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: QL
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CountBean.java ALPZc:
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/* @_0XK)pW
* CountData.java [?_^Cy
* &Q 3!ty
* Created on 2007年1月1日, 下午4:44 F DXAe-|Q
* {QJJw}!#
* To change this template, choose Tools | Options and locate the template under td{$c6
* the Source Creation and Management node. Right-click the template and choose V\4'Hd
* Open. You can then make changes to the template in the Source Editor. wR\%tumk
*/ Z+FJ cvYx
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package com.tot.count; 9Yd<_B#
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/** U%m,:b6V
* 0<nk>o
* @author iCa#OQ
*/ "){"{~
public class CountBean { A"d=,?yE
private String countType; $,F1E VJ
int countId; 7'CdDB6&.
/** Creates a new instance of CountData */ THkg,*;:
public CountBean() {} }-! 0d*I
public void setCountType(String countTypes){ qgDd^0
this.countType=countTypes; t 8|i>(O
} HZ )z^K?1
public void setCountId(int countIds){ ;MR8E9
this.countId=countIds;
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} <U$x')W
public String getCountType(){ <Y9e n!3\
return countType; N-y[2]J90
} 7S}NV7
public int getCountId(){ g-Vxl|hR
return countId; d3<7t
} _-$(=`8|<{
} k_/*>lIZY
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CountCache.java ?sk{(UN]
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/* RG0kOw0
* CountCache.java -LhO
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* #;z;8q
* Created on 2007年1月1日, 下午5:01 /R!:l l2
* Jx!#y A;
* To change this template, choose Tools | Options and locate the template under YZMSiDv[e
* the Source Creation and Management node. Right-click the template and choose C[6}
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* Open. You can then make changes to the template in the Source Editor. BF
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*/ T]HeS(
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package com.tot.count; ~l+2Z4nV
import java.util.*; 9$$dSN\&
/** ]{s0/(EA
* o#fr5>h-w
* @author TkBHlTa"=
*/ x8
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public class CountCache { L
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public static LinkedList list=new LinkedList(); %68'+qz
/** Creates a new instance of CountCache */ I() =Ufs5z
public CountCache() {} O`K2mt\%
public static void add(CountBean cb){ Gh>&+UA'$1
if(cb!=null){ ,)@njC?J
list.add(cb); uGOED-@
} <hvs{}TS
} Ra)wlIx
} %<8`(Uu5
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CountControl.java rP|~d}+I
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/* Swa0TiT(
* CountThread.java 4Oo{\&(
* z?dd5.k
* Created on 2007年1月1日, 下午4:57 fG9 ;7KG
* @<(4J
* To change this template, choose Tools | Options and locate the template under G%iTL"6
* the Source Creation and Management node. Right-click the template and choose )Fon;/p
* Open. You can then make changes to the template in the Source Editor. =gNPS0H
*/ n&OM~Vs
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package com.tot.count; mX 3p
import tot.db.DBUtils; _Z7`tUS-j
import java.sql.*; t.y-b`v
/** 17$'r^t,S
* jaw&[f
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* @author o3]Lrzh
*/ f7YBhF
public class CountControl{ 50_[n$tqE
private static long lastExecuteTime=0;//上次更新时间 plL|Ubn
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ NNt
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public CountControl() {} &hEn3u
public synchronized void executeUpdate(){ &S,_Z/BS;
Connection conn=null; 0vETg'r
PreparedStatement ps=null; {ETM >
try{ Z_Wzm!:
conn = DBUtils.getConnection(); J3 `0i@
conn.setAutoCommit(false); :of(wZa3Q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); p8Z?R^$9H
for(int i=0;i<CountCache.list.size();i++){ |Dt_lQp#
CountBean cb=(CountBean)CountCache.list.getFirst(); sYjhQN=Y*
CountCache.list.removeFirst(); jr,N+K(@T
ps.setInt(1, cb.getCountId()); .G.WPVE
ps.executeUpdate();⑴ '2GnA ws^
//ps.addBatch();⑵ ^/_Yk.w
} /~MH]Gh
//int [] counts = ps.executeBatch();⑶ 4-~Z{#-
conn.commit(); &rG B58
}catch(Exception e){ KL9k9|!p
e.printStackTrace(); KL3Z(
} finally{ ? D
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try{ >H^#!eaqw
if(ps!=null) { e2f+Fv
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ps.clearParameters(); v3#,Z!
ps.close(); 8Qo'[+4;
ps=null; fuzB;Ea
} q`,%L1c4
}catch(SQLException e){} ;$WHTO(
DBUtils.closeConnection(conn); nl
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} D"J',YN$
} g5
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public long getLast(){ ]?pQu '-(
return lastExecuteTime; (`S^6-^
} M@#T`aS
public void run(){ 9.8%Iw
long now = System.currentTimeMillis(); 4qdoF_
if ((now - lastExecuteTime) > executeSep) { XEQTT D<
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;-6-DEL
//System.out.print(" now:"+now+"\n"); MjU|XQS:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); V(_1q
lastExecuteTime=now; B*N1)J\5
executeUpdate(); (J[Xryub
} lDTHK2f
else{ J91[w?,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,Cb3R|L8
} |~r-VV(=
} T5
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} tLBtE!J$[
//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 #obRr#8
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类写好了,下面是在JSP中如下调用。 @^xtxtjzux
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<% !bP%\)5
CountBean cb=new CountBean(); " !~o
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,;_+o]
CountCache.add(cb); )P$|9<_q7x
out.print(CountCache.list.size()+"<br>"); tO&ffZP8$
CountControl c=new CountControl(); 7Ml4u%?
c.run(); h:nybLw?
out.print(CountCache.list.size()+"<br>"); ikW[lefTq
%>