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: ; :P4~R
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CountBean.java C#kE{Qw10r
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/* >>y`ap2%V
* CountData.java H<(F$7Q!\
* 68Fl/
* Created on 2007年1月1日, 下午4:44 j
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* 2DQVl
* To change this template, choose Tools | Options and locate the template under tk&AZb,sP
* the Source Creation and Management node. Right-click the template and choose \Ii{sn9
* Open. You can then make changes to the template in the Source Editor. _MBhwNBxZ
*/ {p +&Q|
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package com.tot.count; fg^AEn1i
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/** UK
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* ]n!V
* @author #\0m(v
*/ T/_u;My;
public class CountBean { Ti%MOYNCv
private String countType; D&G6^ME
int countId; .a.HaBBV
/** Creates a new instance of CountData */ rH3U;K!
public CountBean() {} c/|{yp$Ga>
public void setCountType(String countTypes){ !l (Vk
this.countType=countTypes; T$5wH )<
} (?jK|_
public void setCountId(int countIds){ 2~kx3` Q
this.countId=countIds; n<.7tr0f\
} aZN?V}^+
public String getCountType(){ FDMQLx f
return countType; 79T_9}M
} * Gg7(cnpw
public int getCountId(){ JQV%W+-@
return countId; \ 'm7un
} GV0\+A"vD
} |+Y-i4t
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CountCache.java j3Od7bBS]
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/* a*P v^Np-v
* CountCache.java \ND]x]5d
* \p4*Q}t
* Created on 2007年1月1日, 下午5:01 Dvg'
* C4mkt2Eb0a
* To change this template, choose Tools | Options and locate the template under gP%<<yl
* the Source Creation and Management node. Right-click the template and choose [V'c
* Open. You can then make changes to the template in the Source Editor. )Te\6qM
*/ JtFq/&{i
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package com.tot.count; 1)X|?ZD]F
import java.util.*; 7{#p'.nc5
/** @]Jq28
* E`)e
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* @author )s!A\a`vEd
*/ ,U{dqw8E{
public class CountCache { J67
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public static LinkedList list=new LinkedList(); F*k
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/** Creates a new instance of CountCache */ /TMVPnvz.
public CountCache() {} La ?A@SD
public static void add(CountBean cb){ |
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if(cb!=null){ iJ{axa &
list.add(cb); ]Jswxw
} (HAdr5
} ygz2bHpD~
} ~VsN\! G
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CountControl.java x1@,k=qrd
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/* MXA?rjd0
* CountThread.java OX;bA^+}P
* O60T.MM`
* Created on 2007年1月1日, 下午4:57 h% -=8l,
* JI@iT6.%IX
* To change this template, choose Tools | Options and locate the template under h4n~V:nNm
* the Source Creation and Management node. Right-click the template and choose *d8
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* Open. You can then make changes to the template in the Source Editor. C. .| O
*/ L1kn="5
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package com.tot.count; WI1YP0V
import tot.db.DBUtils; ]9QXQH
import java.sql.*; ;6V~yB
/** y;az&T
* q,[;AHb
* @author }R*%q
*/ l"J#Pvi
public class CountControl{ JAxzXAsAR
private static long lastExecuteTime=0;//上次更新时间 g3ukx$Q{>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 C^$E#|E9 N
/** Creates a new instance of CountThread */ )v(rEY
public CountControl() {} "-:H$
public synchronized void executeUpdate(){ rO}1E<g
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Connection conn=null; %p\~
PreparedStatement ps=null; Aw7N'0K9UN
try{ $?ss5:
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conn = DBUtils.getConnection(); ?8753{wk
conn.setAutoCommit(false); %g?M?D8Ud3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); v}!lx)#
for(int i=0;i<CountCache.list.size();i++){ %RW*gUvc]
CountBean cb=(CountBean)CountCache.list.getFirst(); (\qf>l+*
CountCache.list.removeFirst(); `@y~ JNf!
ps.setInt(1, cb.getCountId()); TFHYB9vV
ps.executeUpdate();⑴ @kSfF[4H
//ps.addBatch();⑵ .nY}_&
} K-'uE)
//int [] counts = ps.executeBatch();⑶ 4l0>['K&{
conn.commit(); W(62.3d~}?
}catch(Exception e){ -']Idn6
e.printStackTrace(); 3ko
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} finally{ 5B%KiE&p
try{ xZ'C(~t
if(ps!=null) { o"qxR'V
ps.clearParameters(); O=K0KOj
ps.close(); \>\ERVEd
ps=null; z&9ljQ
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} s58dHnj5+
}catch(SQLException e){} hrX/,D -c
DBUtils.closeConnection(conn); j~bNH~3
} `{ Ox=+]M
} 5Y;&L!T
public long getLast(){ <mJ8~
return lastExecuteTime; *lDVV,T'}w
} eJf]"-
public void run(){ 8A0a/
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long now = System.currentTimeMillis(); }#<Rs
if ((now - lastExecuteTime) > executeSep) { "7-}#_!g
//System.out.print("lastExecuteTime:"+lastExecuteTime); $mT)<N ;w
//System.out.print(" now:"+now+"\n"); /pRv
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .8'c
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lastExecuteTime=now; -I4@6vE,
executeUpdate(); (e;/Smol
} -V2f.QE%
else{ bRggt6$z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 5ms]Wbh)
} +L=Xc^
} 44 8%yP
} \hBzQ%0
//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 y.(<
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类写好了,下面是在JSP中如下调用。 InL_JobE8r
SP<(24zdd
<% IPTFx
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CountBean cb=new CountBean(); `#ff`j|a
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); B3yTN6-
CountCache.add(cb); GsO(\hR6^
out.print(CountCache.list.size()+"<br>"); Z6b]EcP)#
CountControl c=new CountControl(); pcIS}+L
c.run(); }x#e.}hf&
out.print(CountCache.list.size()+"<br>"); JS03BItt
%>