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: TywK\hH
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CountBean.java t?HF-zQ
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/* FJ}gUs{m
* CountData.java -qfnUh
* lM$t!2pRB
* Created on 2007年1月1日, 下午4:44 >%l:Dw\A:
* oJh"@6u6K
* To change this template, choose Tools | Options and locate the template under D&-vq,c
* the Source Creation and Management node. Right-click the template and choose i+I0k~wY
* Open. You can then make changes to the template in the Source Editor. /~tP7<7A
*/ :s]\k%"
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package com.tot.count;
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/** ~pRs-
* j$mz3Yk
* @author %W&1`^Jl
*/ &*A:[b\
public class CountBean { 6`Lcs
private String countType; >O3IfS(l
int countId; V,vc_d?,_o
/** Creates a new instance of CountData */ z-I|h~ii
public CountBean() {} hVkO%]?
public void setCountType(String countTypes){ 8RU.}PD
this.countType=countTypes; =gs~\q
} `|,Bm|~:
public void setCountId(int countIds){ ~3d*b8
this.countId=countIds; g8'~e{=(
} `6}Yqh))
public String getCountType(){ 5#2jq<D
return countType; #Skj#)I"
} v1h.pbz`w
public int getCountId(){ DL1
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return countId;
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} Wt:~S/l
} +<{m45
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CountCache.java Cdmy.gx^
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/* KGD'mByt"
* CountCache.java [[X+P 0`r
* %mu>-h ac
* Created on 2007年1月1日, 下午5:01 MOeoU1Hn
* ZJvo9!DL|
* To change this template, choose Tools | Options and locate the template under h1*FPsc
* the Source Creation and Management node. Right-click the template and choose QvJZkGX
* Open. You can then make changes to the template in the Source Editor. =|"=l1
*/ w&5/Zh[~~L
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package com.tot.count; ]w-.|vx
import java.util.*; F 3s?&T)[G
/** DN<M?u]
* ?<6@^X"
* @author c$A@T~$
*/ j_V/GnEQ
public class CountCache { kP?_kMOx
public static LinkedList list=new LinkedList(); qlvwK&W<QM
/** Creates a new instance of CountCache */ {mf.!Xev
public CountCache() {} }^ ,q#'
public static void add(CountBean cb){ =JxFp,
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if(cb!=null){ kV+ R5R
list.add(cb); MyFCJJ/
} _ Mn6 L=
} }uiPvO+&p
} a
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CountControl.java V:>`*tlh
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/* \447]<u
* CountThread.java Yt*vqm[WV
* 4DM*^=9E
* Created on 2007年1月1日, 下午4:57 Yv=g^tw
* T%~SM5
* To change this template, choose Tools | Options and locate the template under A2BRbwr>
* the Source Creation and Management node. Right-click the template and choose 32^#RlSu8
* Open. You can then make changes to the template in the Source Editor. @,e8t BL
*/ #9,=Owup
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package com.tot.count; ~bGC/I;W>
import tot.db.DBUtils; %6HX*_Mr&
import java.sql.*; Cm410 =b
/** ,J&9kYz
* 7>&1nBh. f
* @author }LQ\a8]<
*/ $Elkhe]O %
public class CountControl{ R{`gR"*
private static long lastExecuteTime=0;//上次更新时间 QTE:K?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 dm& /K
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/** Creates a new instance of CountThread */ 3HKxYvc C
public CountControl() {} *IqVY&
public synchronized void executeUpdate(){ s`1^*Dl%+
Connection conn=null; /=/
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PreparedStatement ps=null; t)'dF*L
try{ .pW o >`"
conn = DBUtils.getConnection(); nALnB1
conn.setAutoCommit(false); qRl/Sl#F
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 4m\([EO
for(int i=0;i<CountCache.list.size();i++){ DJ|BM+
CountBean cb=(CountBean)CountCache.list.getFirst(); OfJd/D
CountCache.list.removeFirst(); jzMg'z/@J
ps.setInt(1, cb.getCountId()); v#F-<?Vv
ps.executeUpdate();⑴ 3a^)u-9,x
//ps.addBatch();⑵ mw"}8y
} }<&d]N
//int [] counts = ps.executeBatch();⑶ Khap9a_q-
conn.commit(); dQK`sLChv
}catch(Exception e){ f:XfAH3R{
e.printStackTrace(); 5zVQ;;9
} finally{ 0e\y~#-
try{ j/'
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if(ps!=null) { ;h9W\Se
ps.clearParameters(); z{/LX
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ps.close(); tvT4S
ps=null; B%mtp;) P
} D:)~%wu Lt
}catch(SQLException e){} OEI3eizgH
DBUtils.closeConnection(conn); XR+rT
} #<]Iz'\`
} Wp`C:H
public long getLast(){ 3C#RjA-2[
return lastExecuteTime; zQ<88E&&Xs
} 2NYi-@mr
public void run(){ "qE {a>d
long now = System.currentTimeMillis(); ,(;5%+#n
if ((now - lastExecuteTime) > executeSep) { %ZiK[e3G
//System.out.print("lastExecuteTime:"+lastExecuteTime); Q.1XP
//System.out.print(" now:"+now+"\n"); YuA7r"c
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^}@`!ON
lastExecuteTime=now; U3+A MVnB
executeUpdate(); Pt(tRH B
} #//
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else{ Z'e\_C
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); cyBW0wV1
} W} Zb~[,
} gwJ}]Tf
} (V)9s\Le_
//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 7IQqN&J
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类写好了,下面是在JSP中如下调用。 0mVuD\#=!
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<% 0Nt%YP
CountBean cb=new CountBean(); o6|"J%9GX
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ng
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CountCache.add(cb); PqI![KxZW
out.print(CountCache.list.size()+"<br>"); c&b/Joi7@
CountControl c=new CountControl(); :l;,m}#@
c.run(); 6&mWIk^VC
out.print(CountCache.list.size()+"<br>"); -F1P28<?
%>