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: &3Ry0?RET
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CountBean.java LFAefl\
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/* 4axuE]
* CountData.java c?*x2Vk
*
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* Created on 2007年1月1日, 下午4:44 mKJO?7tj
* q*!Vyk
* To change this template, choose Tools | Options and locate the template under 0.wNa~_G|
* the Source Creation and Management node. Right-click the template and choose CG
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* Open. You can then make changes to the template in the Source Editor. W'PW;.,
*/ ]u.)6{
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package com.tot.count; -I:L6ft8
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/** I@kMM12>c
* _D{{C
* @author Jq:Wt+a
*/ `j4OKZ
public class CountBean { [U,hb1Wi3
private String countType; m'KEN<)s
int countId; nTE\EZ+=2
/** Creates a new instance of CountData */ 3F9 dr@I.7
public CountBean() {} WtlLqD!_D
public void setCountType(String countTypes){ bSW~hyI w
this.countType=countTypes; x|*m ok
} / &em%/
public void setCountId(int countIds){ Z*Fn2I4
this.countId=countIds; Ny$N5/b!!
} +.a->SZ5"
public String getCountType(){ `^)oVs
return countType; 8aY}b($*ZI
} $e%m=@ga
public int getCountId(){ >&JS-jFg
return countId; L4<=,}KS
} =.IAd<C
} BO>[\!=y
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CountCache.java dW%;Z
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/* JD~]aoH
* CountCache.java loD:4e1
* Y+C6+I<3
* Created on 2007年1月1日, 下午5:01 +
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* RWZjD#5%Z
* To change this template, choose Tools | Options and locate the template under RaA7 U
* the Source Creation and Management node. Right-click the template and choose ~,{nBp9*
* Open. You can then make changes to the template in the Source Editor. 8*sP
*/ ej[Y
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package com.tot.count; X1="1{8H
import java.util.*; 5r^u7k
/** 7Pr5`#x#
* 5Y5N
* @author K>TvM&
*/ lmx'w
public class CountCache { ,Z(J; ~
public static LinkedList list=new LinkedList(); %`j2?rn
/** Creates a new instance of CountCache */ cKt8e^P
public CountCache() {} ]U.YbWe^
public static void add(CountBean cb){ G}`Hu_ [\)
if(cb!=null){ b@[\+P] "
list.add(cb); '.zr:l
} G:;(,
} ;CA7\&L>
} I z)~h>-F
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CountControl.java SA.,Q~_T7
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/* r%II`
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* CountThread.java 6}q# c
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* Created on 2007年1月1日, 下午4:57 Nk shJ2
* rY(^6[ !
* To change this template, choose Tools | Options and locate the template under oHx =Cg;
* the Source Creation and Management node. Right-click the template and choose ^4tz*i
* Open. You can then make changes to the template in the Source Editor. J,^e q@(
*/ lHSuT2)x;
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package com.tot.count; @Ke3kLQ_\X
import tot.db.DBUtils; `L
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import java.sql.*; G
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/** :_+Fe,h>|
* 1ogh8%
* @author [X=Ot#?u ~
*/ 3,{tGNl|
public class CountControl{ *M()z.N
private static long lastExecuteTime=0;//上次更新时间 G1:2MPH
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 R6dD17
/** Creates a new instance of CountThread */ 30$Q5]T
public CountControl() {} O$ ;:5zT
public synchronized void executeUpdate(){ 2~SjRIp Uw
Connection conn=null; vq*)2.
PreparedStatement ps=null; hh"=|c
try{ "K-2y^Dl
conn = DBUtils.getConnection(); yX;v
conn.setAutoCommit(false); B$%7U><'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); S t0AV.N1
for(int i=0;i<CountCache.list.size();i++){ *dm?,~f%<
CountBean cb=(CountBean)CountCache.list.getFirst(); "6fTZ<
CountCache.list.removeFirst(); :1\QM'O
ps.setInt(1, cb.getCountId()); KRh95B GU
ps.executeUpdate();⑴ qddP -uN
//ps.addBatch();⑵ ,-{2ai_
} ^ql+l~
//int [] counts = ps.executeBatch();⑶ IMay`us]:8
conn.commit(); / =2
}catch(Exception e){ 7ezf.[{R
e.printStackTrace(); @}@J$ g
} finally{ *$o{+YP
try{ D$
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if(ps!=null) { O8%Y .SK
ps.clearParameters(); VwV`tKit
ps.close(); wH Q$F(by
ps=null; =~~Y@eX
} E>3fk
}catch(SQLException e){} 1f^4J~{
DBUtils.closeConnection(conn); ?H_'L4Wv
} tJ,x>s?Y
} G(XI TL u*
public long getLast(){ s8]9OG3g
return lastExecuteTime; X#*|_(^
} Q1?G7g]N
public void run(){ .OC{,f+
long now = System.currentTimeMillis(); #]!0$z|Z
if ((now - lastExecuteTime) > executeSep) { vQpR0IEf]e
//System.out.print("lastExecuteTime:"+lastExecuteTime); =?/RaK/
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//System.out.print(" now:"+now+"\n"); aGY F\7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); DdL0MGwX
lastExecuteTime=now; ?E?dg#yk
executeUpdate();
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} N{<=s]I%x
else{ &[hq !v
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); PDnwaK
} }#/,nJm'
} -
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} P]@m0f
//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 0=r.I}x
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类写好了,下面是在JSP中如下调用。 &T8prE?
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<% @,63%
CountBean cb=new CountBean(); "gD)Uis
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !v2D 18(
CountCache.add(cb); yH8
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out.print(CountCache.list.size()+"<br>"); EQkv&k5X
CountControl c=new CountControl(); .`OdnLGy
c.run(); U.
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out.print(CountCache.list.size()+"<br>"); VR/>V7*7@
%>