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: >I~z7JS
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CountBean.java dU3>h[q
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/* {bqKb=nyZ
* CountData.java x]cZm^
* fO!O"D5
* Created on 2007年1月1日, 下午4:44 UC/2&7?
* $!C+i"q$
* To change this template, choose Tools | Options and locate the template under cY'To<v
* the Source Creation and Management node. Right-click the template and choose 4,ynt&
* Open. You can then make changes to the template in the Source Editor. Ltd?#HP
*/ F>(#Af9
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package com.tot.count; YKOO(?lv
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/** ~<OjXuYu
* i/~QJ1C
* @author (ul-J4E\O
*/ %kFELtx
public class CountBean { 1y-lZ}s_
private String countType; CVG>[~}(9'
int countId; EFt`<qwj
/** Creates a new instance of CountData */ f<altz_\q
public CountBean() {} r tmt 3
public void setCountType(String countTypes){ k&iScMgCTH
this.countType=countTypes; 4{WV
} _Ge^
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public void setCountId(int countIds){ 5=h'!|iY
this.countId=countIds; 1$D`Z/N"A
} ;s.5\YZ"k
public String getCountType(){ yZ)aKwj%U
return countType; |abst&yp
} U3+_'"
public int getCountId(){ <i\zfa'6
return countId; 'Mx K}9
} 7r[%|:
} bNpIC/#0K
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CountCache.java 'S4EKV]
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/* n!eqzr{
* CountCache.java [aZ v?Z
* &DQ4=/Z
* Created on 2007年1月1日, 下午5:01 pkN:D+gS
* skDk/-*R
* To change this template, choose Tools | Options and locate the template under v&b.Q:h*'
* the Source Creation and Management node. Right-click the template and choose VFmg"^k5
* Open. You can then make changes to the template in the Source Editor. 2*q:
^
*/ 3 [)s;e
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package com.tot.count; KD"&_PX
import java.util.*; OWXye4`*
/** /.kna4k
* QJIItx4hE
* @author y(3c{y@~X
*/ Ma=6kX]
public class CountCache { }vUlTH
public static LinkedList list=new LinkedList(); q?-3^z%u
/** Creates a new instance of CountCache */ ncJFB,4
public CountCache() {} feI[M;7u
public static void add(CountBean cb){ Z~phOv
if(cb!=null){ FO(0D?PCR
list.add(cb); %6IlE.*,
} 7l#2,d4
} <\d|=>;
} $,e?X}4
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CountControl.java f{^M.G@
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/* teOBsFy/I
* CountThread.java "H="Ip!s
* x
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* Created on 2007年1月1日, 下午4:57 !`
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* 3q|cZQK!1
* To change this template, choose Tools | Options and locate the template under >4|c7z4
* the Source Creation and Management node. Right-click the template and choose lKV\1(`
* Open. You can then make changes to the template in the Source Editor. jq("D,
*/ ,v}?{pc
*L;pc g8{
package com.tot.count; Q%n{*py
import tot.db.DBUtils; +r-dr>&H@
import java.sql.*; Rg?{?qK\K
/** S\3AW,c]w
* #NN"(I
* @author G V:$;
*/ EAD0<I<>
public class CountControl{ y KYP
private static long lastExecuteTime=0;//上次更新时间 iIGI=EwZ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 $\,BpZ
}3
/** Creates a new instance of CountThread */ W`Q$t56
public CountControl() {} b$goF
}b'g
public synchronized void executeUpdate(){
};"+ O
Connection conn=null; 'Uko^R)(
PreparedStatement ps=null; zD)IU_GWa
try{ 2B9i R
conn = DBUtils.getConnection(); ovDJ{3L6O
conn.setAutoCommit(false); t8DL9RW'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); &>W (l.
for(int i=0;i<CountCache.list.size();i++){ fKTDt%
CountBean cb=(CountBean)CountCache.list.getFirst(); i+)}aA
CountCache.list.removeFirst(); 9QH9gdiw
ps.setInt(1, cb.getCountId()); +dCDM1{_a
ps.executeUpdate();⑴ xBL$]>
//ps.addBatch();⑵ b'7z DZI]
} |k`f/*
//int [] counts = ps.executeBatch();⑶ Z&dr0w8
conn.commit(); \o:ELa HY
}catch(Exception e){ ]{,Gf2v;;d
e.printStackTrace(); *^@#X-NG
} finally{ 5?5-;H
try{ wc7mJxJxA
if(ps!=null) { .0
s[{x
ps.clearParameters(); b46[fa
ps.close(); hgweNRTh!
ps=null; .# 6n
} JO2ZS6k[
}catch(SQLException e){} 7b&JX'`Mb
DBUtils.closeConnection(conn); #+K
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} )D["M$ZA^
} af<NMgT2s~
public long getLast(){ IpWy)B>Fl3
return lastExecuteTime; 4d^
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} SZ5O89
public void run(){ aNE9LAms
long now = System.currentTimeMillis(); PPoI>J
if ((now - lastExecuteTime) > executeSep) { G$;]
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//System.out.print("lastExecuteTime:"+lastExecuteTime); M5GY>3P$c
//System.out.print(" now:"+now+"\n"); t."g\;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); #`jE%ONC
lastExecuteTime=now; jl.okWuiY
executeUpdate();
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} bBUbw *DF)
else{ lAdDu
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1R=)17'O
} TL},Unq
} 0?lp/|K
} ~L %Pz0Gg
//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 M}Nb|V09
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类写好了,下面是在JSP中如下调用。 OUEI~b1
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<% 1Pk mg%+
CountBean cb=new CountBean(); iNod</+"K
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .FIt.XPzv
CountCache.add(cb); ?EI'^xg
out.print(CountCache.list.size()+"<br>"); op hH9D
CountControl c=new CountControl(); f._l105.
c.run(); =X-^YG3x
out.print(CountCache.list.size()+"<br>"); P?9nTG
%>