一个struts的分页－－sql server存储过程版

一个struts的分页－－sql server存储过程版（等数据库）分页（更新）

说是struts分页,实际上这个分页类不局限在某个框架下用的

实现方法是通过list和 map 来封装数据结果集省了建立formbean和手动对formbean赋值的麻烦，

用list和 map 来封装后使用起来和rs基本上一样，有些地方比RS方便些。

本分页类中对查询参数已经作了处理，所以不需要在自己在去拼URL参数了。

sql server分页使用存储过程要更高效些

下面这个存储过程是从SQL区找到的

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CREATE Proc p_show

@QueryStr varchar(8000), --表名、视图名、查询语句

@PageSize int=10,   --每页的大小(行数)

@PageCurrent int=1,   --要显示的页

@FdShow varchar (8000)='', --要显示的字段列表,如果查询结果有标识字段,需要指定此值,且不包含标识字段

@FdOrder nvarchar (3000)='' --排序字段列表

as

declare @FdName nvarchar(550) --表中的主键或表、临时表中的标识列名

 ,@Id1 varchar(80),@Id2 varchar(80) --开始和结束的记录号

 ,@Obj_ID int    --对象ID

--表中有复合主键的处理

declare @strfd nvarchar(4000) --复合主键列表

 ,@strjoin varchar(8000) --连接字段

 ,@strwhere nvarchar(4000) --查询条件

select @Obj_ID=object_id(@QueryStr)

 ,@FdShow=case isnull(@FdShow,'') when '' then ' *' else ' '+@FdShow end

 ,@FdOrder=case isnull(@FdOrder,'') when '' then '' else ' order by '+@FdOrder end

 ,@QueryStr=case when @Obj_ID is not null then ' '+@QueryStr else ' ('+@QueryStr+') a' end

--如果显示第一页，可以直接用top来完成

if @PageCurrent=1

begin

 select @Id1=cast(@PageSize as varchar(50))

 exec('select top '+@Id1+@FdShow+' from '+@QueryStr+@FdOrder)

 return

end

--如果是表,则检查表中是否有标识更或主键

if @Obj_ID is not null and objectproperty(@Obj_ID,'IsTable')=1

begin

 select @Id1=cast(@PageSize as varchar(50))

  ,@Id2=cast((@PageCurrent-1)*@PageSize as varchar(50))

 select @FdName=name from syscolumns where id=@Obj_ID and status=0x80

 if @@rowcount=0   --如果表中无标识列,则检查表中是否有主键

 begin

  if not exists(select 1 from sysobjects where parent_obj=@Obj_ID and xtype='PK')

   goto lbusetemp  --如果表中无主键,则用临时表处理

  select @FdName=name from syscolumns where id=@Obj_ID and colid in(

   select colid from sysindexkeys where @Obj_ID=id and indid in(

    select indid from sysindexes where @Obj_ID=id and name in(

     select name from sysobjects where xtype='PK' and parent_obj=@Obj_ID

   )))

  if @@rowcount>1  --检查表中的主键是否为复合主键

  begin

   select @strfd='',@strjoin='',@strwhere=''

   select @strfd=@strfd+',['+name+']'

    ,@strjoin=@strjoin+' and a.['+name+']=b.['+name+']'

    ,@strwhere=@strwhere+' and b.['+name+'] is null'

    from syscolumns where id=@Obj_ID and colid in(

    select colid from sysindexkeys where @Obj_ID=id and indid in(

     select indid from sysindexes where @Obj_ID=id and name in(

      select name from sysobjects where xtype='PK' and parent_obj=@Obj_ID

    )))

   select @strfd=substring(@strfd,2,2000)

    ,@strjoin=substring(@strjoin,5,4000)

    ,@strwhere=substring(@strwhere,5,4000)

   goto lbusepk

  end

 end

end

else

 goto lbusetemp

/*--使用标识列或主键为单一字段的处理方法--*/

lbuseidentity:

 exec('select top '+@Id1+@FdShow+' from '+@QueryStr

  +' where '+@FdName+' not in(select top '

 

+@Id2+''+@FdName+' from '+@QueryStr+@FdOrder

  +')'+@FdOrder

  )

 return

/*--表中有复合主键的处理方法--*/

lbusepk: 

 exec('select '+@FdShow+' from(select top '+@Id1+' a.* from

  (select top 100 percent * from '+@QueryStr+@FdOrder+') a

  left join (select top '+@Id2+''+@strfd+'

  from '+@QueryStr+@FdOrder+') b on '+@strjoin+'

  where '+@strwhere+') a'

  )

 return

/*--用临时表处理的方法--*/

lbusetemp: 

select @FdName='[ID_'+cast(newid() as varchar(80))+']'

 ,@Id1=cast(@PageSize*(@PageCurrent-1) as varchar(50))

 ,@Id2=cast(@PageSize*@PageCurrent-1 as varchar(50))

exec('select '+@FdName+'=identity(int,0,1),'+@FdShow+'

  into #tb from'+@QueryStr+@FdOrder+'

 select '+@FdShow+' from #tb where '+@FdName+' between '

 

+@Id1+' and '+@Id2

 )

GO

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这里需要建立一个分页类ResultGatherPro.java

相关说明在相应行的后面

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import conn.DBConnManager;//这个是连接池，可以更换其他的。

import javax.servlet.http.HttpServletRequest;

import java.sql.*;

import java.util.*;

public class ResultGatherPro {

    private String sql;

    private int intPageSize; //每页行数

    private int intRowCount;

    private int intPageCount;

    private int intPage; //页号

    private String Counter;

    DBConnManager conn = null;

    Connection con = null;

    CallableStatement stmt = null;

    ResultSet rs = null;

    Statement st = null;

    ResultSet rsc = null;

    private String defaultname = "default";

    public ResultGatherPro() {

    }

    public ResultGatherPro(String sqlcom, int rownum, int pagenum, String counter) {

        System.out.println(counter);

        sql = sqlcom;

        intPageSize = rownum;

        intPage = pagenum;

        Counter = counter;

        System.out.println(sqlcom);

    }

    public void setUseDB(String dbname)

    {

        this.defaultname = dbname;

    }

    public List selectRS(String sqlcom, int rownum, int pagenum, String counter) {

        System.out.println(counter);

        this.sql = sqlcom;

        this.intPageSize = rownum;

        this.intPage = pagenum;

        this.Counter = counter;

        System.out.println(sqlcom);

        return selectRS();

    }

    public List selectRS() {

        List rsall = new ArrayList();

        Map rsTree;

        try {

            conn = DBConnManager.getInstance();

            con = conn.getConnection(defaultname);

            st = con.createStatement();

            rsc = st.executeQuery(Counter);

            while (rsc.next()) {

                intRowCount = rsc.getInt("allrow");

            }

            stmt = con.prepareCall("{call p_show('" + sql + "'," + intPageSize + "," + intPage + ")}");//如果用别的数据库就把这个地方修改一下

            rs = stmt.executeQuery();

            ResultSetMetaData rsmd = rs.getMetaData();

            int numberOfColumns = rsmd.getColumnCount();

            //Object[] aa = new Object[numberOfColumns-1];

            intPageCount = (intRowCount + intPageSize - 1) / intPageSize;

            while (rs.next()) {

                rsTree = new HashMap(numberOfColumns);

                for (int r = 1; r < numberOfColumns + 1; r++) {

                    rsTree.put(rsmd.getColumnName(r).toLowerCase(), rs.getObject(r));//toLowerCase()这个地方把列名转化为小写是为了和oracle兼容

                }

                rsall.add(rsTree);

            }

        } catch (java.lang.Exception ex) {

            System.out.println("db conn has a Exception !!!!");

            if(ex.toString().indexOf("peer")>0||ex.toString().indexOf("reset")> 0) //一般连接池都没有自动重连功能，这里是当数据库连接异常后，进行重新初始化连接。不然即使网络正常了，数据库连接也不会恢复

                DBConnManager.reConnect();

            ex.printStackTrace();

        } finally {

            try {

                if (rsc != null)

                    rsc.close();

                if (st != null)

                    st.close();

                if (rs != null)

                    rs.close();

                if (stmt != null)

                    stmt.close();

                if (conn != null)

                    conn.releaseConnection(defaultname, con);

            } catch (Exception e) {

                System.out.println(e);

            }

        }

        return rsall;

    }

    public String ChangePage(HttpServletRequest request) {

        String urlchange = null;

        String pagename = request.getRequestURI().substring(request.getRequestURI().lastIndexOf("/") + 1);

        String url = getUrl(request);

        String dol = "";

        if (url != null && !url.equals(""))

            dol = "&";

        if (intPage > 1 && intPage < intPageCount) {

            urlchange = "<a href=" + pagename + "?pagenum=" + (intPage - 1) + dol + url + ">上一页</a> | <a href=" + pagename + "?pagenum=" + (intPage + 1) + dol + url + ">下一页</a> | 第" + intPage + "页 | 共" + intPageCount + "页 | 共" + intRowCount + "条";

        } else if (intPage == 1 && intRowCount <= intPageSize) {

            urlchange = "上一页 | 下一页 | 第" + intPage + "页 | 共" + intPageCount + "页 | 共" + intRowCount + "条";

        } else if (intPage == intPageCount && intPage != 1) {

            urlchange = "<a href=" + pagename + "?pagenum=" + (intPage - 1) + dol + url + ">上一页</a> 下一页 | 第" + intPage + "页 | 共" + intPageCount + "页 | 共" + intRowCount + "条";

        } else if (intPage == 1 && intRowCount >= intPageSize) {

            urlchange = "上一页 | <a href=" + pagename + "?pagenum=" + (intPage + 1) + dol + url + ">下一页</a> | 第" + intPage + "页 | 共" + intPageCount + "页 | 共" + intRowCount + "条";

        } else {

            urlchange = "<a href=" + pagename + ">第一页</a>";

        }

        return urlchange;

    }

    public String ChangeBar(HttpServletRequest request) {

        String urlchange = null;

        String pagename = request.getRequestURI().substring(request.getRequestURI().lastIndexOf("/") + 1);

        String url = getUrl(request);

        String dol = "";

        if (url != null && !url.equals(""))

            dol = "&";

        if (intPage > 1 && intPage < intPageCount) {

            urlchange = "<a href=" + pagename + "?pagenum=" + (intPage - 1) + dol + url + ">上一页</a> | <a href=" + pagename + "?pagenum=" + (intPage + 1) + dol + url + ">下一页</a> | 第" + intPage + "页 | 共" + intPageCount + "页";

        } else if (intPage == 1 && intRowCount <= intPageSize) {

            urlchange = "上一页 | 下一页 | 第" + intPage + "页 | 共" + intPageCount + "页";

        } else if (intPage == intPageCount && intPage != 1) {

            urlchange = "<a href=" + pagename + "?pagenum=" + (intPage - 1) + dol + url + ">上一页</a> 下一页 | 第" + intPage + "页 | 共" + intPageCount + "页";

        } else if (intPage == 1 && intRowCount >= intPageSize) {

            urlchange = "上一页 | <a href=" + pagename + "?pagenum=" + (intPage + 1) + dol + url + ">下一页</a> | 第" + intPage + "页 | 共" + intPageCount + "页";

        } else {

            urlchange = "<a href=" + pagename + ">第一页</a>";

        }

        return urlchange;

    }

    public int getTotal() {

        return intRowCount;

    }

    public int getPageCount() {

        return intPageCount;

    }

    public String gotoPage(HttpServletRequest request) {

        String url = getUrl(request);

        String javascript = "<script>function checksearch(sform)/n{if(sform.pagenum.value==/"/" || sform.pagenum.value==/"0/"){alert('请输正确入页数！');sform.pagenum.focus(); return false;}/nif(isNaN(sform.pagenum.value)){alert('请输入数字！'); sform.pagenum.focus();return false;}}</script>";

        String form = "<table  border='0' cellpadding='0' cellspacing='0'>/n" + javascript;

        form += "<form   action='' onSubmit='return checksearch(this)'>/n<tr><td width='40' align='center'>/n<input name='pagenum' type='text' size='3' class='gotext'>/n ";

        if (url != null) {

            if (url.indexOf("&") > 0) {

                String[] param = new String[(url.split("&")).length];

                param = url.split("&");

                for (int i = 0; i < param.length; i++) {

                    form += "<input type='hidden' name='" + param[i].substring(0, param[i].indexOf("=")) + "' value='" + param[i].substring(param[i].indexOf("=") + 1) + "'>/n";

                }

            } else {

                if (url.indexOf("=") > 0) {

                    form += "<input type='hidden' name='" + url.substring(0, url.indexOf("=")) + "' value='" + url.substring(url.indexOf("=") + 1) + "'>/n";

                }

            }

        }

        form += "</td><td width='25' align='center'><input type='submit' name='Submit' value='GO' class='gobtn'>/n</td>/n</tr>/n</form>/n</table>";

        return form;

    }

    private String getUrl(HttpServletRequest request) {

        String url = "";

        Enumeration param = request.getParameterNames();

        while (param.hasMoreElements()) {

            String pname = param.nextElement().toString();

            if (!pname.equalsIgnoreCase("pagenum") && !pname.equalsIgnoreCase("submit"))

                url += pname + "=" + request.getParameter(pname) + "&";

        }

        if (url.endsWith("&")) {

            url = url.substring(0, url.lastIndexOf("&"));

        }

        return url;

    }

    public String intercept(String str, int num, String last) {

        if (str.length() <= num)

            return str;

        else

            return str.substring(0, num) + last;

    }

}

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在action里可以这样调用

可以看到action里没有做对传递参数的处理，只需要把request整个传到分页类里就可以了

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   String sql = "select top 100 percent * from usertable";

   String sqlcount = "select count(*) from usertable";//为了得到总行数

   int pagesize= 18;

   int pagenum = 1;

   if(request.getParameter("pagenum")!=null)

   {

    pagenum = java.lang.Integer.parseInt(request.getParameter("pagenum"));

   }

   ResultGatherPro rs = new ResultGatherPro(sql,pagesize,pagenum,sqlcount);

   request.setAttribute("liststill",rs.selectRS());

   request.setAttribute("changepage",rs.ChangePage(request));

   request.setAttribute("gotopage",rs.gotoPage(request));

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最后 jsp里可以这样写

-------------------------------------------------------------------------------------------------------------------------

<logic:iterate id="listuser" name="liststill" type="Map">

<bean:write name='listuser' property='username'/>   

<bean:write name='listuser' property='useremail'/>      

</logic:iterate>

<bean:write name='changepage' filter="false"/>

 

                <bean:write name='gotopage' filter="false"/>

上面两个一定要设置filter="false" 不然会过滤html部分

如果用mysql数据库

将分页类中

con.prepareCall("{call p_show('" + sql + "'," + intPageSize + "," + intPage + ")}");

改成

con.prepareCall(sql+" limit "+(intPage-1)*intPageSize+","+intPageSize);

如果用oracle数据库

改成

con.prepareCall("SELECT * FROM(SELECT A.*, rownum r FROM("+sql+") A WHERE rownum <= "+intPage*intPageSize+") B WHERE r > "+(intPage-1)

*intPageSize);

最好不要用把所有记录都读出来然后在其中进行分页的方法

 

源文档 <http://www.blogjava.net/jfy3d/archive/2005/05/11/4175.html>