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: %1O;fQL
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CountBean.java #tZ4N7
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/* /G5d|P
* CountData.java |_`E1Y}}
* T-5nB>)
* Created on 2007年1月1日, 下午4:44 h&`e) a>+
* hg+X(0
* To change this template, choose Tools | Options and locate the template under :@ %4
* the Source Creation and Management node. Right-click the template and choose y>72{
* Open. You can then make changes to the template in the Source Editor. W0epAGrB
*/ Ys,{8Y,7
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package com.tot.count; /RHo1
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/** ZHGC6a!a
* IG|X!l
* @author Au4yBm
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*/ r41\r,`Dj
public class CountBean { ag*mG*Z
private String countType; I9:Cb)hbU]
int countId; l~6?kFy9h
/** Creates a new instance of CountData */ o'W5|Gy
public CountBean() {} uoHNn7 W
public void setCountType(String countTypes){ %,D<O,N
this.countType=countTypes; &jsVw)Ue
} 87=^J
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public void setCountId(int countIds){ y($%;l
this.countId=countIds; t%'Z<DmG+
} gF[z fDm
public String getCountType(){ ?pn}s]*/
return countType; SzUpWy&
} EmODBTu+
public int getCountId(){ hjIT_{mk
return countId; ve%
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} \8<BLmf4U
} Hm$=h>rY9[
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CountCache.java @6mBqcE'?
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/* xZ4~Oo@@_'
* CountCache.java ADpmvW f?
* du)~kU>l
* Created on 2007年1月1日, 下午5:01 .G+Pe'4a
* M@?xa/E64
* To change this template, choose Tools | Options and locate the template under M#~Cc~oT
* the Source Creation and Management node. Right-click the template and choose w:?oTuw
* Open. You can then make changes to the template in the Source Editor. 'bo~%WA]n
*/ X LL/4 )
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package com.tot.count; &2 `F n!m
import java.util.*; sFQ^2PwbS
/** Gi "941zVl
* (cN}Epi(D
* @author c05 %iv
*/ rk7QZVE
public class CountCache { IRn2|
public static LinkedList list=new LinkedList(); m< 3Ao^I+
/** Creates a new instance of CountCache */ d1U\ft:gV
public CountCache() {} -u?S=h}
public static void add(CountBean cb){ !!Aj<*%
if(cb!=null){ 3:8{"md@2
list.add(cb); #Sa27$&.>
} OtGb<v<_H
} nS&3?lx9_
} zxf"87se
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CountControl.java 'Er:a?88l
# *TEq
/* `;>= '"O!\
* CountThread.java 3bDQk
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* Fd#m<"
* Created on 2007年1月1日, 下午4:57 cOPB2\,
*
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* To change this template, choose Tools | Options and locate the template under Sr%;fq
* the Source Creation and Management node. Right-click the template and choose ap{2$k ,
* Open. You can then make changes to the template in the Source Editor. O9g{+e`
*/ PJ2qfYsH=>
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package com.tot.count; I('Un@hS
import tot.db.DBUtils; v>Mnl
import java.sql.*; $6CwkM:
/** 7^Ns&Q
* v{9t]s>B
* @author
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*/ vq!_^F<
public class CountControl{ 4E+hRKuo,
private static long lastExecuteTime=0;//上次更新时间 40|,*wi
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1}tbH[
/** Creates a new instance of CountThread */ om]4BRe
public CountControl() {} 5cEcTJL[C
public synchronized void executeUpdate(){ Y_]De3:V0B
Connection conn=null; ({NAMc*
PreparedStatement ps=null; kiRa+w:
try{ jS]><rm
conn = DBUtils.getConnection(); =IUUeFv +r
conn.setAutoCommit(false); _>v<(7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ND5`Q"k
for(int i=0;i<CountCache.list.size();i++){ c7M%xGrP
CountBean cb=(CountBean)CountCache.list.getFirst(); !w H'b
CountCache.list.removeFirst(); C#H:-Q&
ps.setInt(1, cb.getCountId()); i| ZceX/
ps.executeUpdate();⑴ mWyqG*-Hb
//ps.addBatch();⑵ #vzEu
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} !YP@m~
//int [] counts = ps.executeBatch();⑶ H_0/f8GwnG
conn.commit(); *FmTy|
}catch(Exception e){ |U_]vMq
e.printStackTrace(); IN,(yaC
} finally{ gq"gUaz
try{ Y;)dct
if(ps!=null) { ,9P:Draxs`
ps.clearParameters(); ixV0|P8,c
ps.close(); P|HKn,ar
ps=null; }=|!:kiE
} OQ,NOiNkap
}catch(SQLException e){} ?_v{|
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DBUtils.closeConnection(conn); aDehqP6vf
} @c~)W8
} y2+p1
public long getLast(){ ^mb[j`CCt
return lastExecuteTime; A.D{.a
} =+x yI
public void run(){ |,aG%MTL
long now = System.currentTimeMillis(); .cR
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if ((now - lastExecuteTime) > executeSep) { Y2O"]phi@
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;/0 Q1-
//System.out.print(" now:"+now+"\n"); !o>H1#2l
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); fPR$kch
lastExecuteTime=now; W$'R}L
executeUpdate(); [2dn\z28
} (E,Yo
else{ Raw)9tUt
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /'hC i]b@v
} \T;\XAGr
} (?H0+zws^
} &
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//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 nN~~cV
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类写好了,下面是在JSP中如下调用。 de]z T^&C
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<% t!2(7=P30(
CountBean cb=new CountBean(); iA,kX\nK
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); MgC:b-&5_
CountCache.add(cb); 9m-)Xdoy
out.print(CountCache.list.size()+"<br>"); 8v71e>
CountControl c=new CountControl(); 93<:RV
c.run(); LPwT^zV&N
out.print(CountCache.list.size()+"<br>"); {>"NyY
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