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: +9yMtR
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CountBean.java V pY,@qh
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/* jJ'NYG
* CountData.java "&;X/~j
* *M>~$h7
* Created on 2007年1月1日, 下午4:44 w`M`F<_\:
* RjrQDh|((
* To change this template, choose Tools | Options and locate the template under ip*^eS^
* the Source Creation and Management node. Right-click the template and choose 8$IUit h
* Open. You can then make changes to the template in the Source Editor. Y~#F\v
*/ >f1fvv6
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package com.tot.count; %t74*cX
#~qzaETv,
/** fwUF5Y
* $DnR[V}rR!
* @author `/i/AZ{
*/ ^AXH}g
public class CountBean { 1L?W+zMO
private String countType; 8A-*MU`+
int countId; vv5rA 6+
/** Creates a new instance of CountData */ J^PFhu
public CountBean() {} o,0
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public void setCountType(String countTypes){ _oefp*iWS
this.countType=countTypes; 7 ,uD7R_
} *UG?I|l|I
public void setCountId(int countIds){ $kkL)O*"]
this.countId=countIds; lKqFuLHwF
} N1x~-2(
public String getCountType(){ ,&* BhUC
return countType; YOvhMi
} 2jkma :$'
public int getCountId(){ )}_}D+2
return countId; l>(*bb1}b
} bh sCeH
} #~w~k+E4
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CountCache.java k!6m'}v
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/* mGF)Ot R
* CountCache.java h^14/L=|
* W58%Zz4a
* Created on 2007年1月1日, 下午5:01 A
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* 0|=y#`;,Z
* To change this template, choose Tools | Options and locate the template under IfI:|w}:"r
* the Source Creation and Management node. Right-click the template and choose 8&qtF.i-6
* Open. You can then make changes to the template in the Source Editor. *Z2Ko5&Y2
*/ x7jFYC
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package com.tot.count; 6J$I8b#/
import java.util.*; _?I*::
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/** 34_
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* 7lwFxP5QT
* @author ) <w`:wD
*/ U5?QneK
public class CountCache { &W `7 b<
public static LinkedList list=new LinkedList(); ]z#Ita;
/** Creates a new instance of CountCache */ hC]:+.Q+
public CountCache() {} ;!3: 3;
public static void add(CountBean cb){ P1$D[aF9$
if(cb!=null){ dAM]ZR<
list.add(cb); (FGHt/!
} V<ilv<
} S5UQ
} Y^8'P /A
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CountControl.java axN\ZXU
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/* hVd_1|/X
* CountThread.java lWP]}Uy=5~
* [O]rf+NZ(5
* Created on 2007年1月1日, 下午4:57 #v6<9>%
* n(SeJk%>9
* To change this template, choose Tools | Options and locate the template under m6gMVon
* the Source Creation and Management node. Right-click the template and choose zzd PR}VG
* Open. You can then make changes to the template in the Source Editor. gp'k(rGH
*/ )6o%6$c
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package com.tot.count; {qCFd
import tot.db.DBUtils; 3Jj&wHp]
import java.sql.*; .>1Y-NM
/** q [+KQ,
* rA8{Q.L
* @author sx' eu;S
*/ 1/?K/gL
public class CountControl{ rcH{"\F_/
private static long lastExecuteTime=0;//上次更新时间 >>8{N)c5E
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?<Mx* l
/** Creates a new instance of CountThread */ nm%7 e!{m
public CountControl() {} ?_T[]I'
public synchronized void executeUpdate(){ g+?2@L$L
Connection conn=null; g{kjd2
PreparedStatement ps=null; 7fl{<uf
try{ t7,$u-
conn = DBUtils.getConnection(); p+7#`iICE
conn.setAutoCommit(false); 4|4[3Ye7u:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); WB `h)
for(int i=0;i<CountCache.list.size();i++){ zp``e;gY
CountBean cb=(CountBean)CountCache.list.getFirst(); vM:c70=
CountCache.list.removeFirst(); N]\)Ok
ps.setInt(1, cb.getCountId()); r!|h3*YA
ps.executeUpdate();⑴ 6k{gI.SG
//ps.addBatch();⑵ Pw6%,?lQ
} 38:5g_
//int [] counts = ps.executeBatch();⑶ >
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conn.commit(); e ]{=#
}catch(Exception e){ W?[
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e.printStackTrace(); l?L s=J*
} finally{ ln6=XDu
try{ OE _V6Er
if(ps!=null) { p
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ps.clearParameters(); J90
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ps.close(); 4sC)hAx&f
ps=null; X[SIk%{D
} d-8{}Q
}catch(SQLException e){} E#!.;AQ
DBUtils.closeConnection(conn); &(|Ot`el]v
} (io[O?te
} 4C*0MV
public long getLast(){ /R>YDout}
return lastExecuteTime; b8Hzl!zO
} g*w}m>O
public void run(){ JLg/fB3%
long now = System.currentTimeMillis(); OAgZeK$
if ((now - lastExecuteTime) > executeSep) { Id8e%)
//System.out.print("lastExecuteTime:"+lastExecuteTime); DwWm(8&6;}
//System.out.print(" now:"+now+"\n"); *V[I&dKq
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); z>'vS+axV
lastExecuteTime=now; Fw#1?/K~
executeUpdate(); DV)NY!
} 8~BLTZ
else{ oE0~F|(\1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); i8f +woZL
} bh3yH>Zns
} 4RH>i+)pS\
} 5s>>]
.%
//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 B^{~,'
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类写好了,下面是在JSP中如下调用。 TpdYU*z_Br
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<% b S' dXP
CountBean cb=new CountBean(); $0+&xJVn
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }U%T6~_wR
CountCache.add(cb); j'lC]}kH
out.print(CountCache.list.size()+"<br>"); BbPRPkV
CountControl c=new CountControl(); [e{D
c.run(); JEP9!y9y
out.print(CountCache.list.size()+"<br>"); RPjw12Ly
%>