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: rBNl%+ sB
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CountBean.java #a7 Wx}
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/* NlLgXn!
* CountData.java q]PeS~PjF\
* ;yd[QT<I<
* Created on 2007年1月1日, 下午4:44 x-W6W
* 1 /@lZ
* To change this template, choose Tools | Options and locate the template under :yPA6O 4
* the Source Creation and Management node. Right-click the template and choose uh,~CvXU]
* Open. You can then make changes to the template in the Source Editor. !{On_>`,
*/ 2AN6(k4o
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package com.tot.count; C8^=7HEB
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/** f~bZTf
* 2Mqac:L
* @author rID_^g_tP8
*/ ~n)gP9Hv
public class CountBean { a-nf5w>&q
private String countType; X MkyX&y
int countId; h5@v:4Jjo~
/** Creates a new instance of CountData */ /%O+]#$`0
public CountBean() {} -v]vm3Na
public void setCountType(String countTypes){ W=Y?_Oz
this.countType=countTypes; ChVur{jR
} %M?A>7b
public void setCountId(int countIds){ ]{2Eo
this.countId=countIds; &RSUB;ymL
} (<.uvq61
public String getCountType(){ MSef2|"P#
return countType; MqA%hlq
} G5;N#^myJ
public int getCountId(){ NhP&sQO
return countId; QtF'x<cB
} o>3g<-ul
} D4';QCwo
^
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CountCache.java I\8f`l
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/* &DUt`Dr w
* CountCache.java _dg2i|yP<
* _PI w""ssr
* Created on 2007年1月1日, 下午5:01 0zscOE{
* u0&
aw
* To change this template, choose Tools | Options and locate the template under cwe@W PE2
* the Source Creation and Management node. Right-click the template and choose f;Cu@z{b
* Open. You can then make changes to the template in the Source Editor. ,F4_ps?(
*/ =%wwepz6
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package com.tot.count; lDBn3U&z>
import java.util.*; n_8wYiBs(
/** ^+v6?%m
* GQU9UXe
* @author t&GjW6]W
*/ k@,&'imx
public class CountCache { xr }jw
public static LinkedList list=new LinkedList(); &s]wf
/** Creates a new instance of CountCache */ 3n\eCdV-b<
public CountCache() {} :yLSLN
public static void add(CountBean cb){ 8Gw0;Uu8D
if(cb!=null){ n$z}DE5 #
list.add(cb); 5)}3C_pmW
} q;XO1Se
} c5 jd
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} $U{\T4
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CountControl.java "cK@Yo
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/* 4{[cXM8*j
* CountThread.java n'dxa<F2|
* ]i}3`e?
* Created on 2007年1月1日, 下午4:57 ^t|CD|,K_O
* _~^JRC[q
* To change this template, choose Tools | Options and locate the template under Ym)8L.
* the Source Creation and Management node. Right-click the template and choose ]#UyYgPk
* Open. You can then make changes to the template in the Source Editor. 6$d3Ap@Gl
*/ #U46Au
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package com.tot.count; OZHQnvZ
import tot.db.DBUtils; 3Pb]Of#
import java.sql.*; K#O8P+n5[
/** L_3undy,
* ~|LlT^C
* @author h{&X`$
*/ D"5u N0Z
public class CountControl{ >bKN$,Qen
private static long lastExecuteTime=0;//上次更新时间 8z?q4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 D@M
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/** Creates a new instance of CountThread */ E7XFt#P.
public CountControl() {} r9x.c7=O
public synchronized void executeUpdate(){ Sdc
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Connection conn=null; ]cz*k/*0
PreparedStatement ps=null; hkSK;
try{ uC_&?
conn = DBUtils.getConnection(); mP1EWh|
conn.setAutoCommit(false); S 1%/ee3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2>E.Q@c
for(int i=0;i<CountCache.list.size();i++){ b*-g@S
CountBean cb=(CountBean)CountCache.list.getFirst(); a<Ru )Q?=
CountCache.list.removeFirst(); s|Hrb_[;l
ps.setInt(1, cb.getCountId()); C
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ps.executeUpdate();⑴ kc0YWW Q-:
//ps.addBatch();⑵ {=(GY@yU/
} yv.UNcP?
//int [] counts = ps.executeBatch();⑶ tMWDKatb
conn.commit(); m=Z1DJG
}catch(Exception e){ R7/"ye:7J
e.printStackTrace(); `iX~cUQ
} finally{ @KM !g,f
try{ @"`J~uK
if(ps!=null) { [")3c)OH|
ps.clearParameters(); MroJ!.9
ps.close(); B&l5yI
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ps=null; {x3"/sF
} )G7")I J/X
}catch(SQLException e){} 9-<EeV_/
DBUtils.closeConnection(conn); +V"t't7
} +="?[:
} Q4gsOxP
public long getLast(){ Up61Xn
return lastExecuteTime; -}l iG
} I}5#!s< {&
public void run(){ a$f$CjQ
long now = System.currentTimeMillis(); <&n\)R4C1
if ((now - lastExecuteTime) > executeSep) { 9{gY|2R_
//System.out.print("lastExecuteTime:"+lastExecuteTime); _Y7uM6HL\
//System.out.print(" now:"+now+"\n"); `"N56
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); \tLfB[S.5
lastExecuteTime=now; W'Wr8~{h
executeUpdate(); B~/:["zTh&
} gr\UI!]F
else{ 7*bUy)UZ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &E0d{2
} b'
1%g}
} OT6uAm+\7_
} &|;XLRHP}
//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 J2X;=X5
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类写好了,下面是在JSP中如下调用。 Wb*A};wE
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<% L&[uE;ro
CountBean cb=new CountBean(); 3P{
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); jf_xm=n
CountCache.add(cb); 3b1;f)t
out.print(CountCache.list.size()+"<br>"); +!dWQ=W
CountControl c=new CountControl(); 4Wz@^7|V5
c.run(); *]<M%q!<6
out.print(CountCache.list.size()+"<br>"); `)sC".b7
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