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: U`'w{~"D%
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CountBean.java Ipmr@%~
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/* C[$<7Mi|;
* CountData.java BQ&h&57K
* 5O%}.}n
* Created on 2007年1月1日, 下午4:44 J.`.lQ$z
* 17qrBG-/MD
* To change this template, choose Tools | Options and locate the template under !*#=7^#
* the Source Creation and Management node. Right-click the template and choose I3aEg
* Open. You can then make changes to the template in the Source Editor. &c@I4RV|q
*/ o_$r*Z|HG
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package com.tot.count; CILk
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/** KoXXNJax
* ,>jm|BTD {
* @author Em.?
*/ \1B*iW
public class CountBean { Ia"bP` L
private String countType; YvHn~gNPhs
int countId; ;~q)^.K3
/** Creates a new instance of CountData */ n<$I, IRE
public CountBean() {} 6qA{l_V
public void setCountType(String countTypes){ G0&w#j
this.countType=countTypes; +1623E
} BZ T%+s;u9
public void setCountId(int countIds){ 4'8.f5
this.countId=countIds; J/*[wj
} 5astv:p,P
public String getCountType(){ 6u7HO-aa
return countType; ?{dno=
} [(K^x?\Y0'
public int getCountId(){ C|JWom\J
return countId; 7I
} ljCgIfZ_4
} {gn[
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CountCache.java O#|E7;
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/* #>V;ZV5"
* CountCache.java fe$WR~
* *dl@)~i
* Created on 2007年1月1日, 下午5:01 sig_2;
* 6bn-NY:i
* To change this template, choose Tools | Options and locate the template under "869n37
* the Source Creation and Management node. Right-click the template and choose :U>
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* Open. You can then make changes to the template in the Source Editor. s5dh]vNN
*/ 5*r6#[S\
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package com.tot.count; cG'Wh@
import java.util.*; z=U!D `]v
/** )qIK7;
* (!(bysi9
* @author F*=RP$sj
*/ B+LNDnjO]
public class CountCache { V_kE"W)
public static LinkedList list=new LinkedList(); sFTIRVXN,
/** Creates a new instance of CountCache */ Y(f-e,
public CountCache() {} xd 3
public static void add(CountBean cb){ 2o/`8+eJu
if(cb!=null){ Fqv5WoYVf
list.add(cb); F8I<4S
} @n(In$
} ^q`*!B9@
} Vmc)or*#
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CountControl.java aBnbu
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ccSS au5N
/* v#FUD-Z
* CountThread.java C(t/:?(y
* #`$7$Y~]
* Created on 2007年1月1日, 下午4:57 Xn=fLb(
* K;l'IN"N
* To change this template, choose Tools | Options and locate the template under :S12=sFl$
* the Source Creation and Management node. Right-click the template and choose ?+\,a+46P_
* Open. You can then make changes to the template in the Source Editor. 7fqYSMHR
*/ Dhoj|lc
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package com.tot.count; bRK9Qt#3
import tot.db.DBUtils; Tjqn::~D
import java.sql.*; bph*X{lFK
/** M}Mzm2d#`
* 4;||g@f'[
* @author cIp h$@
*/ i`$rzXcS
public class CountControl{ /(aX>_7jg
private static long lastExecuteTime=0;//上次更新时间 A2d2V**Z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]Yex#K
/** Creates a new instance of CountThread */ ihrrmlN?
public CountControl() {} B(LV22#
public synchronized void executeUpdate(){ val<N293L>
Connection conn=null; (T01hR&
PreparedStatement ps=null; j+hoj2(
try{ 6]S.1BP
conn = DBUtils.getConnection(); "_j7kYAl
conn.setAutoCommit(false); U^&Cvxc[[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); #8jd,I%L
for(int i=0;i<CountCache.list.size();i++){ 3)a29uc:U
CountBean cb=(CountBean)CountCache.list.getFirst(); ltR^IiA}
CountCache.list.removeFirst(); <4,?lZ
ps.setInt(1, cb.getCountId()); }o-P
ps.executeUpdate();⑴ 8B/9{8
//ps.addBatch();⑵
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} w)n]}k
//int [] counts = ps.executeBatch();⑶ z%tu6_4j
conn.commit(); 'wrpW#
}catch(Exception e){ tqCg<NH.!m
e.printStackTrace(); [@Y q^.6t
} finally{ C6~dN&q
try{ /p0LtUMu
if(ps!=null) { us%RQ8=k
ps.clearParameters(); zQ}N
mlk
ps.close(); CaBS0'
n
ps=null; %LHV 0u
} w>_EM&r6~u
}catch(SQLException e){} zP}v2
DBUtils.closeConnection(conn); )6^xIh
} TP::y
} ^^l"brPa
public long getLast(){ 9G+rxyWMW
return lastExecuteTime; D:tZiS=0
} ycD.:w p\'
public void run(){ YCO:bBmp:
long now = System.currentTimeMillis(); W2qQKv
if ((now - lastExecuteTime) > executeSep) { w lg#c6#q
//System.out.print("lastExecuteTime:"+lastExecuteTime); 22~X~=
//System.out.print(" now:"+now+"\n"); :w%bw\}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); l0if#?4\r
lastExecuteTime=now; r$Y!Y#hwQ
executeUpdate(); Ky$G$H
} d/rz0L
else{ LW5ggU/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); $]J IA|
} JSK5x(GlH
} -U[`pUY?f
} y|{?>3
//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 $ n[7
:-" jKw
类写好了,下面是在JSP中如下调用。 "IJMvTmj
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<% qXhf?x
CountBean cb=new CountBean(); _C=[bI@
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >0#q!H,X
CountCache.add(cb); arVf"3a
out.print(CountCache.list.size()+"<br>"); JBAK*g
CountControl c=new CountControl(); XYF~Q9~
c.run(); VQMd[/
out.print(CountCache.list.size()+"<br>"); |o=ST
%>