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: %cn<ych
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CountBean.java #'`{Qv0,
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/* vY3h3o
* CountData.java n@3>6_^rwT
* Q>z8IlJ}
* Created on 2007年1月1日, 下午4:44 y~V(aih}D
* *-X[u:
* To change this template, choose Tools | Options and locate the template under %BODkc Zh
* the Source Creation and Management node. Right-click the template and choose PA*5Bk="q
* Open. You can then make changes to the template in the Source Editor. "[N!m1i:{
*/ ;tf=gdX;
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package com.tot.count; lB4WKn=?Kl
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/** BA.uw_^4
* z$sGv19pB
* @author zQ PQ
*/ 1Y,Z
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public class CountBean { a+QpM*n7Lq
private String countType; !)$Zp\Sg
int countId; LP=)~K<
/** Creates a new instance of CountData */ /9X7A;O
public CountBean() {} ;.C\Ss<>*
public void setCountType(String countTypes){ D%Z|
this.countType=countTypes; U0+-W07>
} `D9$v(Ztr
public void setCountId(int countIds){ b,@/!ia
this.countId=countIds; 2an f$^[
} 2<3K3uz
public String getCountType(){ 7HWmCaa[
return countType; Bbc^FHip
} 7:@'B|
public int getCountId(){ mkpMfPt
return countId; 'GScszz
} $cgcX
} "N#Y gSr
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CountCache.java 4M T 7 `sr
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/* lquLT6]
* CountCache.java nt<]d\o0
* d-%hjy3N
* Created on 2007年1月1日, 下午5:01 Sjj6q`
* gM]:Ma
* To change this template, choose Tools | Options and locate the template under Y-9I3?ar
* the Source Creation and Management node. Right-click the template and choose MK*r+xfSae
* Open. You can then make changes to the template in the Source Editor. Q{/Ef[(a@
*/ TqQ[_RKg2
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package com.tot.count; Nboaf
import java.util.*; OTv)
/** \7_y%HR
* {RPI]DcO/
* @author V[V[~;Py
*/ iow"n$/
public class CountCache { Ul# r
public static LinkedList list=new LinkedList(); )%]J>&/0J
/** Creates a new instance of CountCache */ 3' 'me
public CountCache() {} IGgL7^MF
public static void add(CountBean cb){ ,: ^u-b|
if(cb!=null){ }0 ?3:A
list.add(cb); iDD$pd,e\
} x~sBzTa
} CGFDqCNr-
} #K&Gp-
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CountControl.java 'fW-Y!k%
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/* wM{s|Ay
* CountThread.java {h4E8.E
* tX[WH\(xI
* Created on 2007年1月1日, 下午4:57 bd`P0f?
* 9JwPSAo;
* To change this template, choose Tools | Options and locate the template under T4F/w|Q
* the Source Creation and Management node. Right-click the template and choose SfR%s8c`
* Open. You can then make changes to the template in the Source Editor. _dU\JD
*/ Xc.`-J~Il
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package com.tot.count; "jCu6Rj d
import tot.db.DBUtils; _dg\\c
import java.sql.*; WzWXE(
/** 8EY:tzw
* (%9$! v{3
* @author vD4*&|8T#
*/ 5R7DDJk
public class CountControl{ (5~h"s
private static long lastExecuteTime=0;//上次更新时间 lx i<F
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 R#KU^]"(
/** Creates a new instance of CountThread */ ULW~90
public CountControl() {} :KO2| v\
public synchronized void executeUpdate(){ Va8&Z
Connection conn=null; b Zt3|
PreparedStatement ps=null; n@w%Zl
try{ 9 $X-
conn = DBUtils.getConnection(); -qoH,4w
conn.setAutoCommit(false);
8Y?;x}
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); X?Au/
for(int i=0;i<CountCache.list.size();i++){ 'q.!|G2U
CountBean cb=(CountBean)CountCache.list.getFirst(); B<-Wea
CountCache.list.removeFirst(); (.,G=\!
ps.setInt(1, cb.getCountId()); Ca\6vR
ps.executeUpdate();⑴ ,?3G;-
//ps.addBatch();⑵ z{>Rc"%\
} GthYzd:'hJ
//int [] counts = ps.executeBatch();⑶ 8>V5dEbx'
conn.commit(); Ts9uL5i
}catch(Exception e){ I:.s_8mH}
e.printStackTrace(); %znc##j)q
} finally{ v,t:+
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try{ ]R *A
if(ps!=null) { @PU [:;
ps.clearParameters(); PW4q~rc=:
ps.close(); 0$njMnB2l
ps=null; SX*RP;vHy
} @|r{;'
}catch(SQLException e){} F}zDfY\-
DBUtils.closeConnection(conn); I_BJH'!t
} ~s{$WL&
} svSVG:48
public long getLast(){ f!"w5qC^
return lastExecuteTime;
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} g78^9Y*1
public void run(){ E.f%H(b
long now = System.currentTimeMillis(); Ep}s}Stlr}
if ((now - lastExecuteTime) > executeSep) { W8<%[-r
//System.out.print("lastExecuteTime:"+lastExecuteTime); %$mA03[MQ
//System.out.print(" now:"+now+"\n"); ZB{Em B0W
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); liSmjsk
lastExecuteTime=now; w>YDNOk
executeUpdate(); <uJ@:oWG7
} qWw=8Bq
else{ o(HbGHIP
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); j<x_ &1
} W%J\qA
} +v\oOBB)
} NO3/rJ6-
//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 j#6.Gq
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类写好了,下面是在JSP中如下调用。 e;jdqF~v!
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<% ME dWLFf
CountBean cb=new CountBean(); UI#h&j5pW
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); W4N{S.#!
CountCache.add(cb); F5Va+z,jg
out.print(CountCache.list.size()+"<br>"); j@9T.P1
CountControl c=new CountControl(); Q20%"&Xp]
c.run(); he4(hX^
out.print(CountCache.list.size()+"<br>"); Y0>y8UV
%>