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: ==d@0`
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CountBean.java O{"
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/* d9/YW#tm
* CountData.java !Pmv
* G[V?#7.
* Created on 2007年1月1日, 下午4:44 "D V.%7*^
* ?kvc`7>
* To change this template, choose Tools | Options and locate the template under ?cQ
* the Source Creation and Management node. Right-click the template and choose lW F=bz0
* Open. You can then make changes to the template in the Source Editor. gHS;RF9
*/ E&G_7->
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package com.tot.count; m<ZwbD
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/** =\IcUY,4
* eit>4xMu
* @author MYqxkhcLH1
*/ *.ffyBI*~
public class CountBean { #]`ejr:2O
private String countType; .F=15A
int countId; 8'+XR`g:ax
/** Creates a new instance of CountData */ Y4PU~l
public CountBean() {} Q7PqN1jTE
public void setCountType(String countTypes){ %;,D:Tv=&
this.countType=countTypes; $;<h<#_n;
} ; *G[3kk
public void setCountId(int countIds){ TI-#\v9
this.countId=countIds; XK:KWqW
} 2fc8w3
public String getCountType(){ wzAp`Zs2Dm
return countType; 7S<Z&1(
} ?3tR(H<
public int getCountId(){ MmOGt!}9A
return countId; !Xt=+aKN
} >c~~i-=
} =U3,P%
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CountCache.java xBGSj[1`i
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/* 9.5hQZ
* CountCache.java Hl&]r'bK
* >iP>v`J
* Created on 2007年1月1日, 下午5:01 i>bFQ1Rdx
* l7 D/]&
* To change this template, choose Tools | Options and locate the template under 8a{FxCBw
* the Source Creation and Management node. Right-click the template and choose o{\@7'G
* Open. You can then make changes to the template in the Source Editor. `nMHuv
*/ [!>2[bbl
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package com.tot.count; [.P~-6~
import java.util.*;
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/** tq9t(0EL
* [|~X~AO%
* @author Py 8o8* H
*/ n
}lav
public class CountCache { Ch
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public static LinkedList list=new LinkedList(); (mHFyEG
/** Creates a new instance of CountCache */ -W>zON|l
public CountCache() {} lkp!S3,
public static void add(CountBean cb){ r8C6bFYM
if(cb!=null){ xU1dy*-
list.add(cb); gDnG!i+
} #m9V)1"wB
} #'z\[^vp
} &..![,)w^!
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CountControl.java =Feavyx
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/* Zl"h-~31
* CountThread.java PpN+q:(
* WT(R =bLw
* Created on 2007年1月1日, 下午4:57 ^sH1YE}0
* =1n>vUW+J
* To change this template, choose Tools | Options and locate the template under &eY$(o-Hw
* the Source Creation and Management node. Right-click the template and choose kYs2AzS{d
* Open. You can then make changes to the template in the Source Editor. hmkcWr`
*/ <2y~7h:
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package com.tot.count; r jU $*+
import tot.db.DBUtils; _*Vq1D ]C
import java.sql.*; -GP+e`d
/** A"eT@
* 7w)#[^
* @author >FHTBh& Y
*/ c[ff|-<g
public class CountControl{ ZvNXfC3Ia
private static long lastExecuteTime=0;//上次更新时间 oq]KOj[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 gzzPPd,hd
/** Creates a new instance of CountThread */ c#9 zw[y-L
public CountControl() {} ^f!d8
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public synchronized void executeUpdate(){ cJ:BEe
Connection conn=null; =KT7ZSTV
PreparedStatement ps=null; r3Z-mJ$:
try{ :[(X!eP
conn = DBUtils.getConnection(); )2F:l0g
conn.setAutoCommit(false); k`
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); c<JJuG
for(int i=0;i<CountCache.list.size();i++){ ycw'>W3.*
CountBean cb=(CountBean)CountCache.list.getFirst(); Re<X~j5]
CountCache.list.removeFirst(); V6wYJ$]
ps.setInt(1, cb.getCountId()); $K<jmEC@<
ps.executeUpdate();⑴ $yaE!.Kc
//ps.addBatch();⑵ @c$mc
} e5fJN)+a
//int [] counts = ps.executeBatch();⑶ !l6B_[!@
conn.commit(); 9L:v$4{LU
}catch(Exception e){ e~rBV+f
e.printStackTrace(); uK(+WA
} finally{ & PHHacp
try{ \/K>Iv'$
if(ps!=null) { 40%p
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ps.clearParameters(); 9FK:lFGD
ps.close(); >1s:F5u"
ps=null; zZ-e2)1v
} >tP/"4c
}catch(SQLException e){} 7-e)V{A`w
DBUtils.closeConnection(conn); @zfeCxVOA
} R52q6y:<x
} r(vk2Qy
public long getLast(){ |hp_X>Uv'
return lastExecuteTime; O";r\Z
} j-
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public void run(){ $BH0W{S
long now = System.currentTimeMillis(); >)N,V;j
if ((now - lastExecuteTime) > executeSep) { L/nz95
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;p\rgam
//System.out.print(" now:"+now+"\n"); +<
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >R !^aJ
lastExecuteTime=now; D>*%zz|
executeUpdate(); y''? yr
} !h9 An
else{ 6xz&Qi7w
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); F w{8MQ2
} Zb2 B5(0
} `5 e#9@/e
} NqqLRgMOR'
//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 z8z U3?
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类写好了,下面是在JSP中如下调用。 (nda!^f_s
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<% ,PN>,hFL
CountBean cb=new CountBean(); ={maCYlE.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =Z-.4\ 3
CountCache.add(cb); i-E&Y*\^9H
out.print(CountCache.list.size()+"<br>"); )J#@L*
CountControl c=new CountControl(); 62vz 'b
c.run(); JI\u -+BE
out.print(CountCache.list.size()+"<br>"); vgE5(fJh
%>