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: QYThW7S
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CountBean.java V{Q kN7-
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/* %c6E-4b
* CountData.java "<l<&
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* G5'_a$
* Created on 2007年1月1日, 下午4:44 ]7qiUdxt:
* fUcLfnr
* To change this template, choose Tools | Options and locate the template under &:#m&,tQ
* the Source Creation and Management node. Right-click the template and choose LAZVW</
* Open. You can then make changes to the template in the Source Editor. -p#,5}
*/ zX5G;,_
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package com.tot.count; hG Apuy
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/** g*-2*
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* |pWaBh|r
* @author 6f]r Q9
*/ yBn_Kd
public class CountBean { FrZ]=:
private String countType; p#H]\P'
int countId; QB1M3b
/** Creates a new instance of CountData */ Q_}/ Pn$1
public CountBean() {} m)f|:MM
public void setCountType(String countTypes){ `mB.pz[
this.countType=countTypes; 4#Eul
} d\Jji 6W
public void setCountId(int countIds){ lfS;?~W0k
this.countId=countIds; !dv-8C$U
} Hq
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public String getCountType(){ *W^=XbG
return countType; vg^Myn
} O{n<WQd{CY
public int getCountId(){ 5N1 K~".
return countId; Vm!i
} eoJ]4-WFq
} \p6 }
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CountCache.java jp m#hH{R
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/* fS./y=j(X
* CountCache.java 6GKT yN
* $pFk"]=
* Created on 2007年1月1日, 下午5:01 f9']
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* Kpg:yrc['
* To change this template, choose Tools | Options and locate the template under oBw}hH,hp
* the Source Creation and Management node. Right-click the template and choose %3,xaVN
* Open. You can then make changes to the template in the Source Editor. ?~)Ak`=
*/ 0>Fqx{!heq
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package com.tot.count; G?[-cNdk
import java.util.*; %N{sD[^
/** QGPR.<D)B
* MFTC6L+T
* @author qeMv
Vf
*/ od,tfLw4
public class CountCache { oEAfowXSqk
public static LinkedList list=new LinkedList(); uL>:tb
/** Creates a new instance of CountCache */ eycV@|6u*
public CountCache() {} jYdV?B
public static void add(CountBean cb){ 8vJdf9pB*
if(cb!=null){ m"-G6BKS
list.add(cb); aQh?}=d a
} l;5`0N?QO
} Uh\]?G[G
} <bX 1,}?
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CountControl.java 6z]`7`G
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/* ~'[jBn)
* CountThread.java 3M$X:$b
* Dqr9Vv
* Created on 2007年1月1日, 下午4:57 6UI>GQ
* ;z0"Ox=7
* To change this template, choose Tools | Options and locate the template under oeGS
* the Source Creation and Management node. Right-click the template and choose Bbs5f@E
* Open. You can then make changes to the template in the Source Editor. N
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*/ >
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package com.tot.count; =kO@ Gk?
import tot.db.DBUtils; 5Jw"{V?Ak
import java.sql.*; fKYKW?g;)Z
/** ni0LQuBp
* Y^5"qd|`
* @author j ]HE>
*/ uTw|Q{ f
public class CountControl{ pe#*I/)b
private static long lastExecuteTime=0;//上次更新时间 Yhk6Uog{4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 pVz pN8!
/** Creates a new instance of CountThread */ tnL."^%A2I
public CountControl() {} 1g81S_T
.
public synchronized void executeUpdate(){ 6puVw-X
Connection conn=null; z'e1"Y.
PreparedStatement ps=null; i;avwP<0
try{ S[.5n]
conn = DBUtils.getConnection(); TnxU/)
conn.setAutoCommit(false); i^/DiWdyf
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .h!9wGi`
for(int i=0;i<CountCache.list.size();i++){ _r7=&oL.Q
CountBean cb=(CountBean)CountCache.list.getFirst(); @e={Wy+Vm(
CountCache.list.removeFirst(); NlMQHma
ps.setInt(1, cb.getCountId()); EaCZx
ps.executeUpdate();⑴ Fu
mn9
//ps.addBatch();⑵ @92gb$xT
} uc\.oG;~q
//int [] counts = ps.executeBatch();⑶ Hp*gv/0
conn.commit(); Es~DHX
}catch(Exception e){ -7,vtd[h
e.printStackTrace(); gb9[Meg'
} finally{ >eu
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try{ 8k%H[Smn:
if(ps!=null) { o6/Rx#A
ps.clearParameters(); .&L^J&V
ps.close(); ^^'[%ok
ps=null; =E;
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} CHg]U l
}catch(SQLException e){} Z3Gm
DBUtils.closeConnection(conn); ,NDxFy;d
} +&?'KZ+Z_v
} l&$*}yCK
public long getLast(){ FQQ@kP$.
return lastExecuteTime; `TAcZl=8
} dJaEoF
public void run(){ =;g= GcVK
long now = System.currentTimeMillis(); L[1d&d!p
if ((now - lastExecuteTime) > executeSep) { OAY8,C=M
//System.out.print("lastExecuteTime:"+lastExecuteTime); y
'mlee
//System.out.print(" now:"+now+"\n"); TXx'7[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); v=j>^FZ
lastExecuteTime=now; GU5W|bS
executeUpdate(); *|sxa#
} ujow?$&
else{ B6(h7~0(<
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); v<%]XHN
} XEa~)i{O
} \N4d_fPj
} `)LIVi"(D
//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 /XjN%|
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类写好了,下面是在JSP中如下调用。 mQFa/7FX
:mzCeX8 *
<% Cv0&prt
CountBean cb=new CountBean(); QZ?O;K1|y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); H'D#s;SlR
CountCache.add(cb); i+U@\:=
out.print(CountCache.list.size()+"<br>"); Ko@zk<~"[
CountControl c=new CountControl(); HUK"OH
c.run(); (K<Z=a
out.print(CountCache.list.size()+"<br>"); Tln9q0"W
%>