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: dU#-;/}o
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CountBean.java 0k#7LubWZl
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/* -V4%f{9T3
* CountData.java QgI[#d{
* y^"@$
* Created on 2007年1月1日, 下午4:44 p- a{6<h
* ~o>Gm>5!HH
* To change this template, choose Tools | Options and locate the template under L
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* the Source Creation and Management node. Right-click the template and choose drMMf[
* Open. You can then make changes to the template in the Source Editor. gW,hI>
*/ {#:31)P
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package com.tot.count; j*5IRzK1%0
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/** EJ>&\Iq
* fZezDm(Q
* @author +J|H~`
*/ pB4Uc<e
public class CountBean { @)BO`;*$fF
private String countType; r\d(*q3B
int countId; 43pe6 ^.
/** Creates a new instance of CountData */ |mP};&b
public CountBean() {} lH;V9D^
public void setCountType(String countTypes){ A#6zINK#B
this.countType=countTypes; LQHL4jRXU
} (-g*U#
public void setCountId(int countIds){ 1$8@CT^m
this.countId=countIds; ~_-]>
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} jM&di
public String getCountType(){ +Q[uq!<VJk
return countType; L;*
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} NNF"si\FE
public int getCountId(){ 3*&
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return countId; 0:`|T jf_
} .07`nIs"
} ~N/r;omVc
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CountCache.java X%+lgm+
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/* JwB'B
* CountCache.java #D4
* &s='$a;4
* Created on 2007年1月1日, 下午5:01 UWF
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* [Q0V 5P~Q'
* To change this template, choose Tools | Options and locate the template under Bz<hP*.O
* the Source Creation and Management node. Right-click the template and choose ZRG
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* Open. You can then make changes to the template in the Source Editor. >Jmla~A
*/ )-26(aNGT
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package com.tot.count; H.m]Dm,z
import java.util.*; !JDr58
/** |ZL?Pqki
* {2h*NFp
* @author vY-CXWC7
*/ \ dFE.4
public class CountCache { 0k5-S~_\
public static LinkedList list=new LinkedList(); oGRk/@
/** Creates a new instance of CountCache */ =nGFLH6)
public CountCache() {} %+H _V1F
public static void add(CountBean cb){ 3l~+VBR_
if(cb!=null){ BYB4-,
list.add(cb); `UTPX'Vz
} D xV=S0P
} ${MzOi
} x-m*p^}
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CountControl.java SHX`/
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/* @"@|O>KJ
* CountThread.java q1T)H2S
* ->rqr#
* Created on 2007年1月1日, 下午4:57 s`jlE|jtN
* n.&7lg^X
* To change this template, choose Tools | Options and locate the template under {+WBi(=W
* the Source Creation and Management node. Right-click the template and choose w6i2>nu_O
* Open. You can then make changes to the template in the Source Editor. ryVYY>*(K
*/ oI;ho6y)
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package com.tot.count; E{<#h9=>
import tot.db.DBUtils; t,?,T~#9
import java.sql.*; 2%sZaM
/** (dq_,LI
* o]q~sJVk6
* @author u]Ku96!
*/ *S ag
public class CountControl{ F:!6B b C
private static long lastExecuteTime=0;//上次更新时间 u%~'+=
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )2Ei<
/** Creates a new instance of CountThread */ y:RW:D&
public CountControl() {} F
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public synchronized void executeUpdate(){ ENuL!H>;*
Connection conn=null; `eMZhYo
PreparedStatement ps=null; gz~oQ
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try{ d}\]!x3t
conn = DBUtils.getConnection(); ryL1<u
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conn.setAutoCommit(false); S=_u3OH0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); J<0{3pZY
for(int i=0;i<CountCache.list.size();i++){ 9wYm(7M6
CountBean cb=(CountBean)CountCache.list.getFirst(); ^OKm (
CountCache.list.removeFirst(); f~NS{gL*
ps.setInt(1, cb.getCountId()); J8emz8J
ps.executeUpdate();⑴ KL'1)G"OH
//ps.addBatch();⑵ o8R_Ojh
} N4vcd=uG#
//int [] counts = ps.executeBatch();⑶ EB}B75)x
conn.commit(); h$&Tg_/'#D
}catch(Exception e){ CPJ21^
e.printStackTrace(); @Chl>s
} finally{ `;j1H<L
try{ ]lwf6'
if(ps!=null) { +MX~1RU+
ps.clearParameters(); KnkmGy
ps.close(); ^Kz?SO
ps=null; :}e<
} 8\rca:cF
}catch(SQLException e){} gw)4P tb!
DBUtils.closeConnection(conn); ,D;8~llM
} <[k3x8H'
} #c:s2EL
public long getLast(){ ^3dc#5]Xf
return lastExecuteTime; K1 "HJsj
} yMN JHiE/
public void run(){ K,g6y#1"
long now = System.currentTimeMillis(); M{J>yN
if ((now - lastExecuteTime) > executeSep) { 9<u&27.
//System.out.print("lastExecuteTime:"+lastExecuteTime); q-(~w!e
//System.out.print(" now:"+now+"\n"); ni/s/^
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6{I7)@>N
lastExecuteTime=now; v 6
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executeUpdate(); L<!h3n
} b-_l&;NWg
else{ ;0dH@b
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1Vy8eI`4
} 4;6"I2;zfG
} =3035{\
} @@D/&}#F
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 9
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类写好了,下面是在JSP中如下调用。 z:-{Y2F
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<% X%YZQc9
CountBean cb=new CountBean(); jA1S|gV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xRWfZ3E#
CountCache.add(cb); oDZZ
out.print(CountCache.list.size()+"<br>"); \^(#b,k#
CountControl c=new CountControl(); }rJqMZ]w
c.run(); 6|EOB~|
out.print(CountCache.list.size()+"<br>"); BbX$R`f
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