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: 6g'+1%O
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CountBean.java Dqm;twd>
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/* E7|P\^}m(f
* CountData.java w(nQ:;oC
* .$"69[1H
* Created on 2007年1月1日, 下午4:44 u'aWvN y+
* (J`EC
* To change this template, choose Tools | Options and locate the template under ehQ~+x
* the Source Creation and Management node. Right-click the template and choose /w:~!3Aj0+
* Open. You can then make changes to the template in the Source Editor. r r(UE
*/ yx/.4DW1Ua
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package com.tot.count; s%t =*+L\
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/** t`vIcCXqyl
* \m1jV>q
* @author ??=7pFm
*/ oOHr~<
public class CountBean { IsP!ZcV;
private String countType; ph=U<D4
int countId; bd3q207>
/** Creates a new instance of CountData */ S&;D
public CountBean() {} |=ljN7]!
public void setCountType(String countTypes){ nWv6I&
this.countType=countTypes; M7SVD[7~HM
} VseeU;q
public void setCountId(int countIds){ G>0hi1
this.countId=countIds; [USE&_RN
} u
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public String getCountType(){ [7gwJiK
return countType; +xRSd *
} Bhw|!Y&%
public int getCountId(){ ;>B06v
return countId; 3dC;B@
} k^r-~q+NV#
} #BX^"J{~
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CountCache.java pN7 v7rs
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/* ~QE- $;
* CountCache.java :*s+X$x,<
* kK$*,]iCp
* Created on 2007年1月1日, 下午5:01 _hs\"W
* D``>1IA]
* To change this template, choose Tools | Options and locate the template under O,?aVgY
* the Source Creation and Management node. Right-click the template and choose -WK
* Open. You can then make changes to the template in the Source Editor. g'1ASMuR
*/ \9s x_T
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package com.tot.count; @2)ImgK[
import java.util.*; ^Ts8nOGMh
/** J9yB'yE8
* dX5|A_Ex
* @author Rz!! ;<ye8
*/ ELQc:
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public class CountCache { odC}RdN
public static LinkedList list=new LinkedList(); +a((,wAN2
/** Creates a new instance of CountCache */ #gY|T|
public CountCache() {} 0@dN$e
public static void add(CountBean cb){
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if(cb!=null){ ;B@-RfP
list.add(cb); ,]|*~dd>G
} *'nZ|r v
} Hnc<)_DF
} 3eP7vy
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CountControl.java ;OfZEy>7
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/* 088"7 s
* CountThread.java u3@v
* F otHITw[
* Created on 2007年1月1日, 下午4:57 _f@,
>l
* 6b9&V`
* To change this template, choose Tools | Options and locate the template under ;gNoiAxW
* the Source Creation and Management node. Right-click the template and choose 52d8EGC
* Open. You can then make changes to the template in the Source Editor. ZMI
vzQYI
*/ N"rZK/@}
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package com.tot.count; `<^1Ik[g
import tot.db.DBUtils; {kp^@
import java.sql.*; a#4 'X*
/** , 1`-u$
* 2%(RB4+
* @author *oU-V#
*/ Y]>Qu f.!
public class CountControl{ O)Mf/P'
private static long lastExecuteTime=0;//上次更新时间 "/}cV5=Z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 J{bNx8.&
/** Creates a new instance of CountThread */ #Bgq]6G2
public CountControl() {} _F9O4Q4
public synchronized void executeUpdate(){ *QT|J6ng
Connection conn=null; nH% 1lD?:
PreparedStatement ps=null; y OLqIvN
try{ BbdJR]N/!h
conn = DBUtils.getConnection(); &i%1\o
conn.setAutoCommit(false); ccu13Kr>E
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); -!b@\=
for(int i=0;i<CountCache.list.size();i++){ @CU~3Md*
CountBean cb=(CountBean)CountCache.list.getFirst(); y:3d`E4Xw
CountCache.list.removeFirst(); [Y=X^"PF
ps.setInt(1, cb.getCountId()); '4}c1F1T_
ps.executeUpdate();⑴ <UMT:`h1MZ
//ps.addBatch();⑵ 37QXML
} ]J* y`jn
//int [] counts = ps.executeBatch();⑶ lTn~VsoRZ
conn.commit(); ~ok i s
}catch(Exception e){ O9tgS@*Tv
e.printStackTrace(); bxA1fA;
} finally{ @Xb>GPVe#L
try{ =ykOh_M
if(ps!=null) { C#A\Rfi
ps.clearParameters(); 5zBayJh#
ps.close(); d$(>=gzBQ
ps=null; ;c;n.o.)/#
} wu2C!gyBo
}catch(SQLException e){} `Ufv,_n
DBUtils.closeConnection(conn); Vdz(\-}ao
} GxR, 3
} {BlKVsQ
public long getLast(){ Ud8*yB
return lastExecuteTime; ';hTGLq\X
} xFY<
ns
public void run(){ ~1yMw.04V
long now = System.currentTimeMillis(); tuiQk=[c
if ((now - lastExecuteTime) > executeSep) { bn$}U.m$-
//System.out.print("lastExecuteTime:"+lastExecuteTime); j |tu|Q
//System.out.print(" now:"+now+"\n"); ^,M&PP6
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &G"r>,HU
lastExecuteTime=now; &RP}w%I1
executeUpdate(); \1p5$0z
} f YuM`O
else{ ^sjL@.'m$N
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); L!]~J?)
} pt!Q%rXm
} 3]9twfF 'J
} Jqt&TqX@s
//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 >`@yh-'r
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类写好了,下面是在JSP中如下调用。 k-LT'>CWl
M"t=0[0DM:
<% yU@~UCmja
CountBean cb=new CountBean(); BOQeP/>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); khW9n*
CountCache.add(cb); X0.-q%5
out.print(CountCache.list.size()+"<br>"); u70-HFI@
CountControl c=new CountControl(); [8K+zT5
c.run(); v 8`)h<:W?
out.print(CountCache.list.size()+"<br>"); OJ'x>kE
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