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: 5zfaqt`
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CountBean.java 1S.nqOfx
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/* l)XzU&Sc~
* CountData.java xQaN\):^8
* r%_)7Wk*
* Created on 2007年1月1日, 下午4:44 8#7z5:_
* ]<z>YyBA
* To change this template, choose Tools | Options and locate the template under bhuA,}
* the Source Creation and Management node. Right-click the template and choose Nv #vfh9}P
* Open. You can then make changes to the template in the Source Editor. aQinR"o
*/ ,VJ0J!@
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package com.tot.count; bX5>qqB]
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/** --
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* M@8
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* @author mQJRq??P
*/ %3z-^#B=
public class CountBean { +XFF@h&=t
private String countType; f&{2G2O%
int countId; _?O'65
/** Creates a new instance of CountData */ XQlK}AK
public CountBean() {} |*OS;FD5
public void setCountType(String countTypes){ =3/||b4c
this.countType=countTypes; %4+r&
} P) GBuW
public void setCountId(int countIds){ _j<46^
this.countId=countIds; t[iE >
} >,32~C
public String getCountType(){ "{L%5:H@
return countType; "'II~/9
} }2V|B4
public int getCountId(){ 6^UeEmjc
return countId; $S=lm {
} ddlLS
} [^~Fu9+"
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CountCache.java EV2whs2g
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/* -4;{QB?
* CountCache.java BE}lzn=sF
* @ZD1HA,h"
* Created on 2007年1月1日, 下午5:01 8cR4@Hqx
* ykX}T6T
* To change this template, choose Tools | Options and locate the template under p4HX83y{
* the Source Creation and Management node. Right-click the template and choose LnrR#fF]Z
* Open. You can then make changes to the template in the Source Editor. QfT&y &
*/ 3V LwMF?
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package com.tot.count; 1&Nk
import java.util.*; ?<xGO@b
.
/** rc9 \
* Hz%#&E
* @author 2+
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*/ @6}c\z@AxM
public class CountCache { URX>(Y}g9^
public static LinkedList list=new LinkedList(); Q5{i#F7nJm
/** Creates a new instance of CountCache */ HrEZ]iQ@O0
public CountCache() {} &tHT6,Xv(
public static void add(CountBean cb){ 2syKYHV
if(cb!=null){ K=+w,H#`C
list.add(cb); 'hf-)\Ylf
} @M:j~
} lNls8@
} V5qvH"^
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CountControl.java mS&[<[x
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/* [[oX$0Fp\!
* CountThread.java Y'%sA~g
* M2%<4(UwI
* Created on 2007年1月1日, 下午4:57 [$OD+@~A2
* IAhyGD{b
* To change this template, choose Tools | Options and locate the template under h,rGa\X~0
* the Source Creation and Management node. Right-click the template and choose -"<H$
* Open. You can then make changes to the template in the Source Editor. _I3j7f,V
*/ .e"De-u
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package com.tot.count; J$j&j`
import tot.db.DBUtils; #O\4XZ,Lv
import java.sql.*; 3yZtyXRPn
/** P/,7CfyPd
* s80:.B
* @author `-qSvjX
*/ ,BOB &u
public class CountControl{ CNM/}|N^Si
private static long lastExecuteTime=0;//上次更新时间 }\OLBg/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 D>VI{p
/** Creates a new instance of CountThread */ ()}O|JL:K
public CountControl() {} #:DDx5%x<b
public synchronized void executeUpdate(){ mQ('X~l
Connection conn=null; m/cbRuPWgP
PreparedStatement ps=null; 8 y/YX
try{ ubj
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conn = DBUtils.getConnection(); s7D_fv4e
conn.setAutoCommit(false); M5: f^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); I8
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for(int i=0;i<CountCache.list.size();i++){ 2:&8FdU
CountBean cb=(CountBean)CountCache.list.getFirst(); MS_&;2
CountCache.list.removeFirst(); N@58R9P<p
ps.setInt(1, cb.getCountId()); J55K+
ps.executeUpdate();⑴ :BC0f9
//ps.addBatch();⑵ <@A/`3_O)
} 9'Pyo`hJ#U
//int [] counts = ps.executeBatch();⑶ Op~sR ^ez
conn.commit(); B.'@~$
}catch(Exception e){ />FrMz8;(
e.printStackTrace(); z%`Tf&UL
} finally{ JUF[Y^C
try{ G>YJ3p7
if(ps!=null) { )[~ #j6
ps.clearParameters(); !})/x~~e
ps.close(); vD[@cm
ps=null; i"F'n0*L
} C ])Q#!D|
}catch(SQLException e){} HP3~.1Sp
DBUtils.closeConnection(conn); (X)$8y
} y~SFlv36
} {iYu
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public long getLast(){ b+OLmd
return lastExecuteTime; gK-: t
} w>IkC+.?
public void run(){ >|o-&dk
long now = System.currentTimeMillis(); LJc
w->
if ((now - lastExecuteTime) > executeSep) { {,]BqFXv
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^t*+hFEI
//System.out.print(" now:"+now+"\n"); X']>b
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); nxsQDw\hy
lastExecuteTime=now; +&4PGv53J
executeUpdate(); bL)g+<:F
} 6!n"E@Bwu
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); xv$^%(Ujp
} #Vs/1y`()
} %,K |v
} Zv7@
//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 dsR{
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类写好了,下面是在JSP中如下调用。 c~5#)AXMT
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<% ~9kvC&/{[
CountBean cb=new CountBean(); yz9`1R2c
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {;n?c$r
CountCache.add(cb); bjm`u3
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out.print(CountCache.list.size()+"<br>"); r?{Vqephz
CountControl c=new CountControl(); 8kW9.
c.run(); :54|Z5h|
out.print(CountCache.list.size()+"<br>"); "sAR<5b
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