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: k0IU~y%
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CountBean.java m8PB2h
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/* g\)z!DQ]
* CountData.java R,bcE4WR"
* 7:<Ed"rdE
* Created on 2007年1月1日, 下午4:44 _MEv*Q@o
* %S#"pKE6R
* To change this template, choose Tools | Options and locate the template under L>b,}w
* the Source Creation and Management node. Right-click the template and choose dZgfls
* Open. You can then make changes to the template in the Source Editor. G]1pGA;
*/ //@=Q!MW
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package com.tot.count; 5Z,lWp2A
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/** &zcjU+n
* }AqD0Qd2Hj
* @author )+,jal^7
*/ I}IW!K
public class CountBean { >pvg0Fh
private String countType; V^+:U>$w
int countId; "J{zfWr
/** Creates a new instance of CountData */ Q$L(fHkw
public CountBean() {} yWtr,
public void setCountType(String countTypes){ !y~b;>887
this.countType=countTypes; 5qSZ>DZ
} k#*yhG,]'
public void setCountId(int countIds){ a[g|APZz
this.countId=countIds; W?
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} "@w%TcA
public String getCountType(){ A]%t0>EL<
return countType; :&)/vq
} So.P @CCd
public int getCountId(){ lkg*AAR?'
return countId; ~!9Px j*
} :qTcxzV
} ;OU>AnWr(&
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CountCache.java eSNSnh]'
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/* l)*,18n
* CountCache.java m<"fRT!Y
* \Fg6b6
* Created on 2007年1月1日, 下午5:01 yPh2P5}H>
* Guw|00w,Q$
* To change this template, choose Tools | Options and locate the template under k5;Vl0Ho
* the Source Creation and Management node. Right-click the template and choose (e3Gs+;
* Open. You can then make changes to the template in the Source Editor. )]c3bMVE-
*/ 'Rd*X6dv
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package com.tot.count; s~X*U&}5
import java.util.*; O& %"F8B
/** pNE\@U|4E
* @PoFxv
* @author fCf#zV[
*/ K}E7|gdG
public class CountCache { h<'5q&y
public static LinkedList list=new LinkedList(); Oqpl2Y"/
/** Creates a new instance of CountCache */ -jtC>_/
public CountCache() {} 14n="-9
public static void add(CountBean cb){ t_>bTcsU
if(cb!=null){ dEd ]U49u
list.add(cb); B5,QJ W*
} k)usUP'
} koEX4q
} UcLNMn|
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CountControl.java G</I%qM
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/* q bZ,K@0
* CountThread.java EhIV(q9x
* e4=FU&RpNH
* Created on 2007年1月1日, 下午4:57 1 73<x){
* Z#F,y)YiO
* To change this template, choose Tools | Options and locate the template under 1KYbL8c
* the Source Creation and Management node. Right-click the template and choose _h1 HuL
* Open. You can then make changes to the template in the Source Editor. C?60`^
*/ \%Ah^U)gS
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package com.tot.count; XnE
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import tot.db.DBUtils; yD[zzEuQ
import java.sql.*; 7O+Ij9+{n
/** Ac[|MBaF
* ^5;vx
* @author Cv>yAt.3
*/ $K?T=a;z
public class CountControl{ Z\|u9DO
private static long lastExecuteTime=0;//上次更新时间 'n^2|"$sH
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ntj`+7mw
/** Creates a new instance of CountThread */ Ns.3s7&
public CountControl() {} ;V(H7
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public synchronized void executeUpdate(){ `! nJS|
Connection conn=null; c{mKra
PreparedStatement ps=null; f`hyYp`d5
try{ 6.U"_%
conn = DBUtils.getConnection(); Mhe|eD#)
conn.setAutoCommit(false); rb:<N%*t
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); O->_/_
for(int i=0;i<CountCache.list.size();i++){ K,eqD<
CountBean cb=(CountBean)CountCache.list.getFirst(); cW)Oi^q%o2
CountCache.list.removeFirst(); 3z,v#2
ps.setInt(1, cb.getCountId()); U@.u-)oX
ps.executeUpdate();⑴ r]k*7PK
//ps.addBatch();⑵ jDlA<1
} T!l
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//int [] counts = ps.executeBatch();⑶ /[a|DUoHO
conn.commit(); n}< ir!ZTO
}catch(Exception e){ y#S1c)vU
e.printStackTrace(); M!N`
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} finally{ 4 ,p#:!
try{ eM?rc55|
if(ps!=null) { ta&Q4v&-
ps.clearParameters(); 8To7c
ps.close(); &sm
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ps=null; owE<7TGPI?
} jrm0@K+<IA
}catch(SQLException e){} H<`^w)?
DBUtils.closeConnection(conn); 2X|CuL{]
} m_Mwg
} Z0e-W:&;kF
public long getLast(){ O6yP
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return lastExecuteTime; $d'CBsu|<
} {]&R8?%
public void run(){ JAc@S20v\
long now = System.currentTimeMillis(); .Qd}.EG
if ((now - lastExecuteTime) > executeSep) { 1^aykrnQ>
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;"1/#CY773
//System.out.print(" now:"+now+"\n"); &&X$d!V
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); bt;lq!g
lastExecuteTime=now; fd4;mc1T
executeUpdate(); @&?a]>L
} W|;nJs:e
else{ C@%iQ]=
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [ZuVUOm
} l<:`~\#
} z>6.[Z(T
} c
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//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 u\`/Nhn
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类写好了,下面是在JSP中如下调用。 6|QTS|!
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<% ~\2;i]|
CountBean cb=new CountBean(); ucw`;<d8
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); X*0k>j
CountCache.add(cb); wi>DZkR
out.print(CountCache.list.size()+"<br>"); SijtTY#r
CountControl c=new CountControl(); dIma{uv
c.run(); ,1,&b_
out.print(CountCache.list.size()+"<br>"); ZQ|5W6c
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