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: HKC&grp
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CountBean.java Q*f0YjH!
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/* xgsEe3|
* CountData.java /+<G@+(
* T7Y+ WfYh
* Created on 2007年1月1日, 下午4:44 $|@-u0sv
* ;iN[du
* To change this template, choose Tools | Options and locate the template under 1yS:`
* the Source Creation and Management node. Right-click the template and choose X2 <fS~m
* Open. You can then make changes to the template in the Source Editor. *\0h^^|@
*/ /*6[Itm_h
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package com.tot.count; ihct~y-9W
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/** !6 kn>447Y
* 3z k},8fu
* @author H-%
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*/ WxJaE;`Ige
public class CountBean { L 'e|D=y
private String countType; Lq#!}QcW=
int countId; 'O
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/** Creates a new instance of CountData */ ws;|fY
public CountBean() {} a0k/R<4
public void setCountType(String countTypes){ q:wz!~(>
this.countType=countTypes; (AG((eV
} &jrc]
public void setCountId(int countIds){ #A~7rH%hi
this.countId=countIds; 5sB~.z@
} nx!+:P ,
public String getCountType(){ T#}"?A|
return countType; GG4FS
} NiVZ=wEp,
public int getCountId(){ 5z.Y}
return countId; a3[,3
} Eh *u6K)Z
} \h}sA
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CountCache.java d(vt0
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/* =+4om*
* CountCache.java CE4Kc33OU|
* 1_mqPMm
* Created on 2007年1月1日, 下午5:01 WuQ;Da0+_F
* |QyZ:`0u
* To change this template, choose Tools | Options and locate the template under h.xtkD)Y~
* the Source Creation and Management node. Right-click the template and choose rj29$d?Y9
* Open. You can then make changes to the template in the Source Editor. rLp0)Go
*/ ~kI$8oAry
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package com.tot.count; YCG$GD
import java.util.*; a!&<jM
/** 0|mCk
* BtF7P}:MGf
* @author !#4b#l(e6
*/ 1#XZVp;M
public class CountCache { CSzu$Hnq
public static LinkedList list=new LinkedList(); -c[fg+L9
/** Creates a new instance of CountCache */ ! ^aJS'aq
public CountCache() {} cmp@Ow"c
public static void add(CountBean cb){ Vzh\1cF
if(cb!=null){ o#-^Lg&
list.add(cb); F>k/;@d
} 4SIS#m
} ^aqBL
} +@+*sVb
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CountControl.java gZL,xX
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/* VP }To
* CountThread.java A ?[Wfq|
* [n$6T
* Created on 2007年1月1日, 下午4:57 &3 x
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* K*tomy
* To change this template, choose Tools | Options and locate the template under ,UxAHCR~9
* the Source Creation and Management node. Right-click the template and choose *3(mNpi{_
* Open. You can then make changes to the template in the Source Editor. T?*f}J
*/ riSgb=7q9
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package com.tot.count; lG`%4}1
import tot.db.DBUtils; 3oPyh $*
import java.sql.*; g7v(g?
/** /kqa|=-`q
* xH>j
* @author 4@9xq<<5
*/ eY`o=xN
public class CountControl{ Hw,@oOh.
private static long lastExecuteTime=0;//上次更新时间 l-8rCaq&J
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 pE{Ecrc3|
/** Creates a new instance of CountThread */ B#o6UO\
public CountControl() {} $g
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public synchronized void executeUpdate(){ :;w#l"e7<
Connection conn=null; Eu[/* t+l
PreparedStatement ps=null; 4
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try{ qy/t<2'
conn = DBUtils.getConnection(); Wfsd$kN6{
conn.setAutoCommit(false); |u#7@&N1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Z)<lPg!YAR
for(int i=0;i<CountCache.list.size();i++){ &[5pR60
CountBean cb=(CountBean)CountCache.list.getFirst(); O&@CT] )8
CountCache.list.removeFirst(); ,3Aiz|v-
ps.setInt(1, cb.getCountId()); scy_
ps.executeUpdate();⑴ CWSc #E
//ps.addBatch();⑵ Bm+Ca:p%
} ,Y7QmbX^
//int [] counts = ps.executeBatch();⑶ 5jsZJpk$
conn.commit(); wB"`lY
}catch(Exception e){ C/q!!
e.printStackTrace(); 3 ]pHc)p!.
} finally{ [G"Va_A8
try{ `ix&j8E22w
if(ps!=null) { pL,l
ps.clearParameters(); A(+%DZ
ps.close(); aqv'c
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ps=null; 7Q?^wx
} Yb%#\.M/y
}catch(SQLException e){} ,hE989x<iI
DBUtils.closeConnection(conn); _>4)q=
} U,Fyi6{~
} @el
public long getLast(){ pz]!T'
return lastExecuteTime; YVPLHwh/5
} 6K^O.VoV^J
public void run(){ wQ81wfr1:
long now = System.currentTimeMillis(); OU<v9`<
if ((now - lastExecuteTime) > executeSep) { @DSKa`
//System.out.print("lastExecuteTime:"+lastExecuteTime); !1/F71l DX
//System.out.print(" now:"+now+"\n"); +9B .}t#
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]l,,en5V
lastExecuteTime=now; f'TEua_`
executeUpdate(); v4F+^0?
} P7$/yBI U
else{ `7R-2
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); b8glZb*$
} gKtgW&PYm
} I5ZM U
} U+&Eps&NI
//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 "NTiQ}i
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类写好了,下面是在JSP中如下调用。 "6Z(0 iu:{
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<% /|isRh|
CountBean cb=new CountBean(); 7 4]qz,
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); s%1ZraMvJ
CountCache.add(cb); *NC@o*
out.print(CountCache.list.size()+"<br>"); -\2hSIXj
CountControl c=new CountControl(); e(Rbq8D
c.run(); %a!gN
out.print(CountCache.list.size()+"<br>"); %Rk DR
%>