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: q<mDs$^K
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CountBean.java _-aQ.p ?T
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/* lub(chCE[
* CountData.java _5'OQ'P2
* g4,>cqRkq
* Created on 2007年1月1日, 下午4:44 ?N2/;u>
* %~ uMa
* To change this template, choose Tools | Options and locate the template under n82N@z<8]
* the Source Creation and Management node. Right-click the template and choose 8Fy$'Zx'
* Open. You can then make changes to the template in the Source Editor. 8&g|iG
*/ 9%e&Z'l
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package com.tot.count; %Q:i6 ~
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/** N S*e<9
* &z[39Q{~
* @author ?bwF$Ku
*/ O,(p><k$/
public class CountBean { Ox ;q +5
private String countType; %[(DFutJY+
int countId; BX :77?9,+
/** Creates a new instance of CountData */ _"
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public CountBean() {} H\7#$ HB
public void setCountType(String countTypes){ P@P(&{@
this.countType=countTypes; et|QW;*L
} Fy!uxT-\
public void setCountId(int countIds){ #g,JNJ}
this.countId=countIds; `6:;*#jO,
} FSZQ2*n5
public String getCountType(){ 7Io]2)V
return countType; x
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} fx@Hd!nO~"
public int getCountId(){ P$z8TDCH
return countId; Ipo?>To
} V?U->0>Z4
} "Sp+Q&2U
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CountCache.java d&K2\n
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/* l]Ozy@
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* CountCache.java =KfV;.&
* u/?s_OR
* Created on 2007年1月1日, 下午5:01 5 _X|U*+5
* '^f,H1oW
* To change this template, choose Tools | Options and locate the template under !~5;Jb>s[/
* the Source Creation and Management node. Right-click the template and choose L~N<<8?\
* Open. You can then make changes to the template in the Source Editor. Dohq@+] O
*/ U
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package com.tot.count; :G$f)NMK
import java.util.*; =!{7ZSu\
/** FG.MV-G
* jt|e?1:vF
* @author 2_lgy?OE`
*/ ,-7w\%*
public class CountCache { +Bk d
public static LinkedList list=new LinkedList(); ()1\b
/** Creates a new instance of CountCache */ 7FL!([S5i
public CountCache() {} 7{HJjH!zx
public static void add(CountBean cb){ y.6D Z
if(cb!=null){ vto^[a6?
list.add(cb); >?iL_YTX
} "N'tmzifh
} f\CJ |tKX
} a4HUP*
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CountControl.java 4QbD DvRQ^
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/* &Rw4ub3
* CountThread.java ql,k 5.l
* (.~#bl
* Created on 2007年1月1日, 下午4:57 0ut/ ')[
* ;Awt: jF
* To change this template, choose Tools | Options and locate the template under 5B3S]@%
* the Source Creation and Management node. Right-click the template and choose 3 @XkO
* Open. You can then make changes to the template in the Source Editor. ! 6yoD
*/ 0#}Ed Q
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package com.tot.count; [@"~'fu0
import tot.db.DBUtils; I}JC ~=`j
import java.sql.*; ?Fgk$WqC
/** hwkm'$}
* oNHbQ&h
* @author WW33ZJ
*/ vR$[#`X
public class CountControl{ 'TWZ@8h~
private static long lastExecuteTime=0;//上次更新时间 xa+=9=<AQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 R;+vE'&CO
/** Creates a new instance of CountThread */ ??&Q"6Oe
public CountControl() {} KF^5 C
public synchronized void executeUpdate(){ P]]re,&R
Connection conn=null; jOL $kiW0
PreparedStatement ps=null; aO:wedfl
try{ G'b*.\=
conn = DBUtils.getConnection(); }F3}-5![
conn.setAutoCommit(false); ciRn"X=l
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); KQ0Zy
for(int i=0;i<CountCache.list.size();i++){ (]*
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CountBean cb=(CountBean)CountCache.list.getFirst(); ?&ie;t<7
CountCache.list.removeFirst(); l{tpFu9v
ps.setInt(1, cb.getCountId()); *x[ZN\$`Y
ps.executeUpdate();⑴ Jq0aDf
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//ps.addBatch();⑵ H4C ]%Q
} +]I7]
//int [] counts = ps.executeBatch();⑶ ;&mefaFlWp
conn.commit(); y;zp*(}f$h
}catch(Exception e){ $yG>=GN
e.printStackTrace(); s;!TB6b@
} finally{ chw6_ctR>
try{ Wk1o H
if(ps!=null) { bgD4;)?5b
ps.clearParameters(); [(Z{5gK
ps.close(); T,z7U2O
ps=null; cXM4+pa=%
} jK`b6:#(,
}catch(SQLException e){} Z$qLY<aV
DBUtils.closeConnection(conn); xUT]6T0dB
} hSQ*_#
} S ]_iobWK
public long getLast(){ 1/b5i8I2v
return lastExecuteTime; )b^yAzL?
} 1F`1(MYt9
public void run(){ {4B{~Qe;
long now = System.currentTimeMillis(); P)7:G?OTx
if ((now - lastExecuteTime) > executeSep) { \@")2o+
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9!CD25u
//System.out.print(" now:"+now+"\n"); \0gU)tVZ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zx:Qz
lastExecuteTime=now; u-v/`F2wN
executeUpdate(); L1P.@hJ
} n*twuB/P 1
else{ )1#J4
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -U&k%X
} 5d ?\>dA
} ?K5S{qG'O
} v6uXik
//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 Jz"Yb
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类写好了,下面是在JSP中如下调用。 < cNJrer
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<% }Xa1K;KM{
CountBean cb=new CountBean(); PfF5@W;E;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !2YvG%t^6
CountCache.add(cb); 3a|I| NP
out.print(CountCache.list.size()+"<br>"); Sfl. &A(
CountControl c=new CountControl(); >;wh0dBe
c.run(); o:oQF[TcFO
out.print(CountCache.list.size()+"<br>"); SSCyq#dl$
%>