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: &3Zy|p4V<
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CountBean.java 3M0+"l(X
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/* QR">.k4QJ
* CountData.java +Ug/rtK4
* 3u>8\|8wz
* Created on 2007年1月1日, 下午4:44 T<-=nX
* 8SmnMt
* To change this template, choose Tools | Options and locate the template under #,(sAj
* the Source Creation and Management node. Right-click the template and choose Gq#~vr
* Open. You can then make changes to the template in the Source Editor. jxgj,h"}9`
*/
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package com.tot.count; zu2HH<E
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/** QHBtWQgS
* Z.i{i^/#(
* @author sP'0Sl~NU
*/ !5}l&7:(MN
public class CountBean { xKOq[d/8
private String countType; k;dXOn
int countId; w>xV
/** Creates a new instance of CountData */ 'rb'7=z5
public CountBean() {} rSP_:}
public void setCountType(String countTypes){ KyP)Qzp
this.countType=countTypes; $!A:5jech
} w'7R4
public void setCountId(int countIds){ HjWq[[Nz
this.countId=countIds; >i,iOx|E-
} T:asm1BC[
public String getCountType(){ T_<BVM
return countType; H/~?@CE(YC
} M~6@20$oW
public int getCountId(){ Lp:6 ;
return countId; Bz2'=~J
} (3,.3)%`
} J?:[$ C5
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CountCache.java o5Rz%k#h
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/* ?Ce#BwQ>
* CountCache.java 10sK]XI
* oholt/gb+0
* Created on 2007年1月1日, 下午5:01 u>T76,8|\
* e5v`;(^M
* To change this template, choose Tools | Options and locate the template under =
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* the Source Creation and Management node. Right-click the template and choose :_dICxaLZT
* Open. You can then make changes to the template in the Source Editor. q(z7~:+qNr
*/ vrl[BPI
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package com.tot.count; FY;+PY@I{
import java.util.*; uf) Oy7FQ
/** nZvU'k:
* Db03Nk>#
* @author /nB'kg[h\
*/ ?p8Qx\%*
public class CountCache { ?KN:r E
public static LinkedList list=new LinkedList(); ^3I'y
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/** Creates a new instance of CountCache */ ML!9:vz
public CountCache() {} 6517Km 4-
public static void add(CountBean cb){ wgd<3 X
if(cb!=null){ r:l96^xs
list.add(cb); Xza4iV
} $-pbw@7
} xl!K;Y2<
} CUhV$A#oo
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CountControl.java #Q6w+"
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/* /mbCP>bcG
* CountThread.java %O) Z
* !]DuZ=
* Created on 2007年1月1日, 下午4:57 1$["79k
* ?n*fy
* To change this template, choose Tools | Options and locate the template under ,Aa|Bd]b
* the Source Creation and Management node. Right-click the template and choose dK# h<q1
* Open. You can then make changes to the template in the Source Editor. VO9f~>`(
*/ G,DOBA
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package com.tot.count; K\sbt7~
import tot.db.DBUtils; EzP#Mnz^
import java.sql.*; (|0b7|'T
/** ]gP8?s|
* 0eA5zFU7
* @author aJ-}
*/ YC)hX'A\
public class CountControl{ uX0
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private static long lastExecuteTime=0;//上次更新时间 qc-C>Ra
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |Y{PO&-?r
/** Creates a new instance of CountThread */ h]}`@M"
public CountControl() {} zlMlMyG4
public synchronized void executeUpdate(){ 4<yK7x
Connection conn=null; .;Z.F7{q
PreparedStatement ps=null; LhKY}R
try{ +E#PJ_H=F8
conn = DBUtils.getConnection(); w{P6i<J
conn.setAutoCommit(false); kknhthJ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8_awMVAy
for(int i=0;i<CountCache.list.size();i++){ "i''Ui\H
CountBean cb=(CountBean)CountCache.list.getFirst(); P' FKk<
CountCache.list.removeFirst(); th Q J(w
ps.setInt(1, cb.getCountId()); d"l}Ny)C
ps.executeUpdate();⑴ iE+6UK
//ps.addBatch();⑵ %(NN*o9"q
} LH.%\TMN$
//int [] counts = ps.executeBatch();⑶ s?+fPOF
conn.commit();
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}catch(Exception e){ R}.3|0
e.printStackTrace(); ul$omKI$}
} finally{ VK$zq5D
try{ ,N;v~D$Y
if(ps!=null) { &$Ci}{{n#
ps.clearParameters(); 2moIgJ
ps.close(); JQH7ZaN
ps=null; PuU*vs3
} fT
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}catch(SQLException e){} 6*V8k%H
DBUtils.closeConnection(conn); >OTl2F}4 !
} .CvFE~
} ^Bn1;
public long getLast(){ x36NL^
return lastExecuteTime; m/KjJ"s,
} ,.q8Xf
public void run(){ J[MVE4&
long now = System.currentTimeMillis(); *H?t;,\
if ((now - lastExecuteTime) > executeSep) { y78z>(jV
//System.out.print("lastExecuteTime:"+lastExecuteTime); wU.'_SBfB
//System.out.print(" now:"+now+"\n"); M!-q}5' ;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !&\meS{
lastExecuteTime=now; ^YqbjL
executeUpdate(); h9U+%=^O
} h2AGEg'g2[
else{ (A2U~j?Ry}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); a&8l[xe1
} {q})kO
} <TL])@da
} SC]6F*
//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 \A ;^ UxG
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类写好了,下面是在JSP中如下调用。 +&(Jn
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<% zv`zsqDJ
CountBean cb=new CountBean(); xP42xv9U
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }Z^FEd"y
CountCache.add(cb); QZ#3Bn%B5
out.print(CountCache.list.size()+"<br>"); j`{fB}
CountControl c=new CountControl(); uF+);ig
c.run(); MPqY?KF
out.print(CountCache.list.size()+"<br>"); ;g&7*1E
%>