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: qRaPh:Q'
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CountBean.java S!PG7hK2
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/* L*4"D4V
* CountData.java AM=> P7
* k6"(\d9o
* Created on 2007年1月1日, 下午4:44 Pm6U:RL
* R +@|#!
* To change this template, choose Tools | Options and locate the template under MhA4C 8
* the Source Creation and Management node. Right-click the template and choose 8o+:|V~X
* Open. You can then make changes to the template in the Source Editor. "Bwz
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*/ &Z>??|f
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package com.tot.count; <pV8
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/** p>eYi \'
* Sed8Q-m
* @author d BB?A~
*/ qqo#H O
public class CountBean { p@O Ip
private String countType; z2{y<a9;?
int countId; mKu,7nMvF
/** Creates a new instance of CountData */ -BP10-V
public CountBean() {} Ms +ekY)
public void setCountType(String countTypes){ $1 B?@~&
this.countType=countTypes; md<^x(h"<
} 6O,k! y>
public void setCountId(int countIds){ #w%-IhP
this.countId=countIds; V|@bITJ?7
} x-c5iahp'
public String getCountType(){ L4B/
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return countType; E`.hM}h
} . q
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public int getCountId(){ 31c*^ZE.
return countId; U2?R&c;b
} [-[59H[6)
} [K,P)V>K
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CountCache.java ;o'r@4^&$R
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/* 5.ab/uk;M
* CountCache.java QY4;qA
* &k,DAx`rN;
* Created on 2007年1月1日, 下午5:01 ECi;o1hda
* 7w2$?k',-
* To change this template, choose Tools | Options and locate the template under 1OExa<Zq
* the Source Creation and Management node. Right-click the template and choose cH*")oD
* Open. You can then make changes to the template in the Source Editor. '*L6@e#U
*/ LI@BB:)[
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package com.tot.count; .]h/M,xg
import java.util.*; G=[<KtWa
/** f6K.F
* ,ja!OZ0$
* @author awo'#Y2>
*/ OnE%D|Tq=
public class CountCache { BFw_T3}zn
public static LinkedList list=new LinkedList(); $365VTh"
/** Creates a new instance of CountCache */ aL[6}U0 (}
public CountCache() {} w!H(zjv&(
public static void add(CountBean cb){ {|>Wwa2e
if(cb!=null){ q\?p' i
list.add(cb); VQqBo~
} &kzysv-_
} 8Yk*$RR9
} r@C~_LgL)
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CountControl.java ^wWbW&<Tg
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/* Le?g,c
* CountThread.java 8cOft ;|qB
* FfM^2`xP
* Created on 2007年1月1日, 下午4:57 gZ^Qt.6Z
* {aUTTEu
* To change this template, choose Tools | Options and locate the template under -GFZFi
* the Source Creation and Management node. Right-click the template and choose CnL=s6XD'
* Open. You can then make changes to the template in the Source Editor. p,8~)ic_
*/ YhV<.2^k
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package com.tot.count; I[k"I(
import tot.db.DBUtils; xrvM}Il
import java.sql.*; 1Zn8CmE V
/** \AroSy9
* bD ,X.
* @author Jf?6y~X>Y
*/ g=4^u*
public class CountControl{ }ww/e\|Nt=
private static long lastExecuteTime=0;//上次更新时间 R]X 0D.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AcuF0KWw/
/** Creates a new instance of CountThread */ "."(<c/3
public CountControl() {} 0)Ephsw
public synchronized void executeUpdate(){ !Nx1I
Connection conn=null; SC~k4&xy
PreparedStatement ps=null; HQ-++;Q
try{ ~>(~2083*;
conn = DBUtils.getConnection(); :K^J bQ
conn.setAutoCommit(false); %\<b{x# G
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); u|t l@_
for(int i=0;i<CountCache.list.size();i++){ a)ry}E =f
CountBean cb=(CountBean)CountCache.list.getFirst(); 0pMN@Cz6
CountCache.list.removeFirst(); -:ucp2
ps.setInt(1, cb.getCountId()); ]S&ki}i&
ps.executeUpdate();⑴ <r:AJ;
//ps.addBatch();⑵ @p*)^D6E\
} 0i_:J
//int [] counts = ps.executeBatch();⑶ [o#% Eg;
conn.commit(); DO80HS3ZD
}catch(Exception e){ fYUV[Gm
e.printStackTrace(); W#<1504ip
} finally{ &kIeW;X
try{ '3672wF/
if(ps!=null) { V+Tv:a
ps.clearParameters(); 7v%c.
ps.close(); ac l<dY6
ps=null; )6)bI.BY
} pjFO0h_Y
}catch(SQLException e){} vv
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DBUtils.closeConnection(conn); ;_(f(8BO
} +>q#eUS)
} Vbl-Ff
public long getLast(){ g.Xk6"kO
return lastExecuteTime; %)r ~GCd
} oa:YAqT
public void run(){ /J#(8p
long now = System.currentTimeMillis(); \A[l(aB
if ((now - lastExecuteTime) > executeSep) { xrkl)7;
//System.out.print("lastExecuteTime:"+lastExecuteTime); hX{,P:d=f
//System.out.print(" now:"+now+"\n"); w2nReB z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); \2s`mCY
lastExecuteTime=now; [Iks8ZWr_
executeUpdate(); "OjAhKfG
} *XTd9E^tXq
else{ 0y9 b0G
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); KRaL+A
} LQR2T5S/Q,
} 4qie&:4j
} ZkbE&7Z
//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 8v;^jo>ug
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类写好了,下面是在JSP中如下调用。 ~w>h#{RB
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<% K29/7A/
CountBean cb=new CountBean(); C27:tyV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {]^Ixm-,f
CountCache.add(cb); ?mg@z q8
out.print(CountCache.list.size()+"<br>"); "Q.*
CountControl c=new CountControl(); G>V6{g2Q
c.run(); n"EKVw7Y
out.print(CountCache.list.size()+"<br>"); X 0y$xC|<
%>