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: .# !'c
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CountBean.java TbKP8zw{
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/* H)`C ncB
* CountData.java xf V,==uF
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* Created on 2007年1月1日, 下午4:44 _C< 6349w
* QD.zU/F~>
* To change this template, choose Tools | Options and locate the template under 7]/dg*A )C
* the Source Creation and Management node. Right-click the template and choose K9e~Wl<3
* Open. You can then make changes to the template in the Source Editor. 2Y E;m&
*/ 4T-,'P{?
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package com.tot.count; 6?3/Ul}
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/** IgPV#
* ^eTDD
* @author T:K"
*/ u%6Irdx
public class CountBean { Z/89&Uy`h
private String countType; lj
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int countId; NCowt|#t
/** Creates a new instance of CountData */ YVQ_tCC_!
public CountBean() {} la
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public void setCountType(String countTypes){ RLYU\@kK?
this.countType=countTypes; 18DTv6?QG
} M>*0r<qn
public void setCountId(int countIds){ Vl5SL{+D
this.countId=countIds; _o@(wGeu#
} G$?|S@I,
public String getCountType(){ 2Ueq6IuQ
return countType; !Y ;H(.A/
} N5pinR5 H
public int getCountId(){ P &;y]
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return countId; Od0S2hHO
} Q!4i_)rM
} ${A5-
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CountCache.java ,{.zh&=4
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/* :V&N\>Wo
* CountCache.java , vY)n6
* uL2"StW
* Created on 2007年1月1日, 下午5:01 .ocx(_3G
* Zu\p;!e
* To change this template, choose Tools | Options and locate the template under 2Pbe~[
* the Source Creation and Management node. Right-click the template and choose Q)x?B]b-
* Open. You can then make changes to the template in the Source Editor. w{k1Y+1
*/ RL?u n}Qa
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package com.tot.count; Ni+3b
import java.util.*; Jt##rVN
/** zq,iLoY[R
* iP<k1#k
* @author >;&Gz-lm
*/ |HrM_h<X
public class CountCache { ;EgzC^2e
public static LinkedList list=new LinkedList(); `^v4zWDK
/** Creates a new instance of CountCache */
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public CountCache() {} u9TzZ
public static void add(CountBean cb){ G 6Wx3~
if(cb!=null){ ( MB`hk-d
list.add(cb); M
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} `d75@0:
} Gs+\D0o!
} ANckv|&'v
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CountControl.java `@h:_d
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/* DZ^=*.
* CountThread.java X Y~;)<s_
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* Created on 2007年1月1日, 下午4:57 7SBM^r}
* ?QGmoQ)
* To change this template, choose Tools | Options and locate the template under %0vTA_W
* the Source Creation and Management node. Right-click the template and choose d!`lsh@tF
* Open. You can then make changes to the template in the Source Editor. )8[ym/m
*/ q\a[S*
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package com.tot.count; 7N>oY$&)
import tot.db.DBUtils;
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import java.sql.*; 92!JKZe
/** Xc\*9XV:
* kt:)W])V
* @author UE^D2 u
*/ +AB6lv
public class CountControl{ A^pu
private static long lastExecuteTime=0;//上次更新时间 1<`9HCm
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 w|=gSC-o
/** Creates a new instance of CountThread */ N6h1|_o
public CountControl() {} 6MuWlCKF8
public synchronized void executeUpdate(){ (YIhTSL"]
Connection conn=null; Z)/6??/R
PreparedStatement ps=null; Kaf>
try{ `8,w[o oC2
conn = DBUtils.getConnection(); PfyRZ[3)c
conn.setAutoCommit(false); fCB:733H
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "ml?7Xl,n
for(int i=0;i<CountCache.list.size();i++){ Yj)
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CountBean cb=(CountBean)CountCache.list.getFirst(); Xq|nJ|h
CountCache.list.removeFirst(); WM/#.
ps.setInt(1, cb.getCountId()); O:1DOUYXs
ps.executeUpdate();⑴ -PM)EGSk{
//ps.addBatch();⑵ h}avX*Lx_
} qtHfz"p
//int [] counts = ps.executeBatch();⑶ +O'vj
conn.commit(); {1~9vHAZ
}catch(Exception e){ 9SY(EL
e.printStackTrace(); JX{KYU
} finally{ 3wZ(+<4i
try{ 6_*!|g
if(ps!=null) { Sr&T[ex,.
ps.clearParameters(); N=#4L$@-
ps.close(); Id%_{),HX
ps=null; }&1Iyb
} *wwhZe4V
}catch(SQLException e){} yLW/ -%I#u
DBUtils.closeConnection(conn); $&IpX M]
} z5 Bi=~=#
} @F?=a*s"!
public long getLast(){ gv9=quG
return lastExecuteTime; PRD_!VOW
} |1"!kA
public void run(){ Vu[:A
long now = System.currentTimeMillis(); hY+R'9
if ((now - lastExecuteTime) > executeSep) { _9NVE|c;
//System.out.print("lastExecuteTime:"+lastExecuteTime); ET)>#zp+s
//System.out.print(" now:"+now+"\n"); a+41Ojv (
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .jU Z
lastExecuteTime=now; "<*awWNI
executeUpdate(); -u|l}}bh
} -l
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else{ 0 O~p7D
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); M/{g(|{
} A:eG5K}
} _R7 w?!t8
} t}Ss=0dJO
//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 :mpiAs<%U"
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类写好了,下面是在JSP中如下调用。 o 7G> y#Y
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<% Wr>(#*r7q
CountBean cb=new CountBean(); pCC 7(Ouo
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9=
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CountCache.add(cb); dv7<AJ
out.print(CountCache.list.size()+"<br>"); m"4B!S&Fc(
CountControl c=new CountControl(); s*Ih_Ag=:
c.run(); PKA }zZ
out.print(CountCache.list.size()+"<br>"); nLy#|C
%>