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: _G.!^+)kEm
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CountBean.java -Q?c'e
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/* ,2 W=/,5A
* CountData.java hmG8
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* 9Hb|$/FD
* Created on 2007年1月1日, 下午4:44 k4u/vn`&r
* Q{'4,J-w
* To change this template, choose Tools | Options and locate the template under >b5 ;I1o=y
* the Source Creation and Management node. Right-click the template and choose )uR_d=B&
* Open. You can then make changes to the template in the Source Editor. t?Qbi)T=z
*/ vx' ] ;
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package com.tot.count; }YM\IPsPu
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/**
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* %,
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* @author pYr+n9)^
*/ -U
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public class CountBean { x{K"z4xbI
private String countType; N81M9#,["~
int countId; $_TS]~y4}
/** Creates a new instance of CountData */ 0rI/$
public CountBean() {} :&'jh/vRN
public void setCountType(String countTypes){ enQW;N1_M
this.countType=countTypes; p9u'nDi
} )S`[ gK
public void setCountId(int countIds){ PeqW+Q.
this.countId=countIds; ^?sP[;8S!
} %eIaH!x:
public String getCountType(){ C8T0=o/-`
return countType; 3"v>y]$U
} -OU{99$aS
public int getCountId(){ _`^AgRE
return countId; .QZjJ9pvK
} chKEGosbF
} $ xHtI]T
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CountCache.java EU|IzUjFj|
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/* -@`Ah|m@}
* CountCache.java yZ)9Hd
* oD\t4]?E
* Created on 2007年1月1日, 下午5:01 `aG_ m/7|
* *)
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* To change this template, choose Tools | Options and locate the template under |#<z\u }
* the Source Creation and Management node. Right-click the template and choose 8Yf*vp>T/x
* Open. You can then make changes to the template in the Source Editor. sP2Uj
*/ |&W4Dkn
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package com.tot.count; 'bSWJ/;p)
import java.util.*; DQP!e6Of
/** hi/d%lNZ
* ~TS!5Wiv
* @author _&9P&Zf4
*/ dhnX\/
public class CountCache { #Y=b7|l
public static LinkedList list=new LinkedList(); Y`eF9Im,
/** Creates a new instance of CountCache */ c^pQitPv
public CountCache() {} oe|;>0yf
public static void add(CountBean cb){ 0,0Z!-Y
if(cb!=null){ r63l(
list.add(cb); ")vtS}Ekt
} (GpP=lSSeY
} @{_X@Wv4iV
} +>*=~R
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CountControl.java mTWd+mx
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/* f+s)A(?3
* CountThread.java }[UH1+`L
* _b-g^#L%
* Created on 2007年1月1日, 下午4:57 MD<x{7O12>
* w@Q~ax/
* To change this template, choose Tools | Options and locate the template under <8kCmuGlk
* the Source Creation and Management node. Right-click the template and choose 1hi,&h
* Open. You can then make changes to the template in the Source Editor. %$Py @g
*/ G/#<d-}_
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package com.tot.count; KGo^>us
import tot.db.DBUtils; ocK4Nxs
import java.sql.*; F*Hovxez
/** \ctzv``/n
* tKLeq(
* @author h?OSmzRLd
*/ O|=?!|`o
public class CountControl{ uE (5q!/
private static long lastExecuteTime=0;//上次更新时间 u?MhK#Mr
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 MmvOyKNZF
/** Creates a new instance of CountThread */ |ZifrkD=
public CountControl() {} c U(z5th
public synchronized void executeUpdate(){ .B2e$`s$
Connection conn=null; Pp69|lxV=k
PreparedStatement ps=null; &1^~G0Rh\
try{ CPcUB4a%#
conn = DBUtils.getConnection(); GeB&S!F
conn.setAutoCommit(false); _ eBNbO_J
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "a'I^B/
for(int i=0;i<CountCache.list.size();i++){ nXb_\9E
CountBean cb=(CountBean)CountCache.list.getFirst(); a`^$xOK,
CountCache.list.removeFirst(); sg}<()
ps.setInt(1, cb.getCountId()); 1EQ:@1
ps.executeUpdate();⑴ bDh4p]lm
//ps.addBatch();⑵ e@Ev']
} noa+h<vGb
//int [] counts = ps.executeBatch();⑶ +`Nu0y!rj
conn.commit(); Bd=K40Z:
}catch(Exception e){ G"u4]!$/
e.printStackTrace(); B= E/|J</
} finally{ I/A%3i=H
try{ dJ])`S
if(ps!=null) { 0k?]~f
ps.clearParameters(); <im}R9eJ1
ps.close(); #EE<MKka
ps=null; 6}c!>n['
} b 1Wz
}catch(SQLException e){} )y:))\>
DBUtils.closeConnection(conn); r<srTHGLo
} BOM0QskLf
} }.9a!/@Aj
public long getLast(){ G@jx&#v
return lastExecuteTime; D5bi)@G7z
} [`tNa Vg
public void run(){ Q$`uZ
long now = System.currentTimeMillis(); ;ud"1wH
if ((now - lastExecuteTime) > executeSep) { AOcUr)
//System.out.print("lastExecuteTime:"+lastExecuteTime); ]=xX_
//System.out.print(" now:"+now+"\n"); T9r6,yY
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .T(vGiU
lastExecuteTime=now; eA
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executeUpdate(); :ntAU2)H
} 7MJ\*+T|03
else{ '4~I%Z7L
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); MuzQz.C
} Rh
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} &%/T4$'+Y+
} })uyq_nz
//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 3bo
[34
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类写好了,下面是在JSP中如下调用。 (0_zp`)
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<% E|_8#xvb
CountBean cb=new CountBean(); yn(bW\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); I*cb\eU8Y
CountCache.add(cb); tr/.pw6
out.print(CountCache.list.size()+"<br>"); +tg${3ti_
CountControl c=new CountControl(); PX/^*
c.run(); y[S9b(:+
out.print(CountCache.list.size()+"<br>"); `}$bJCSF.n
%>