有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: 0CR;t`M@
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CountBean.java uXC?fMWp.
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/* -,tYfQ;:
* CountData.java t5qAH++axN
* CG7LF
* Created on 2007年1月1日, 下午4:44 7l p VK]
* 5 6R,+sN
* To change this template, choose Tools | Options and locate the template under ,ym;2hJ
* the Source Creation and Management node. Right-click the template and choose +OmSR*fA0
* Open. You can then make changes to the template in the Source Editor. .s?OKy
*/ }X?*o`sW
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package com.tot.count; 2uTa}{/%
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/** aFym&n\
* ^m=%Ctu#
* @author Dfo9jYPf
*/ #jJcgR<
public class CountBean { ChGM7uu2
private String countType; ("6W.i>
int countId; v\eBL&WK
/** Creates a new instance of CountData */ X
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public CountBean() {} (AYS>8O&
public void setCountType(String countTypes){ ss<'g@R
this.countType=countTypes;
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} -Tx tX8v
public void setCountId(int countIds){ pYG,5+g
this.countId=countIds; t["Df;"O
} DE ws+y-*
public String getCountType(){ cZ >W8{G
return countType; .B13)$C
} D3{lyi|8
public int getCountId(){ p#d UL9
return countId; ^Q>*f/.KN
} zf~zYZSr
} "~<~b2Y"5
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CountCache.java B6\VxSX4{
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/* ]LTc)[5Zj
* CountCache.java DZRxp,
* RH Vv}N0
* Created on 2007年1月1日, 下午5:01 L@r.R_*H?s
* a7\L-T+
* To change this template, choose Tools | Options and locate the template under h\d($Ki
* the Source Creation and Management node. Right-click the template and choose 2H[aY%1T
* Open. You can then make changes to the template in the Source Editor. ssITe.,ny
*/ QJWES%m`
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package com.tot.count; 3SDWR@x&
import java.util.*; ;|QR-m2/
/** 03WRj+w
* IGT_
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* @author yQ{_\t1Wd
*/ 2gAdZE&Y
public class CountCache { [V,
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public static LinkedList list=new LinkedList(); YBIe'(p
/** Creates a new instance of CountCache */ *u'`XRJU/
public CountCache() {} y%bqeo
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public static void add(CountBean cb){ OIty
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if(cb!=null){ ',`4 U F
list.add(cb); Y0O<]2yVx
} E)wT+\
} h_G|.7!
} s4`*0_n
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CountControl.java ({kGK0
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/* X1[R*a/p
* CountThread.java ;To+,`?E;q
* OXX(OCG>
* Created on 2007年1月1日, 下午4:57 Pq\V($gN
* ^%$W S,
* To change this template, choose Tools | Options and locate the template under }_ :#fE
* the Source Creation and Management node. Right-click the template and choose q\y#
* Open. You can then make changes to the template in the Source Editor. *Gh8nQbh
*/ ae#HA[\0G
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package com.tot.count; pD_eo6xX
import tot.db.DBUtils; p
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import java.sql.*; Xa%&.&V
/** us,,W(q
* .y_bV=
* @author f.84=epv
*/ :mV7)oWH
public class CountControl{ 4U
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private static long lastExecuteTime=0;//上次更新时间 l)PFzIz=V
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 JS7}K)A2B6
/** Creates a new instance of CountThread */ <\9Ijuq}k
public CountControl() {} QRZTT qG
public synchronized void executeUpdate(){ ^AjYe<RU}
Connection conn=null; KYmWfM3^
PreparedStatement ps=null; l)rvh#D
try{ &B7+>Ix,
conn = DBUtils.getConnection(); 7- 3N
conn.setAutoCommit(false); ;0Ct\ [eh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ])ALAAIc-
for(int i=0;i<CountCache.list.size();i++){ `_g?y)
CountBean cb=(CountBean)CountCache.list.getFirst(); CbH T #
CountCache.list.removeFirst(); pT;-1c%:
ps.setInt(1, cb.getCountId()); xBE
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ps.executeUpdate();⑴ 8&A|)ur4
//ps.addBatch();⑵ >7(~'#x8A"
} zTBi{KrZ
//int [] counts = ps.executeBatch();⑶ am'p^Z@
conn.commit(); Zc\h15+P
}catch(Exception e){ ;GgQ@s@
e.printStackTrace(); <.7I8B7
} finally{ L3=YlX`UL
try{ SL\y\GaV
if(ps!=null) { gC_s\WU
ps.clearParameters(); 23\j1?
ps.close(); 3VRZM@i
ps=null; G0;EbJ/&
} K.iH
}catch(SQLException e){} =y-!k)t
DBUtils.closeConnection(conn); ",aT<lw.
} 8T.5Mhx0jS
} x+*L5$;h
public long getLast(){ ;LF)u2x=
return lastExecuteTime; U3|&Jee
} 4z0R\tjT
public void run(){ '^oGDlkr H
long now = System.currentTimeMillis(); & L.PU@
if ((now - lastExecuteTime) > executeSep) { Nvx)H(8F
//System.out.print("lastExecuteTime:"+lastExecuteTime); DtJTnvG~B
//System.out.print(" now:"+now+"\n"); X~)V )'R
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); TA@tRGP>
lastExecuteTime=now; (9YYv+GGd*
executeUpdate(); +zVcOS*-
} rz[uuY7
else{ gGI#QPT`X
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); =N@)CB7a
} @cS1w'=
} B~_,>WG
} ><#2O
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 HV$9b~(
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类写好了,下面是在JSP中如下调用。 X8,7_D$
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<% R!_8jD:$
CountBean cb=new CountBean(); &Xn8oe
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); bU:}ZO^S
CountCache.add(cb); /XW&q)z-Hl
out.print(CountCache.list.size()+"<br>"); )4'x7Qg/
CountControl c=new CountControl(); _@BRpLs:4
c.run(); sx[&4 k[
out.print(CountCache.list.size()+"<br>"); A'~%_}
%>