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: QR5,_wJ&
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CountBean.java { 1@4}R4
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/* 2Ph7qEBQ22
* CountData.java a4jnu:e
* KBr5bcm4u
* Created on 2007年1月1日, 下午4:44 Wt+y-ES
* cUZ!;*
* To change this template, choose Tools | Options and locate the template under loC5o|Wh
* the Source Creation and Management node. Right-click the template and choose 7c29Ua~[
* Open. You can then make changes to the template in the Source Editor. E7yf[/it
*/ N^Hn9n
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package com.tot.count; /SCZ&
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/** QBfhyo_
* 64!ame}n+
* @author W\>^[c/
*/ I^M#[xA
public class CountBean { bL'#
private String countType; 4VmCW"b7h
int countId; )"_Ff,9Z!
/** Creates a new instance of CountData */ #U$YZ#B
public CountBean() {} X&9^&U=e
public void setCountType(String countTypes){ b>bgUDq
this.countType=countTypes; uq|vNLW26
} Lov.E3S6;
public void setCountId(int countIds){ %89"A'g
this.countId=countIds; P )t]bS
} $&= 4.7Yt
public String getCountType(){ z^P* :
return countType; tIxhSI^
} ~"JE![XR
public int getCountId(){ npO@Haw
return countId; i9&K
} 7#Uz*G\iZ
} hB
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CountCache.java IYfV~+P
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/* B_."?*|w
* CountCache.java 8Fd1;G6
* N;C"X4rV
* Created on 2007年1月1日, 下午5:01 @Z9>3'2]A
* PG^j}
* To change this template, choose Tools | Options and locate the template under &?/N}g@K
* the Source Creation and Management node. Right-click the template and choose +QIGR'3u
* Open. You can then make changes to the template in the Source Editor. ;z.6'EYMG
*/ yfM>8"h@
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package com.tot.count; B?$ 01?9V
import java.util.*; 6z9R1&~%
/** 79{.O`v
* K2x6R
* @author d,Cz-.'sOf
*/ 0a2$P+p
public class CountCache { 7m|`tjQ1
public static LinkedList list=new LinkedList(); ch0oFc$
/** Creates a new instance of CountCache */ 4i_spF-3
public CountCache() {} 9{)Z5%Kz
public static void add(CountBean cb){ n0+g]|a
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if(cb!=null){ ,zAK3d&hj
list.add(cb); U{T[*s
} >W`S(a Mn
} 6CcB-@n4
} '[>\N4WD
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CountControl.java o,S!RG&
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/* /*u#Ba<<
* CountThread.java yxaT7Oqh%
* <X:Ud&\
* Created on 2007年1月1日, 下午4:57
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* 9GMH*=3[=
* To change this template, choose Tools | Options and locate the template under hH<6E
* the Source Creation and Management node. Right-click the template and choose 94~"U5oQ:
* Open. You can then make changes to the template in the Source Editor. 4*0:bhhhf_
*/ "XGD:>Q.
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package com.tot.count; TpJg-F
import tot.db.DBUtils; Zg)_cRR
import java.sql.*; )ZT6:)
/** =dgo!k
* ~A8qeaP
* @author D ?Nd; [
*/ - *:p.(c
public class CountControl{ 5~@?>)TBv
private static long lastExecuteTime=0;//上次更新时间 %/UV_@x&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 EX[B/YH
/** Creates a new instance of CountThread */ Dh
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public CountControl() {} '8s>rH5[V
public synchronized void executeUpdate(){ +mJ
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Connection conn=null; =E&b=
PreparedStatement ps=null; zWy
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try{ If~95fy~c
conn = DBUtils.getConnection(); W3De|V^
conn.setAutoCommit(false); CTl(_g
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); kcLj Kp
for(int i=0;i<CountCache.list.size();i++){ 7]p>XAb
CountBean cb=(CountBean)CountCache.list.getFirst(); _^_5K(Uq
CountCache.list.removeFirst(); <e;jWK
ps.setInt(1, cb.getCountId()); dv"as4~%
ps.executeUpdate();⑴ f'1(y\_fb
//ps.addBatch();⑵ c*N50%=4
} Iq)(UfaSve
//int [] counts = ps.executeBatch();⑶ ctp?y
conn.commit(); {/-y>sm
}catch(Exception e){ mbF(tSy
e.printStackTrace(); rei
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} finally{ dX_!0E[c
try{ Wt>J`
if(ps!=null) { x|.v{tQa
ps.clearParameters(); mfZ)^X
ps.close(); sB?2*S"X)<
ps=null; 8$\Za,)g
} bsB},pc
}catch(SQLException e){} _~tm7o+js
DBUtils.closeConnection(conn); FXS^^p
P
} cb+l"FI7
} ^:m^E0(H
public long getLast(){ p= {Jf}v
return lastExecuteTime; `-4'/~G
} [-4KY4R
public void run(){ :%N*{uy
long now = System.currentTimeMillis(); wz|DT3"Xs
if ((now - lastExecuteTime) > executeSep) { y|^EGnaE
//System.out.print("lastExecuteTime:"+lastExecuteTime); 8s<^]sFP
//System.out.print(" now:"+now+"\n"); VLiIO"u;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9*4 .
lastExecuteTime=now; *dN N<
executeUpdate(); q^5yk=2fq
} :d.1;st
else{ <O.Kqk*
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); doBNghS
} Ski G2n]
} 0|ZVA+
} {{32jU7<
//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 uM<|@`&b
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类写好了,下面是在JSP中如下调用。 Hk@r5<{
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<% >W
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CountBean cb=new CountBean(); eI^gV'UK
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0mTEim
CountCache.add(cb); jO=*:{#x
out.print(CountCache.list.size()+"<br>"); wtSvJI~o)
CountControl c=new CountControl(); Dv@PAnk3C
c.run(); {-HDkG' 8
out.print(CountCache.list.size()+"<br>"); 0E-pA3M6
%>