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: \'nE{
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CountBean.java vRO`hGH
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/* xSjs+Y;Mu
* CountData.java X*:)]p(R
* -.vNb!=
* Created on 2007年1月1日, 下午4:44 PF;`mdi-,
* xx%*85 <
* To change this template, choose Tools | Options and locate the template under DTx>^<Tk
* the Source Creation and Management node. Right-click the template and choose N8]d0
* Open. You can then make changes to the template in the Source Editor. XZPq4(,9}
*/ *wz6 2p
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package com.tot.count; |F>'7JJJ
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/** e&="5.ik
* ^(yU)k3pu
* @author mv9@Az9
*/ =)XC"kUp
public class CountBean { ("@ih]zYf
private String countType; p4wXsOQ}
int countId; k%ckV`y
/** Creates a new instance of CountData */ V8J!8=2
public CountBean() {} kR(hUc1O
public void setCountType(String countTypes){ ob>2SU[Y
this.countType=countTypes; Sc$]ar]S
} r;&rc:?A
public void setCountId(int countIds){ [,p[%Dza
this.countId=countIds; sBu- \P#
} 'd=B{7k@
public String getCountType(){ rc]`PV
return countType; u+vUv~4A6
} mmgIV&P
public int getCountId(){ &]H Y:
return countId; D7b]
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} /=ro$@
} FFqqAT5
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CountCache.java pWXoJ0N
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/* 4o*wLCo7^
* CountCache.java Ny)!uqul*
* go$zi5{h#
* Created on 2007年1月1日, 下午5:01 D[ (A`!)
* ;3WVrYe
* To change this template, choose Tools | Options and locate the template under (Puag*
* the Source Creation and Management node. Right-click the template and choose Ce1^S[
* Open. You can then make changes to the template in the Source Editor. }zu?SZH
*/ Qf}b3WEAI
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package com.tot.count; r@Tq-o
import java.util.*; x0_$,Tz@
/** Vi1=
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* OfGMeN6
* @author E%6}p++
*/ -*Z;EA-
public class CountCache { bjEm=4FI;
public static LinkedList list=new LinkedList(); zDO`w0N
/** Creates a new instance of CountCache */ @'{m-?*
public CountCache() {} }_L,Xg:I
public static void add(CountBean cb){ Fv"jKZPgzz
if(cb!=null){ V/}g'_E
list.add(cb); ?4,e?S6,[
} N
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} (:]on^|
} oO8V0VE\
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CountControl.java PYp<eo\
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/* |+Fko8-
* CountThread.java Cj x(Z]
* Wq1%
* Created on 2007年1月1日, 下午4:57 #4e Taik
* 4 <`'?
* To change this template, choose Tools | Options and locate the template under Gn_rf"
* the Source Creation and Management node. Right-click the template and choose LD~/*
* Open. You can then make changes to the template in the Source Editor. g~JN"ap
*/ as?~N/}
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package com.tot.count; pIy+3&\e;
import tot.db.DBUtils; G'sEbw'[
import java.sql.*; & A%*sD6
/** 2Po e-=
*
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* @author nDvj*lZF
*/ prx)Cfv
public class CountControl{ kFlq@['U
private static long lastExecuteTime=0;//上次更新时间 MwN.Ll
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,dM}B-
/** Creates a new instance of CountThread */ 7]w]i5
public CountControl() {} QVVR_1Q
public synchronized void executeUpdate(){ D/1f>sl
Connection conn=null; ? LA>5
PreparedStatement ps=null; WZa?Xb
try{ &xG>"sJ
conn = DBUtils.getConnection(); 451TTqc
conn.setAutoCommit(false); WML%yO\.;
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); kCWaji_x%
for(int i=0;i<CountCache.list.size();i++){ {uQp$`
CountBean cb=(CountBean)CountCache.list.getFirst(); \/Z?QBFvz
CountCache.list.removeFirst(); cZ{-h
ps.setInt(1, cb.getCountId()); T(E$0a)#
ps.executeUpdate();⑴ n9}3>~ll
//ps.addBatch();⑵ JlZU31Xws
} 0T{Z'3^=
//int [] counts = ps.executeBatch();⑶ E{m\LUd^
:
conn.commit(); J1Ay^*qRU
}catch(Exception e){ ahno$[
e.printStackTrace(); jW^@lH
EU
} finally{ tw/~z2G
try{ _<`j?$P
if(ps!=null) { [YQVZBT|{
ps.clearParameters(); y Q_lJIX
ps.close(); f,ajo
ps=null; Ps@a@d"83
} )zzK\I6/EQ
}catch(SQLException e){} F aOfe] F
DBUtils.closeConnection(conn); mT@8(
} %.
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} '$@bTW
public long getLast(){ G(2(-x"+
return lastExecuteTime; o/grM+_
} 3_:J`xX(4
public void run(){ +}al_.
long now = System.currentTimeMillis(); |#p`mc%f~\
if ((now - lastExecuteTime) > executeSep) { {G:dhi
//System.out.print("lastExecuteTime:"+lastExecuteTime); dD
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//System.out.print(" now:"+now+"\n"); ^gY^I`"e6
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); %jgB;Y
lastExecuteTime=now; h/7m.p]
executeUpdate(); Bg"KNg
} Fc{X$hh<
else{ 6 XZF8W
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); K'6dlwn).
} r~&[Gaw
} z@Klj qN
} &Ff#E?Y4|
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 21b
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类写好了,下面是在JSP中如下调用。 owz6j:
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<%
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CountBean cb=new CountBean(); E;Akm':
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _O76Aw-@l
CountCache.add(cb); h[|c?\E
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out.print(CountCache.list.size()+"<br>"); U}w,$
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CountControl c=new CountControl(); N,Fmu
c.run(); n]?KDID;
out.print(CountCache.list.size()+"<br>"); k
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