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: XJ3p<
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CountBean.java &P@dx=6d
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/* b-+~D9U<
* CountData.java 0S%xm'|N
* z3bRV{{YqN
* Created on 2007年1月1日, 下午4:44 nN]GO}
* 1j!LK-
* To change this template, choose Tools | Options and locate the template under w I7iE4\vz
* the Source Creation and Management node. Right-click the template and choose l[AQyR1+/
* Open. You can then make changes to the template in the Source Editor. KS3>c7
*/ \Xr
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package com.tot.count; 5(+PIKCjC
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/** ? +q(,P@*
* Wz%b,!
* @author xRI7_8Jpyn
*/ 8?za&v
public class CountBean { C;UqLMrOI
private String countType; WP5QA8`3
int countId; 0eP ]
/** Creates a new instance of CountData */ 3hi0
public CountBean() {} #aeKK7[
public void setCountType(String countTypes){ 3!H&bOF
this.countType=countTypes; JdK'~-L
} _-M27^\vV
public void setCountId(int countIds){ S#^2k!(|G
this.countId=countIds; 0'3f^Ajf
} &&daQg4Ha
public String getCountType(){ nhu;e}[>
return countType; +}.~"
} vR)f'+_Nz
public int getCountId(){ s<XAH7?0
return countId; jv4O
} QH d^?H*
} F+m%PVW:
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CountCache.java 0|J]EsPxu
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/* A5\00O~
* CountCache.java `k.Tfdu)K
*
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* Created on 2007年1月1日, 下午5:01 aob+_9o
* nZbINhls
* To change this template, choose Tools | Options and locate the template under 'e(]woe
* the Source Creation and Management node. Right-click the template and choose T)Zef
* Open. You can then make changes to the template in the Source Editor. '
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*/ V`WSZ
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package com.tot.count; z]%c6ty
import java.util.*; I,lX;~xb
/** ^ 5D%)@~
* ..K@'*u
* @author Xt.ca,`U
*/ #hZ`r5GvTj
public class CountCache { E-`3}"{
public static LinkedList list=new LinkedList(); p=jpk@RX
/** Creates a new instance of CountCache */ #lY_XV.
public CountCache() {} li37*
public static void add(CountBean cb){ [pRRBMho
if(cb!=null){ mp:xR ^5c
list.add(cb); Ct<]('Hm(
} KL<,avC/
}
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} 0z
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CountControl.java \GD\N=?~
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/* k6$Ft.0d1Z
* CountThread.java RD|DHio%
* {44#<A<
* Created on 2007年1月1日, 下午4:57 `9*
|Y 8:
* ;Zy[2M
* To change this template, choose Tools | Options and locate the template under 6KRC_-
* the Source Creation and Management node. Right-click the template and choose PNs*+/-S
* Open. You can then make changes to the template in the Source Editor. II'"Nkxd
*/ LG+2?+tE"
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package com.tot.count; UasU/Q <
import tot.db.DBUtils; :Dj0W8V
import java.sql.*; !kS/Ei
/** |pG%]?A
* .nzN5FB
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* @author X5tx(}j
*/ srQGqE~
public class CountControl{ %xv*#.<Vj
private static long lastExecuteTime=0;//上次更新时间 eev-";c
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3`TD>6rs
/** Creates a new instance of CountThread */ )kT.3
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public CountControl() {} AnK~<9WQj
public synchronized void executeUpdate(){ 9vauCIfVC
Connection conn=null; ^m/7TwD
PreparedStatement ps=null; ^~;"$=Wf
try{ agkGUK/
conn = DBUtils.getConnection(); +^DDWVp
conn.setAutoCommit(false); QnA~,z/.w
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }n( ?|
for(int i=0;i<CountCache.list.size();i++){ ;Rljx3!N
CountBean cb=(CountBean)CountCache.list.getFirst(); {SkE`u4Sz
CountCache.list.removeFirst(); f#kT?!sP
ps.setInt(1, cb.getCountId()); !<3!ORFO
ps.executeUpdate();⑴ ri%j*Kn
//ps.addBatch();⑵ Am!OLGG4
} U38~m}c
//int [] counts = ps.executeBatch();⑶ =/!RQQ|8o
conn.commit(); !pZ<{|cH
}catch(Exception e){ FyQr$;r
e.printStackTrace(); |->CI
} finally{ RcC5_@W
try{ \^1S:z
if(ps!=null) { ox*>HkV
ps.clearParameters(); Ae[fW97
ps.close(); SLW|)Q24
ps=null; {2)).g
} h343$,))u
}catch(SQLException e){} Xp.$FJ1)
DBUtils.closeConnection(conn); w{*PZb4
} \(MIDCZ@-
} ^
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public long getLast(){ 9:P\)'y?
return lastExecuteTime; <L+1
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} MD^,"!A
public void run(){ (6Ciqf8
long now = System.currentTimeMillis(); I^Dm 3yz
if ((now - lastExecuteTime) > executeSep) { %:v<&^oDlm
//System.out.print("lastExecuteTime:"+lastExecuteTime); ?>Ngsp>-P
//System.out.print(" now:"+now+"\n"); 2?{'(iay
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); nTl2F1(sV7
lastExecuteTime=now; 6>]w1
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executeUpdate(); ;0U*N &
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} aaP6zJXi
else{ iB|htH'T
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); nV`U{}x
} DL<;qhte
} U&ytZ7iB
} #jh5% @
//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 THlQifA!
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类写好了,下面是在JSP中如下调用。 uM\5GK
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<% osl\j]U8
CountBean cb=new CountBean(); 2qot(Zs1i
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); K3Bw3j 9
CountCache.add(cb); d'"|Qg_'
out.print(CountCache.list.size()+"<br>"); wX5q=I
CountControl c=new CountControl(); d
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c.run(); dVUe!S`
out.print(CountCache.list.size()+"<br>"); W4,'?o
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