Math.ceil((double) rowsCount / pageSize);
    }

    public PageResultSet(List data, int curPage) {
        this.data = data;
        this.curPage = curPage;
        this.pageSize = 10;
        this.rowsCount = data.size();
        this.pageCount = (int) Math.ceil((double) rowsCount / pageSize);
    }

    public PageResultSet(List data, int curPage, int pageSize) {
        this.data = data;
        this.curPage = curPage;
        this.pageSize = pageSize;
        this.rowsCount = data.size();
        this.pageCount = (int) Math.ceil((double) rowsCount / pageSize);
    }

    /**
     * getCurPage:返回当前的页数
     *
     * @return int
     */
    public int getCurPage() {
        return curPage;
    }

    /**
     * getPageSize：返回分页大小
     *
     * @return int
     */
    public int getPageSize() {
        return pageSize;
    }

    /**
     * getRowsCount：返回总记录行数
     *
     * @return int
     */
    public int getRowsCount() {
        return rowsCount;
    }

    /**
     * getPageCount：返回总页数
     *
     * @return int
     */
    public int getPageCount() {
        return pageCount;
    }
    /**
     * 第一页
     * @return int
     */
    public int first() {
        return 1;
    }
    /**
     * 最后一页
     * @return int
     */
    public int last() {
        return pageCount;
    }
    /**
     * 上一页
     * @return int
     */
    public int previous() {
        return (curPage - 1 < 1) ? 1 : curPage - 1;
    }
    /**
     * 下一页
     * @return int
     */
    public int next() {
        return (curPage + 1 > pageCount) ? pageCount : curPage + 1;
    }

    /**
     * 第一页
     * @return boolean
     */
    public boolean isFirst() {
        return (curPage==1)?true:false;
    }

    /**
     * 第一页
     * @return boolean
     */
    public boolean isLast() {
        return (curPage==pageCount)?true:false;
    }
    /**
     * 获取当前页数据
     * @return Collection
     */
    public List getData() {
    List curData = null;
        if (data != null) {
            int start = (curPage - 1) * pageSize;
            int end = 0;
            if (start + pageSize > rowsCount)
                end = rowsCount;
            else
                end = start + pageSize;
            ArrayList arrayCurData = new ArrayList();
            ArrayList arrayData = null;
            Vector vectorCurData = new Vector();
            Vector vectorData = null;
            boolean isArray = true;
            if (data instanceof ArrayList) {
                arrayData = (ArrayList) data;
                isArray = true;
            } else if (data instanceof Vector) {
                vectorData = (Vector) data;
                isArray = false;
            }
            for (int i = start; i < end; i++) {
                if (isArray) {
                    arrayCurData.add(arrayData.get(i));
                } else {
                    vectorData.add(vectorData.elementAt(i));
                }
            }
            if (isArray) {
                curData = (List) arrayCurData;
            } else {
                curData = (List) vectorCurData;
            }
        }
        return curData;
    }
    /**
     * 获取工具条
     * @return String
     */
    public String getToolBar(String fileName){
        String temp="";
        if(fileName.indexOf("?")==-1)
        {
            temp="?";
        }
        else
        {
            temp="&";
        }
        String str="<form method='post' action='"+fileName+"'>";
        str+="<p align='center'>";
        if(isFirst())
            str+="首页 上一页&nbsp;";
        else
        {
            str+="<a href='"+fileName+temp+"cur_page=1'>首页</a>&nbsp;";
            str+="<a href='"+fileName+temp+"cur_page="+(curPage-1)+"'>上一页</a>&nbsp;";
        }
        if(isLast())
            str+="下一页 尾页&nbsp;";
        else
        {
            str+="<a href='"+fileName+temp+"cur_page="+(curPage+1)+"'>下一页</a>&nbsp;";
            str+="<a href='"+fileName+temp+"cur_page="+pageCount+"'>尾页</a>&nbsp;";
        }
        str+="&nbsp;共<b>"+rowsCount+"</b>条记录&nbsp;";
        str+="&nbsp;转到<select location='"+fileName+temp+"cur_page='+this.options[this.selectedIndex].value\">";
        for(int i=1;i<=pageCount;i++)
        {
            if(i==curPage)
                str+="<option value='"+i+"' selected>第"+i+"页</option>";
            else
                str+="<option value='"+i+"'>第"+i+"页</option>";
        }
        str+="</select></p></form>";
        return str;
    }
}