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: >3&9Wbv>
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CountBean.java ;&XC*R+
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/*
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* CountData.java "Iacs s0;
* mpD[k9`x#
* Created on 2007年1月1日, 下午4:44 z\>ZgRi~n
* P?Kg7m W
* To change this template, choose Tools | Options and locate the template under @ssT$#)$!
* the Source Creation and Management node. Right-click the template and choose \{={{O
* Open. You can then make changes to the template in the Source Editor. ) .W0}
*/ _7
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package com.tot.count; V6_~"pRR=
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/** )gV @6w
* W&7(
* @author = VMELk!z
*/ yh{U!hG
public class CountBean { R,8Tt!n
private String countType; y 7z)lBy\
int countId; ( +(bw4V/
/** Creates a new instance of CountData */ 9[h8Dy
public CountBean() {} UTqKL*p523
public void setCountType(String countTypes){ n>xuef
this.countType=countTypes; (#+81 Dr
} 4)Ew
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public void setCountId(int countIds){ l7U<]i GL
this.countId=countIds; {FR+a**
} rVwW%&
public String getCountType(){ ~Xc1y!"9*
return countType; =KHX_ib
} #wJ^:r-c`
public int getCountId(){ izLB4pk$
return countId; |][PbN
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} Nzb=h/;
} (O/W`qo
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CountCache.java N!<X%Ym
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/* HBA|NV3.
* CountCache.java t-Ble
* !8tqYY?>@\
* Created on 2007年1月1日, 下午5:01 .e\PCf9v
* f7Gs1{
* To change this template, choose Tools | Options and locate the template under G6qFAepwi
* the Source Creation and Management node. Right-click the template and choose +No Ve#
* Open. You can then make changes to the template in the Source Editor. #
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*/ :0p$r
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package com.tot.count; qR
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import java.util.*; 10_>EY`
/** uJa.]J~L=
* D8`SI21P
* @author 0CI\Yd=
*/ .f|)od[
public class CountCache { 7?8+h
public static LinkedList list=new LinkedList(); dwb ^z+
/** Creates a new instance of CountCache */ fsWPU]\)
public CountCache() {} 'fZ\uMdTx
public static void add(CountBean cb){ eTI?Mu>C
if(cb!=null){ ycf)*0k
list.add(cb); [buLo*C4:
} NKiWt
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} w`atk=K
} g|j15&x
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CountControl.java -}RGz_LO/
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/* #Vy:6O
* CountThread.java z7pw~Tqlz
* PmtXD6p3(
* Created on 2007年1月1日, 下午4:57 'Jd*r(2d
* wWM[Hus
* To change this template, choose Tools | Options and locate the template under {D8yqO A}
* the Source Creation and Management node. Right-click the template and choose Sx1OY0)s
* Open. You can then make changes to the template in the Source Editor. <&tdyAT?&
*/ *]c~[&x5&
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package com.tot.count; aJ[|80U
import tot.db.DBUtils; +]Ev
import java.sql.*; ei~f1$zc#h
/** wJu9.
* gOMy8w4>
* @author 9)uJ\NMy
*/ 24\^{3nOK
public class CountControl{ :Xu9`5
private static long lastExecuteTime=0;//上次更新时间 i/PL!'oq
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 z6|kEc"{
/** Creates a new instance of CountThread */ uvi&! )x
public CountControl() {} o3:BH@@
public synchronized void executeUpdate(){ 3CPSyF
Connection conn=null; X2{Aa T*M
PreparedStatement ps=null; |O;vWn'U2
try{ U[z2{\
conn = DBUtils.getConnection(); ,:0!+1
conn.setAutoCommit(false); 1?G%&X@
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); _>_"cKS
for(int i=0;i<CountCache.list.size();i++){ b"Jr_24t3v
CountBean cb=(CountBean)CountCache.list.getFirst(); U|8?$/*\
CountCache.list.removeFirst(); g!Ui|]BI9
ps.setInt(1, cb.getCountId()); \y+^r|IL
ps.executeUpdate();⑴ .vd*~U"
//ps.addBatch();⑵ ^FZ9q
} $"va8,
//int [] counts = ps.executeBatch();⑶ yh'*eli
conn.commit(); kIRjoKf <F
}catch(Exception e){ g'2}Y5m$`
e.printStackTrace(); B7sBO6Z$J
} finally{ a6?t?:~|
try{ 8Nx fYA
if(ps!=null) { 6XnUs1O
ps.clearParameters(); ""IPaNHQ
ps.close(); X.ZG-TC
ps=null; L]l?_#*x
} E:[!)UG|y
}catch(SQLException e){} Ox@$ }
DBUtils.closeConnection(conn); mRN[lj
} O`Htdnu
} U*XdFH}vV
public long getLast(){ B] Koi1B
return lastExecuteTime; 3ouo4tf$H.
} cQ3p|a `
public void run(){ "![KQ
long now = System.currentTimeMillis(); y,`q6(&
if ((now - lastExecuteTime) > executeSep) { j"+6aD/lv
//System.out.print("lastExecuteTime:"+lastExecuteTime); #%{
//System.out.print(" now:"+now+"\n"); #A:^XAU1Z@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "2 D{X
lastExecuteTime=now; bNHsjx@
executeUpdate(); Wxgs66
} 3wQ\L=
else{ /K;A bE
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X?] Mzcu
} AjsjYThV
} [q^pMH#U"
} BF"eVKA
//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 Z/:W.*u
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类写好了,下面是在JSP中如下调用。 }IQ! [T5
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<% 1uzK(j8w
CountBean cb=new CountBean(); ^}kYJvqA
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); QwuSo{G
CountCache.add(cb); \2Kl]G(w%y
out.print(CountCache.list.size()+"<br>"); S)"vyGv
CountControl c=new CountControl(); $>Gf;k
c.run(); l a_
out.print(CountCache.list.size()+"<br>"); lxBcO/
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