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: !8TlD-ZT/
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CountBean.java !44/sr'
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/* .iYJr;9`d
* CountData.java W/=.@JjI
* tP:lP#9
* Created on 2007年1月1日, 下午4:44 9e<.lb^tP
* R"-mKT}
* To change this template, choose Tools | Options and locate the template under F|IAiE
* the Source Creation and Management node. Right-click the template and choose [u
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* Open. You can then make changes to the template in the Source Editor. 0.\/\V:H6
*/ `68@+|#
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package com.tot.count; f&=AA@jLv
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/** GF"hx`zyJ
* ]tim,7s
* @author >1.X*gi?-
*/ ])[[ V!1
public class CountBean { 2Sle#nw3
private String countType; )~GmU9f
int countId; ^6jV_QM#
/** Creates a new instance of CountData */ kGH }[w
public CountBean() {} MS
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public void setCountType(String countTypes){ v3*_9e
this.countType=countTypes; j:Xq1f6a
} pf]xqhL
public void setCountId(int countIds){ 5^}\4.eXo
this.countId=countIds; R a O-H
} ZFA`s
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public String getCountType(){ DMAIM|h
return countType; nyX2|m&
} GiJ *Wp
public int getCountId(){ aH yx_B
return countId; 1ufp qqk
} UZWioxsKr+
} <KJ/<0l
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CountCache.java q?H|o(
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/* &r[`>B{tP
* CountCache.java <S5BDk
* ?Lx24*5%
* Created on 2007年1月1日, 下午5:01
|{&{
* d}OTO10
* To change this template, choose Tools | Options and locate the template under ,xw#NG6
* the Source Creation and Management node. Right-click the template and choose imVo<Je7z(
* Open. You can then make changes to the template in the Source Editor. UI0(=>L
*/ ;RH;OE,A
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package com.tot.count; 8mCxn@yV
import java.util.*; EHSlK5bD,
/** OP;v bZ
* _Mi5g_
* @author j9m_jv
*/ ~Q*%DRd&Z-
public class CountCache { >|J`s~?
public static LinkedList list=new LinkedList(); \0A3]l
/** Creates a new instance of CountCache */ ]q\b,)4
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public CountCache() {} <c*FCblv
public static void add(CountBean cb){ 4aug{}h("
if(cb!=null){ [Hx0`Nc K
list.add(cb); t Cw<Ip
} %3s1z<;R[S
} *}Xf!"I#]N
} :Oy%a'w
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CountControl.java pLl(iNf]
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/* [RS|gem`
* CountThread.java oph}5Krd)
* ;^+\K-O]c
* Created on 2007年1月1日, 下午4:57 .7^c@i[
* .4S.>~^7
* To change this template, choose Tools | Options and locate the template under ]z;P9B3@&
* the Source Creation and Management node. Right-click the template and choose 6S},(=
* Open. You can then make changes to the template in the Source Editor. a a<8,;
*/ V[mT<Lc
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package com.tot.count; Pi=+/}
import tot.db.DBUtils; ;$HftG>B
import java.sql.*; .28<tEf
/** Z~GL5]S
* -7SAK1c$
* @author 1eA7>$w}[
*/ QemyCCP+
public class CountControl{ j*d
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private static long lastExecuteTime=0;//上次更新时间 :{{F *FM;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 97Lte5c6r
/** Creates a new instance of CountThread */ rr/B=O7
public CountControl() {} ^0Zf,40
public synchronized void executeUpdate(){ N1}c9}
Connection conn=null; MlcR"gl*
PreparedStatement ps=null; {vs
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try{ |U~<3.:m:
conn = DBUtils.getConnection(); lVd^
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conn.setAutoCommit(false); 84$nT>c
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?xA:@:l/
for(int i=0;i<CountCache.list.size();i++){ XFg9P}"
CountBean cb=(CountBean)CountCache.list.getFirst(); m)8BgCy
CountCache.list.removeFirst(); v0ujdp,B
ps.setInt(1, cb.getCountId()); vx\r!]
ps.executeUpdate();⑴ ih)zG
//ps.addBatch();⑵ $Y;U[_l#
} v/@^Q1G/:
//int [] counts = ps.executeBatch();⑶ y>:N{|
conn.commit(); 1}S S+>`
}catch(Exception e){ rUwZMli
e.printStackTrace(); bw(a6qKK
} finally{ 'QJ:`)z
try{ V4hiGO[
if(ps!=null) { Fiv3 {.
ps.clearParameters(); ,ZaRy$?
ps.close(); {SOr#{1z*
ps=null; czA5n
} R$v[!A+:'
}catch(SQLException e){} >~#yu&*D
DBUtils.closeConnection(conn); PvzcEV
} 9Q.rMs>qj
} S
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public long getLast(){ dW)B1iUo!
return lastExecuteTime; 2$9odD<r
} Ac96
[
public void run(){ )(A]Ln4
long now = System.currentTimeMillis(); q6@Lp^f
if ((now - lastExecuteTime) > executeSep) { v5/~-uRL%
//System.out.print("lastExecuteTime:"+lastExecuteTime); iM AfJ-oN
//System.out.print(" now:"+now+"\n"); &]g}u5J!=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); -O1>|y2rU
lastExecuteTime=now; au N6prGe
executeUpdate(); ,bXe<L)
} }bs+-K
else{ YA''2Ii
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Az9?Ra;U
} Gp1?iX?ml
} >c1!p]&V
} C\\~E9+
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 \}+_Fo/
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类写好了,下面是在JSP中如下调用。 neB\q[k
6q*9[<8
<% ;i8g41qjF
CountBean cb=new CountBean(); . kQkC:~9
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); M*y)6H k~
CountCache.add(cb); ^({})T0wu
out.print(CountCache.list.size()+"<br>"); H6kR)~zhf
CountControl c=new CountControl(); 3e
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c.run(); +:8fC$vVfC
out.print(CountCache.list.size()+"<br>"); -mAUo;O
%>