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: E^0a; |B[
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CountBean.java #. 71O#!
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/* Dy:r)\KX
* CountData.java @>8{J6%\
* <8YvsJ
* Created on 2007年1月1日, 下午4:44 ah,"c9YX
* wk{]eD%
* To change this template, choose Tools | Options and locate the template under LB[?kpy
* the Source Creation and Management node. Right-click the template and choose { `xC~B h
* Open. You can then make changes to the template in the Source Editor. [KCR@__
*/ ^+0>,-)F
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package com.tot.count; X4+H8],)
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/** V(g5Gn?
* `5"3Cj"M
* @author drvrj~o:
*/ uKj(=Rqq
public class CountBean { KzJJ@D*4M]
private String countType; Q- w_@~
int countId; #N%j9
/** Creates a new instance of CountData */ EB@rIvUi,
public CountBean() {} KT7R0 v
public void setCountType(String countTypes){ ddbQFAQQQ
this.countType=countTypes; T%;NW|mH&
} z.+%{_pe
public void setCountId(int countIds){ 1f'msy/
this.countId=countIds; 6 !N2B[9
} &C)97E
public String getCountType(){ gGN6Yqj0
return countType; bAy\Sr
#/
} H/Rzs$pnv
public int getCountId(){ z:
return countId; dK0H.|
} _'<FBlIN
} e {3%-
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CountCache.java $=`d[04
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/* (;H% r &
* CountCache.java Qc=-M'9
* $~VIx% h
* Created on 2007年1月1日, 下午5:01 TuaP
* &0H_W xKeB
* To change this template, choose Tools | Options and locate the template under ;*ni%|K
* the Source Creation and Management node. Right-click the template and choose Wyow MFp
* Open. You can then make changes to the template in the Source Editor. hztqZ:
*/ w9mAeGyE
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package com.tot.count; Rf2mBjJ(z
import java.util.*; /a9CqK
/** WJ LqH<
* {+[Ex2b$
* @author j(}pUV B
*/ ~Nf|,{[(5
public class CountCache {
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public static LinkedList list=new LinkedList(); )vpYVr-
/** Creates a new instance of CountCache */ cd=K=P}p
public CountCache() {} rq Uk_|Xa
public static void add(CountBean cb){ /0$405
if(cb!=null){ a*:GCGe
list.add(cb); %NTJih`
} O%6D2d
} u } +?'B)
} xE$lx:C"FU
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CountControl.java fVVD}GM=
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/* d0&
* CountThread.java FMhuCl2
* )heHERbJ
* Created on 2007年1月1日, 下午4:57 ,}"jiGgS4
* N2Ysi$
* To change this template, choose Tools | Options and locate the template under MJCz %zK
* the Source Creation and Management node. Right-click the template and choose ZLdIEBi=
* Open. You can then make changes to the template in the Source Editor. XHOS"o$y
*/ l N0u1)'2
*-uzsq.W
package com.tot.count; wh2E$b(-
import tot.db.DBUtils; & JJ*?Dl
import java.sql.*; _ n1:v~
/** r .
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* 7$t['2j3
* @author wA)nryXV
*/ #0\* 86
public class CountControl{ k#7A@Vb
private static long lastExecuteTime=0;//上次更新时间 [7g-M/jvY
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 FC||6vJth
/** Creates a new instance of CountThread */ N9y+Psh
public CountControl() {} +_u~Np
public synchronized void executeUpdate(){ ^4'!B
+}F
Connection conn=null; Fs(S!;
PreparedStatement ps=null; ~*UY[!+4^=
try{ 7,8TMd1`M
conn = DBUtils.getConnection(); g}uSIv^
conn.setAutoCommit(false); >"|t*kS
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); tmM; Z(9t
for(int i=0;i<CountCache.list.size();i++){ $$< I}eMd>
CountBean cb=(CountBean)CountCache.list.getFirst(); ):}A Quy]
CountCache.list.removeFirst(); !_;J@B
ps.setInt(1, cb.getCountId()); DL,]iJm
ps.executeUpdate();⑴ m{~L Fhhd1
//ps.addBatch();⑵ m~fDDQs
} 45$aq~%as
//int [] counts = ps.executeBatch();⑶ q)KOI`A
conn.commit(); {MTtj4$
}catch(Exception e){ &-X51O C
e.printStackTrace(); 8V9OMOt!
} finally{ =dQ/^C_hj
try{ 8.7q
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if(ps!=null) { !^v~hD$_q
ps.clearParameters(); z|Yt|W
ps.close(); @A(jo 32
ps=null; C5$?Y8B3
} vy2"B ch
}catch(SQLException e){} fakad#O
DBUtils.closeConnection(conn); uJeJ=7,EO
} OdL/%Zp}
} /L@6Ae
public long getLast(){ +c,
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return lastExecuteTime; T:9M|mD
} E*fa&G~s )
public void run(){ Kp1 F"!
long now = System.currentTimeMillis(); C*B5"s"
if ((now - lastExecuteTime) > executeSep) { *K@O3n
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y6v#0pT
//System.out.print(" now:"+now+"\n"); \Sv|yQUT
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); (TO<SY3AB
lastExecuteTime=now; W:6#0b"_#
executeUpdate(); 25 :v c0
} -m mQ]'.0
else{ kC6Y?g
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4FZ/~Y1}
} |"9vq<`
} i~R+g3oi
} p~""1m01,D
//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 Sm?|,C3V
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类写好了,下面是在JSP中如下调用。 LU`)
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<% ]gm3|-EiY
CountBean cb=new CountBean(); G"kX#k0S
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 51H6
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CountCache.add(cb); |W@Ko%om
out.print(CountCache.list.size()+"<br>"); {?EmO+![}
CountControl c=new CountControl(); i[{*(Y$L
c.run(); >;%QW
out.print(CountCache.list.size()+"<br>"); rO O10g
%>