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: n>Y3hY
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CountBean.java t^&:45~Q
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/* n]}+ :
* CountData.java UIv TC
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* n4 KiC!*i0
* Created on 2007年1月1日, 下午4:44 -WB?hmx
* QBR9BR
* To change this template, choose Tools | Options and locate the template under )?%FU?2jrn
* the Source Creation and Management node. Right-click the template and choose R$K.;
* Open. You can then make changes to the template in the Source Editor. 7,!Mmu
*/ 9;&2LT7z
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package com.tot.count; R)I 8 )
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/** 82~UI'f \
* vPR1
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* @author MfJk`-%~
*/ Xf:CGR8_
public class CountBean { mbsdiab#N
private String countType; Gs7mO
int countId; Mw?nIIu(@
/** Creates a new instance of CountData */ C0jmjZ%w@
public CountBean() {} uwj/]#`
public void setCountType(String countTypes){ wHBkaPO!
this.countType=countTypes; a{L`C"rJ
} K-)*S\<}
public void setCountId(int countIds){ .hg<\-:_
this.countId=countIds; :u'X
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} +#6WORH0S
public String getCountType(){ Umm_FEU#]
return countType; %bt2^
} MKJ9PcVi
public int getCountId(){ pCb@4nb
return countId; 1#^[{XlAx
} Qf414 oW
} Nn
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CountCache.java TIW6v4
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/* BgA\l+
* CountCache.java 1HN_
* DOkEWqM!
* Created on 2007年1月1日, 下午5:01 }1`Rq?@J
* A~ '2ki5$g
* To change this template, choose Tools | Options and locate the template under l'W?X '
* the Source Creation and Management node. Right-click the template and choose 3SpDV'}
* Open. You can then make changes to the template in the Source Editor. mppBc-#EYr
*/ nOkX:5
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package com.tot.count; L-Xd3RCD
import java.util.*; iEr|?,
/** 7_S+/2}U*
* 5BS-q"
* @author <.l5>mgkCw
*/ Y3-Tg~/~W
public class CountCache { eoR@5OA&
public static LinkedList list=new LinkedList(); mZ/?uPIa
/** Creates a new instance of CountCache */ ,'Y*e[
public CountCache() {} 6"|PJ_@P
public static void add(CountBean cb){ |E53
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if(cb!=null){ !H~!i.m'-
list.add(cb); lDe9EJR
} 2N5N^S
} Cs^o- g!L
} HNY{%D
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CountControl.java (dpBGt@
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/* -njxc{b
* CountThread.java vO]gj/SaT
* ,T|iA/c
* Created on 2007年1月1日, 下午4:57 oFoG+H"&7\
* ~NpnRIt
* To change this template, choose Tools | Options and locate the template under Y;e@`.(
* the Source Creation and Management node. Right-click the template and choose ?b#/*T}ac
* Open. You can then make changes to the template in the Source Editor. pA4/'7nCl
*/ >7vSN<w~m
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package com.tot.count; ,PJl32
import tot.db.DBUtils; 5irewh'R
import java.sql.*; qI<*Cze
/** eY\tO"Hc
* /p<mD-:.M
* @author \Y>^L{
*/ I4m)5G?O2
public class CountControl{ 2}[rc%tV:?
private static long lastExecuteTime=0;//上次更新时间 d;D^<-[i
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 q1r\60M
/** Creates a new instance of CountThread */ tK g%5;v
public CountControl() {} /%=#*/E7
public synchronized void executeUpdate(){ Bpo~x2p
Connection conn=null; j[iJo
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PreparedStatement ps=null; U,RIr8 G
try{ Kl(}s{YFn.
conn = DBUtils.getConnection(); ]K XknEaxl
conn.setAutoCommit(false); 0 v/+%%4}
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); JR
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for(int i=0;i<CountCache.list.size();i++){ A
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CountBean cb=(CountBean)CountCache.list.getFirst(); OTN"XKa$
CountCache.list.removeFirst(); J-Sf9^G
ps.setInt(1, cb.getCountId()); '!yyg#
ps.executeUpdate();⑴ b2U[W#
//ps.addBatch();⑵ (niZN_qv
} 9^igzRn0
//int [] counts = ps.executeBatch();⑶ nqgfAQsE)
conn.commit(); u+(e,t
}catch(Exception e){ 3i>$g3G
e.printStackTrace(); b'3#FI=:
} finally{ MMhd -B1O&
try{ $N,9e
if(ps!=null) { 0<nKB}9
ps.clearParameters(); YX^{lD1Jj
ps.close(); q/Q^\HTk
ps=null; xS,):R
} wKk
}catch(SQLException e){} ZJy
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DBUtils.closeConnection(conn); _qE2r^o"B
} uBl&|yvxB
} b.YQN'
public long getLast(){ tHJ1MDw'
return lastExecuteTime; ot_jG)
} Qksw+ZjY#{
public void run(){ ;1(OC-2>d
long now = System.currentTimeMillis(); 8y|(]5
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if ((now - lastExecuteTime) > executeSep) { fQOaTsyA
//System.out.print("lastExecuteTime:"+lastExecuteTime); m6lNZb]
//System.out.print(" now:"+now+"\n"); JC>}(yQA
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1;? L:A
lastExecuteTime=now; I*K^,XY+
executeUpdate(); r)+dK}xl
} pC5-,Z;8
else{ `q$DNOrS
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [jAhw>
} cv#H
} JN|<R%hy
} o<V-gS
//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 g](m& O
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类写好了,下面是在JSP中如下调用。 2"BlV*\lS
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<% Hsp|<;Yg
CountBean cb=new CountBean(); Qf=%%5+?8
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Wz=ZhE9g
CountCache.add(cb); I]I5!\\ &[
out.print(CountCache.list.size()+"<br>"); 2GZUMXK
CountControl c=new CountControl(); HL 88
c.run(); m#8}!u&
out.print(CountCache.list.size()+"<br>"); Bu6t3
%>