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: K`9ph"(Z
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CountBean.java W|PKcZ ]Uc
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/* 0wzq{~\{=_
* CountData.java S'I{'jP5
* }- Jw"|^W
* Created on 2007年1月1日, 下午4:44 ydNcbF%K
* mkCv
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* To change this template, choose Tools | Options and locate the template under nr#DE?
* the Source Creation and Management node. Right-click the template and choose kW#{[,7r
* Open. You can then make changes to the template in the Source Editor. K,>D%mJ
*/ ?5%|YsJP_
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package com.tot.count; 6[h3pb/m
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/** 0.^9)v*i
* WCbv5)uTUs
* @author !KUV,>L
*/ Di3<fp#w#
public class CountBean { 4No!`O-!&
private String countType; FZM9aA
int countId; 5"IbmD>D
/** Creates a new instance of CountData */ XeaO,P
public CountBean() {} !,*#e
public void setCountType(String countTypes){ .Qpqbp 8
this.countType=countTypes; HqW|
} T5eXcI0t
public void setCountId(int countIds){ Z7eD+4gD
this.countId=countIds; kpM5/=f/@
} ~ituPrH%<
public String getCountType(){ `};8
return countType; 5N:THvh6o
} L`yyn/2>
public int getCountId(){ y7I')}SC
return countId; |]5g+sd
} HR85!S`
} rurC! -
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CountCache.java pcM'j#;
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/* =H_|007C
* CountCache.java t(4%l4i;X
* OBF2?[V~
* Created on 2007年1月1日, 下午5:01 %bnDxCj"
* '"H'#%RU
* To change this template, choose Tools | Options and locate the template under QD0upYG
* the Source Creation and Management node. Right-click the template and choose Y&O<A8=8
* Open. You can then make changes to the template in the Source Editor. I9ga8mG4-'
*/ +"!,rZ7,A
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package com.tot.count; "YlN_U
import java.util.*; U@<>2
/** Ix,`lFbH
* N#')Qz:P
* @author Go}C{(4T
*/ I$4GM
public class CountCache { _LV;q! /j
public static LinkedList list=new LinkedList(); =Tf
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/** Creates a new instance of CountCache */ af]&3(33
public CountCache() {} *`:zSnu
public static void add(CountBean cb){ iPMI$
if(cb!=null){ T jO}P\p
list.add(cb); s4 o-*1R*`
} bJD2c\qoc
} TxYxB1C)
} VJM n5v[V
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CountControl.java Gw6*0&3')
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/* (]Z%&>*
* CountThread.java Vcg$H8m
* gqaENU>
* Created on 2007年1月1日, 下午4:57 P`HE3?r
* DWep5$>&K
* To change this template, choose Tools | Options and locate the template under .~0A*a
* the Source Creation and Management node. Right-click the template and choose (( 0%>HJ{~
* Open. You can then make changes to the template in the Source Editor. xp%,@]p
*/ mnM#NT5]
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package com.tot.count; )TxAhaz+
import tot.db.DBUtils; ~Dw.3P:-
import java.sql.*; CUB= T]
/** M3j_sd'N
* >3
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* @author !Y3w]_x[:
*/ J7BfH,o
public class CountControl{ ~S)o('
private static long lastExecuteTime=0;//上次更新时间 DCv~^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3&kHAXzM
/** Creates a new instance of CountThread */ y; Up@.IG
public CountControl() {} QDS=M]
public synchronized void executeUpdate(){ 6R1){,8
Connection conn=null; C6=7zYhR
PreparedStatement ps=null; F8km8lPQl
try{ Wyf+xr'Ky
conn = DBUtils.getConnection(); N5 SK_+
conn.setAutoCommit(false); AD4KoT&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); q9w6 6R
for(int i=0;i<CountCache.list.size();i++){ k#TonT
CountBean cb=(CountBean)CountCache.list.getFirst(); S,LW/:,
CountCache.list.removeFirst(); ,~t{Q*#_h
ps.setInt(1, cb.getCountId()); fr8:L!9
ps.executeUpdate();⑴ MoN;t;
//ps.addBatch();⑵ bZk7)b;1o
} RS G\3(
//int [] counts = ps.executeBatch();⑶ h>w4{ u0
conn.commit(); }tT"vCu
}catch(Exception e){ aDuO!?Cm
e.printStackTrace(); UUy|/z%
} finally{ }3cOZd_,t
try{ _"%ef"oPh
if(ps!=null) { yw`xK2(C$
ps.clearParameters(); |HXI4MU"
ps.close(); X62h7?'Pd
ps=null; 'u$e2^
} s4bLL
}catch(SQLException e){} T_O\L[]p*
DBUtils.closeConnection(conn); MV5'&" ,oB
} s{#ZRmc2B
} |:n4t6
public long getLast(){ FA?xp1E
return lastExecuteTime; w+bQpIPM
} 8
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public void run(){ pS
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long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { OwrzD~
//System.out.print("lastExecuteTime:"+lastExecuteTime); KFBo1^9N
//System.out.print(" now:"+now+"\n"); (Vglcj
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); =jjUwcl
lastExecuteTime=now; ,p/iN9+Z
executeUpdate(); Esw#D90q
} /j!?qID
else{ QA\eXnR
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2/f:VB?<T
} gT*0WgB
} P]-d(N}/H
} VZ{aET!
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 J')Dt]/9
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类写好了,下面是在JSP中如下调用。 &GcWv+p
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<% LX[J6YKR
CountBean cb=new CountBean(); EO$_]0yI;_
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $;Lb|~
CountCache.add(cb); Lz2 AWqR
out.print(CountCache.list.size()+"<br>"); &*RJh'o|N(
CountControl c=new CountControl(); - XIjol(
c.run(); @yPa9Ug(V
out.print(CountCache.list.size()+"<br>"); K~OfC
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