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: Dx5X6 t9=
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CountBean.java =`KA@~XH4
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/* chE}TK
* CountData.java Pxvf"SXX
* ZamOYkRX
* Created on 2007年1月1日, 下午4:44 N;q)[Dr
* )
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* To change this template, choose Tools | Options and locate the template under Iysp)
* the Source Creation and Management node. Right-click the template and choose c<a)Yqf"]
* Open. You can then make changes to the template in the Source Editor. *yZ `aKfH
*/ }1#prQ0F
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package com.tot.count; XkhGU?={
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/** FX1H2N(
* EvKzpxCh
* @author X=KC+1e
*/ OfK>-8
public class CountBean { idNra#
private String countType; Rz#q68
int countId; ^?8/9o
/** Creates a new instance of CountData */ ;EB^1*AEw
public CountBean() {} /U
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public void setCountType(String countTypes){ /& W&
this.countType=countTypes; 0NF=7 j
} ZYS]Et[Q
public void setCountId(int countIds){ |JLXgwML
this.countId=countIds; oMNSQMlI
} NXCvS0/h
public String getCountType(){ ='t}d>l
return countType; {[)n<.n[g
} vB%os Qm
public int getCountId(){ +,1 Ea )
return countId; 1N}vz(0"
} eBWgAf.k
} p/U{*i]t
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CountCache.java o1?S*
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/* 0T7t.
* CountCache.java Rc vp@
* )*XD"-9
* Created on 2007年1月1日, 下午5:01 v&qL r+_7
* 2e9.U/9
* To change this template, choose Tools | Options and locate the template under }a%1$>sj
* the Source Creation and Management node. Right-click the template and choose GO)5R,
* Open. You can then make changes to the template in the Source Editor. ?2%;VKN4
*/ U,K=(I7OBX
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package com.tot.count; O.DO,]Uh
import java.util.*; 3yrb7Rn3
/** neQ~h4U"
* bd\%K`JQ{
* @author s1]m^,
*/ G}Ko*:fWS
public class CountCache { f_2(`T#
public static LinkedList list=new LinkedList(); K3iQ/j~a q
/** Creates a new instance of CountCache */ bC/Ql
public CountCache() {} Ew JNpecX
public static void add(CountBean cb){ TM5 Y(Q*
if(cb!=null){ \ZA@r|=$
list.add(cb); L54]l^ls>
} 61w
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} b Rc,Y<
} n?778Wo}
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CountControl.java M-Ek(K3SRf
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/* edo+ o{^
* CountThread.java R GL2S]UFs
* 4f&"1:
* Created on 2007年1月1日, 下午4:57 9a]{|M9
* \zcR75
* To change this template, choose Tools | Options and locate the template under as(/
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* the Source Creation and Management node. Right-click the template and choose y 2)W"PuG
* Open. You can then make changes to the template in the Source Editor. 6e8 gFQ"w2
*/ .DI?-=p|_#
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package com.tot.count; 2qot(Zs1i
import tot.db.DBUtils; K3Bw3j 9
import java.sql.*; e#)NYcr6
/** P{x6e/
* d
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* @author !S%0#d2
*/ 1F_$[iIX]
public class CountControl{ \,fa"^8
private static long lastExecuteTime=0;//上次更新时间 ~yt 7L,OQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `^] D;RfE
/** Creates a new instance of CountThread */ @C<ofg3E
public CountControl() {} &)jq3
public synchronized void executeUpdate(){ _RIlGs\.
Connection conn=null; ah%Ws#&
PreparedStatement ps=null; <D P8a<{{
try{ O}w%$ mq
conn = DBUtils.getConnection(); I tb_ H
conn.setAutoCommit(false); zE<Iv\Q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); dr(-k3ex
for(int i=0;i<CountCache.list.size();i++){ 14"+ctq
CountBean cb=(CountBean)CountCache.list.getFirst(); 7{]dh+)
CountCache.list.removeFirst(); i)'tt9f$
ps.setInt(1, cb.getCountId()); p="0Y<2l
ps.executeUpdate();⑴ Xo:Mar
//ps.addBatch();⑵ !Sw=ns7
} OIJT~Z}
//int [] counts = ps.executeBatch();⑶ v$D U
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conn.commit(); x5CMP%}d
}catch(Exception e){ ?%[~J
e.printStackTrace(); r
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{
} finally{ "X^<g{]
try{ fZj,Q#}D
if(ps!=null) { S43JaSw)
ps.clearParameters(); *:Rs\QH
ps.close(); [}M!ez
ps=null; q-+:1E
} d]Y;rqjue
}catch(SQLException e){} MI'"Xzp{s
DBUtils.closeConnection(conn); 4=o vm[
} ,zdGY]$
} j!w{
public long getLast(){ Gx8!AmeX
return lastExecuteTime; S2e3d
} _3:%b6&Pz
public void run(){ ]'"Sa<->
long now = System.currentTimeMillis(); 641P)
if ((now - lastExecuteTime) > executeSep) { bU}v@Uk
//System.out.print("lastExecuteTime:"+lastExecuteTime); x\U[5d
//System.out.print(" now:"+now+"\n"); "V(P)_
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); K"x_=^,Yu*
lastExecuteTime=now; NhCucSU<K
executeUpdate(); |1"&[ .
} EG`6T
else{ k#zDY*kj
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ;Y[D#Ja-
} ^~.AV]t|
} lOp.cU
} [{Jo(X
//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 :-5[0Mx=
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类写好了,下面是在JSP中如下调用。 Eamt_/LKf
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<% B,cFvS
CountBean cb=new CountBean(); 4~&3.1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); vUVFW'-
CountCache.add(cb); y^,Q M[ &
out.print(CountCache.list.size()+"<br>"); '.1P\>x!]
CountControl c=new CountControl(); QM#Vl19>j(
c.run(); 6e rYjq
out.print(CountCache.list.size()+"<br>"); 2
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%>