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: IG\Cj7{K^
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CountBean.java oC}
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/* Sp?e!`|8
* CountData.java /:{4,aX2
* RL\?i~'KH
* Created on 2007年1月1日, 下午4:44 <}'=@a
* L<iRqayn
* To change this template, choose Tools | Options and locate the template under {_L l'S
* the Source Creation and Management node. Right-click the template and choose G9am}qr
* Open. You can then make changes to the template in the Source Editor. oD9L5c)
*/ An`*![
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package com.tot.count; F#)bGi
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/** fI<d&5&g
* ]91QZ~4a
* @author UU[z\^w| E
*/ .p o,.}
public class CountBean { &Ruq8n<
private String countType; mvTp,^1
int countId; Jd v;+HN[
/** Creates a new instance of CountData */ '3sySsD&O
public CountBean() {} $%'3w~h`
public void setCountType(String countTypes){ vGPsjxk&
this.countType=countTypes; #639N9a~
} dS <*DP
public void setCountId(int countIds){ d+5~^\lV
this.countId=countIds; {,*vMQ<^
} 3iX\):4
public String getCountType(){ `$6~QLUf
return countType; o[WDPIG
} Z
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public int getCountId(){ u^JsKG+,:
return countId; i'>5vU0?3
} goF87^M
} [eOv fD
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CountCache.java dkDPze9l
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/*
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* CountCache.java bX:h"6{=R
* q3h&V
* Created on 2007年1月1日, 下午5:01 dT?3Q;>B?
* T,>L
* To change this template, choose Tools | Options and locate the template under nfGI4ZE
* the Source Creation and Management node. Right-click the template and choose kQ lwl9
* Open. You can then make changes to the template in the Source Editor. dVHbIx
*/ cL03V? }
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package com.tot.count; B@6L<oZ
import java.util.*; g*LD}`X/-
/** 8 Zp^/43
* wD{c$TJ?{F
* @author pz)>y&_o
*/ _'L16@q
public class CountCache { 0%}*Zo(e+
public static LinkedList list=new LinkedList(); J>nBTY,_<
/** Creates a new instance of CountCache */ `JPkho
public CountCache() {} Vq{3:QBR
public static void add(CountBean cb){ $6D*G-*8
if(cb!=null){ (*Q:'2e
list.add(cb); %8xRT@Q
} |Nj6RB7
} MpZ\j
} Vr( Z;YO
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CountControl.java a@qc?
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/* udLI AV*
* CountThread.java 6j6;lNUc
* DU]KD%kl
* Created on 2007年1月1日, 下午4:57 qdv O>k3
* H, :]S-T
* To change this template, choose Tools | Options and locate the template under c>^(=52Q
* the Source Creation and Management node. Right-click the template and choose R(VOHFvW6
* Open. You can then make changes to the template in the Source Editor. 2ag8?#
*/ k>.8 lc\
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package com.tot.count; 0('ec60u
import tot.db.DBUtils; Q3&q%n|<
import java.sql.*; !8cV."~
/** ^V96lKt/
* j4!O,.!T
* @author 1,bE[_
*/ "2sk1
public class CountControl{ N8#j|yf
private static long lastExecuteTime=0;//上次更新时间 7dACbqba
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 pb)8?1O|s
/** Creates a new instance of CountThread */ (?JdiY/
public CountControl() {} Z
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public synchronized void executeUpdate(){ fC*cqc~{@
Connection conn=null; S**eI<QFSk
PreparedStatement ps=null; @v#P u_
try{ b7Z o~Z
conn = DBUtils.getConnection(); :Ez,GA k
conn.setAutoCommit(false); $#u'XyA
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); NId.TaXh
for(int i=0;i<CountCache.list.size();i++){ 5h6o}
CountBean cb=(CountBean)CountCache.list.getFirst(); h3k>WNT7
CountCache.list.removeFirst(); DHw)]WB M
ps.setInt(1, cb.getCountId()); G--X)h-
ps.executeUpdate();⑴ 15<? [`:6
//ps.addBatch();⑵ Y-YuY
} [p`5$\e
//int [] counts = ps.executeBatch();⑶ \'*M
}G
conn.commit(); K SOD(
}catch(Exception e){ y5m2u8+
e.printStackTrace(); l&qCgw
} finally{ _"yA1D0d_
try{ bD:0k.`
if(ps!=null) { L1/`/
ps.clearParameters(); l$/lbwi%
ps.close(); wL
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ps=null; A&~fw^HM
} TxP+?1t
}catch(SQLException e){} <L#d<lx
DBUtils.closeConnection(conn); }>u `8'2v
} H%>4z3n
} y@!o&,,mq
public long getLast(){ g)#{<#*2
return lastExecuteTime; 'Uf?-t*LT@
} {.{Wl,|7
public void run(){ |9c~kTjK
long now = System.currentTimeMillis(); #H>{>0q
if ((now - lastExecuteTime) > executeSep) { PKSfu++Z
//System.out.print("lastExecuteTime:"+lastExecuteTime); c8JW]A`9b)
//System.out.print(" now:"+now+"\n"); 4Qfsxg
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); t n5
lastExecuteTime=now; o"
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executeUpdate(); d)YlD]I
} 3 J04 $cD
else{ }:Z A)
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); \{lv~I
} Zg(Y$ h\
} vCaN [
} UGhEaKH~R
//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 [c
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类写好了,下面是在JSP中如下调用。 0Lxz?R x]<
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<% rXX>I;`&
CountBean cb=new CountBean(); D'#Q`H
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 1I9v`eT4
CountCache.add(cb); <GNLDpj
out.print(CountCache.list.size()+"<br>"); S v>6:y9?G
CountControl c=new CountControl(); k5.5$<< T
c.run(); "lL+Heq>V
out.print(CountCache.list.size()+"<br>"); -y+>^45
%>