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: Q&d"uLsx
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CountBean.java {;0+N -U
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/* +_E\Omcw
* CountData.java %I
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* /A{/
* Created on 2007年1月1日, 下午4:44 ',g'Tl^E
* W.O]f.h
* To change this template, choose Tools | Options and locate the template under p\&Lbuzv
* the Source Creation and Management node. Right-click the template and choose c&rS7%
* Open. You can then make changes to the template in the Source Editor. _,C>+dv)
*/ ,^#{k!uaC{
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package com.tot.count; o[ua$+67E
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/** UOwEA9q%
* [$bK%W{f
* @author JPq2C\Ka
*/ 1[&V6=n
public class CountBean { "-U`E)]w*[
private String countType; D+u#!t[q
int countId; &P,z$H{o@
/** Creates a new instance of CountData */ /eI]!a
public CountBean() {} F CbU> 1R
public void setCountType(String countTypes){ m\];.Da
this.countType=countTypes; rCTH 5"
} rbEUq.Yk]~
public void setCountId(int countIds){ [IgB78_$
this.countId=countIds; c%bGVRhE
} MMYV8;c
public String getCountType(){ Y>l92=G
return countType; p!wx10b
} VYj*LiR
public int getCountId(){ ?;dfA/
return countId; 6_.K9;Gd
} U fzA/
} (r ]3tGp
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CountCache.java 6*({ZE
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}
/* av.L%l&d
* CountCache.java l\NVnXv:>
* '0juZ~>}
* Created on 2007年1月1日, 下午5:01 zxV,v*L)
* Y\sSW0ZX
* To change this template, choose Tools | Options and locate the template under 1lJY=`8qa
* the Source Creation and Management node. Right-click the template and choose IQ`#M~:
* Open. You can then make changes to the template in the Source Editor. :k"VR,riF
*/ -b7q)%V
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package com.tot.count; )U~,q>H+
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import java.util.*; Rpi@^~aPE
/** E[Rd=/P6
* xXJl Qbs
* @author 9AxeA2/X
*/ Tr}
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public class CountCache { S\F;b{S1
public static LinkedList list=new LinkedList(); BM@:=>ypQ
/** Creates a new instance of CountCache */ 6;:s N8M+1
public CountCache() {} m-M.F9R
public static void add(CountBean cb){ ,Qd;t
if(cb!=null){ _"Bh
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list.add(cb); _I&];WM\
} 9qHbV
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} CfSpwkg
} <ah!!
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CountControl.java KXAh0A?&+
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/* /hojm6MM
* CountThread.java /]mfI&l+9
* }AZ0BI,TI
* Created on 2007年1月1日, 下午4:57 ~BSIp
.
* 1236W+
* To change this template, choose Tools | Options and locate the template under 4FWb5b!A=
* the Source Creation and Management node. Right-click the template and choose )YB@6TiD
* Open. You can then make changes to the template in the Source Editor. %LH~Im=
*/ 4490l"
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package com.tot.count; ,:Q+>h
import tot.db.DBUtils; #LGAvFA*_F
import java.sql.*; y rSTU-5u
/** v*Fr#I0U
* .%.bIT
* @author zNu>25/)(
*/ ?gp:uxq,.
public class CountControl{ ,-C%+SC
private static long lastExecuteTime=0;//上次更新时间 Y[hTO.LF
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ifA)Ppt<`
/** Creates a new instance of CountThread */ W'>"E/Tx#O
public CountControl() {} 0 e}N{,&Y
public synchronized void executeUpdate(){ 3C+!Y#F
Connection conn=null; <6
LpsM}
PreparedStatement ps=null; iiWs]5
try{ D8`dEB2|S
conn = DBUtils.getConnection(); &2~c,] 9C
conn.setAutoCommit(false); z
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); XM9}ax
for(int i=0;i<CountCache.list.size();i++){ &!@7+'])
CountBean cb=(CountBean)CountCache.list.getFirst(); *Zj2*e{Z9U
CountCache.list.removeFirst(); $jpAnZR- /
ps.setInt(1, cb.getCountId()); =B0#z]qu
ps.executeUpdate();⑴ D 7D:?VoR
//ps.addBatch();⑵ h!vq~g
} [&tN(K9*
//int [] counts = ps.executeBatch();⑶ +"u6+[E
conn.commit(); J%Cn
}catch(Exception e){ =B+^-2G8
e.printStackTrace(); %\ifnIQ
} finally{ SuO@LroxTB
try{ &jg..R
if(ps!=null) { 5IwQ<V
ps.clearParameters(); a2'si}'3
ps.close(); 4Ou|4WjnL
ps=null; *dTI4k
} 1<Z~Gw4
}catch(SQLException e){} 9r5<A!1#L
DBUtils.closeConnection(conn); ^Yz.}a##w2
} %, Pwo{SH
} "JH
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public long getLast(){ Za*QX|
return lastExecuteTime; x#-+//
} M%\=Fb
public void run(){ */T.]^
long now = System.currentTimeMillis(); 4v=NmO}
if ((now - lastExecuteTime) > executeSep) { YH:murJMZ
//System.out.print("lastExecuteTime:"+lastExecuteTime); `4@_Y<
//System.out.print(" now:"+now+"\n"); e>OYJd0s
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); |uT&M`7\{
lastExecuteTime=now; eSC69mfD
executeUpdate(); 0~)_/yx?S
} @CxXkR
else{ }'"4q
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); $bGe1\
} T%opkyP>=
} bG'"l qn
} !6yyX}%o
//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 K|OowM4tv
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类写好了,下面是在JSP中如下调用。 M)<4|x
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<% pejG%pJ
CountBean cb=new CountBean(); &3o[^_Ti
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _:ORu Vk
CountCache.add(cb); e%B;8)7
out.print(CountCache.list.size()+"<br>"); ,.g9HO/R1
CountControl c=new CountControl(); zRz7*o&l
c.run(); @S-p[u
out.print(CountCache.list.size()+"<br>"); 8.g(&F
%>