一个简单的翻页代码

<%...@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %>
<%...
    String currentPage=request.getParameter("currentPage");
    String pages=request.getParameter("pages");
%>
<div id="show">&nbsp;</div>
<script>...
    var currentPage=<%=currentPage%>;
    var pages=<%=pages%>;
    var group;
    if(currentPage%10==0)...{
        group=Math.floor(currentPage/10);
    }else...{
        group=Math.floor(currentPage/10+1);
    }
    

    function showPage(currentGroup)...{
        var showStr="";
        var groups;
        if(pages%10==0)...{
            groups=Math.floor(pages/10);
        }else...{
            groups=Math.floor(pages/10+1);
        }
        //向前滚动
        if(currentGroup<=1)...{
            showStr=showStr+"<<";
        }else...{
            showStr=showStr+"<a href='javascript:showPage("+(currentGroup-1)+")'><<</a>";
        }

        if(pages<=10)...{
            for(var i=1;i<=pages;i++)...{
                if(i==currentPage)...{
                    showStr=showStr+"&nbsp;[<a href='a.jsp?currentPage="+i+"&pages=<%=pages%>'>"+i+"</a>]&nbsp;";
                }else...{
                    showStr=showStr+"&nbsp;<a href='a.jsp?currentPage="+i+"&pages=<%=pages%>'>"+i+"</a>&nbsp;";
                }
            }
        }else if((pages-currentPage)<=pages%10 || (currentGroup==groups && pages%10!=0))...{
            var num;
            for(var i=1;i<=pages%10;i++)...{
                num=(currentGroup-1)*10+i;
                if(num==currentPage)...{
                    showStr=showStr+"&nbsp;[<a href='a.jsp?currentPage="+num+"&pages=<%=pages%>'>"+num+"</a>]&nbsp;";
                }else...{
                    showStr=showStr+"&nbsp;<a href='a.jsp?currentPage="+num+"&pages=<%=pages%>'>"+num+"</a>&nbsp;";
                }
            }        
        }else...{
            var num;
            for(var i=1;i<=10;i++)...{
                num=(currentGroup-1)*10+i;
                if(num==currentPage)...{
                    showStr=showStr+"&nbsp;[<a href='a.jsp?currentPage="+num+"&pages=<%=pages%>'>"+num+"</a>]&nbsp;";
                }else...{
                    showStr=showStr+"&nbsp;<a href='a.jsp?currentPage="+num+"&pages=<%=pages%>'>"+num+"</a>&nbsp;";
                }
            }                
        }

        //向后滚动
        if(currentGroup>=groups)...{
            showStr=showStr+">>";
        }else...{
            showStr=showStr+"<a href='javascript:showPage("+(currentGroup+1)+")'>>></a>";
        }
        
        document.getElementById("show").innerHTML=showStr;
    }

    showPage(group);
</script>