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: Q(ec>+oi
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CountBean.java yu@u0vlc
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/* %Y<3v\`_
* CountData.java "BD$-]
* lehuJgz'OO
* Created on 2007年1月1日, 下午4:44 $BWA=2$
* 5!}fd/}Uk
* To change this template, choose Tools | Options and locate the template under ,S\AUUt%
* the Source Creation and Management node. Right-click the template and choose : tcqb2p
* Open. You can then make changes to the template in the Source Editor. _cD-E.E%
*/ #i}:CI>2
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package com.tot.count; e[*%tx H
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/** `ls^fnJTpf
* y`p(}X`>
* @author &U0Y#11Cx
*/ >J_%'%%f
public class CountBean { Gjo&~*;
private String countType; 'v'=t<wgl
int countId; ,NoWAmv
/** Creates a new instance of CountData */ <;':'sW
public CountBean() {} NM&R\GI
public void setCountType(String countTypes){ &xMQ
this.countType=countTypes; \s">trXwX
} W#lt_2!j
public void setCountId(int countIds){ Wc!.{2
this.countId=countIds; rEG!A87Zz
} EawtT
public String getCountType(){ :}p<Hq 8Z
return countType; 8I,/ysT:
} X UcM~U-
public int getCountId(){ j`ybz G^
return countId; tboc7Hor4
} 6HR^q
} 1i:Q
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CountCache.java TC^fyxq
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/* mM)d`br
* CountCache.java YKG}4{T
* [pYjH+<
* Created on 2007年1月1日, 下午5:01 R\,qL-Br
* 6T ,'Oz
* To change this template, choose Tools | Options and locate the template under w>uo-88
* the Source Creation and Management node. Right-click the template and choose ZRLS3*`
* Open. You can then make changes to the template in the Source Editor. '?dT<w=Y&
*/ u[?M{E/HU
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package com.tot.count; i+eDBg6
import java.util.*; 1h#UM6
/** MgUjB~)Y
* $7'KcG
* @author G>w+J'7
*/ p| o?nI
public class CountCache { L#9g ~>~
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ `CF.-Vl3J#
public CountCache() {} ;;lOu~-*$p
public static void add(CountBean cb){ 'NDDj0Y
if(cb!=null){ ?-D'xqc
list.add(cb); +W[NgUrGJ
} {;E]#=|
} U.p"JSH
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} "=vH,_"Ql
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CountControl.java NB?y/v
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/* ]gG&X3jaKq
* CountThread.java (H-}z`sy/@
* :zLeS-
* Created on 2007年1月1日, 下午4:57 W:* {7qJ
* 66%4p%#b4
* To change this template, choose Tools | Options and locate the template under \1mTKw)S
* the Source Creation and Management node. Right-click the template and choose HA0Rv#p
* Open. You can then make changes to the template in the Source Editor. *zTEK:+_
*/ SWPb=[WEz
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package com.tot.count; G+zIh}9
import tot.db.DBUtils; FCA]zR1
import java.sql.*; 2}jC%jR2
/** }Z3+z@L
* *#g[
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* @author Z@ZSn0
*/ \:|"qk
public class CountControl{ @w{"6xc%a
private static long lastExecuteTime=0;//上次更新时间 o0\d`0-el
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 2V)qnMxAZJ
/** Creates a new instance of CountThread */ j2%?-(U
public CountControl() {} i*2l4
public synchronized void executeUpdate(){ (4oO8aBB
Connection conn=null; #xBh62yIuP
PreparedStatement ps=null; D|R aj\R
try{ QDpzIjJj
conn = DBUtils.getConnection(); q"|#KT^)
conn.setAutoCommit(false); YCnKX<Wv
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); bo04y)Iz
for(int i=0;i<CountCache.list.size();i++){ XYdr~/[HPy
CountBean cb=(CountBean)CountCache.list.getFirst(); 9 Z79
CountCache.list.removeFirst(); h&j9'
ps.setInt(1, cb.getCountId()); )R@M~d-o
ps.executeUpdate();⑴ a0=>@?
//ps.addBatch();⑵ :]+p#l
} _ !H8j/b
//int [] counts = ps.executeBatch();⑶ SJXP}JB_
conn.commit(); Mv#\+|p 1x
}catch(Exception e){ :1,xs e
e.printStackTrace(); wS}Rl}#Oh?
} finally{ TU}./b@F
try{ 8PtX@s43\
if(ps!=null) { BFH=cs
ps.clearParameters(); ]#t5e>o|
ps.close(); p4M7BK:nf
ps=null; `;H3['~$
} L qdzqq
}catch(SQLException e){} Sxg&73;ZV
DBUtils.closeConnection(conn); %y_AT2A
} 4oywP^I
} #xTu {
public long getLast(){ q;#:nf"
return lastExecuteTime; Z&Ao;=Gp1
} A!.* eIV|
public void run(){ xA {1XS}
long now = System.currentTimeMillis(); (X( c.Jj
if ((now - lastExecuteTime) > executeSep) { <Z^qBM
//System.out.print("lastExecuteTime:"+lastExecuteTime); ztHEXM.
//System.out.print(" now:"+now+"\n"); ~zD*=h2C
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); :Yy8Ie#
lastExecuteTime=now; (043G[H'.
executeUpdate(); F,>-+~L=
} Dh~Z8!*
else{ tj;<EaM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ' &j]~m
} 5_~QS
} rtY4B~_
} ]/y69ou
//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 :MbD=sX
#uHl
类写好了,下面是在JSP中如下调用。 |cd=7[B
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<% os~}5QJ
CountBean cb=new CountBean(); %x zgTZ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); kF o&!
CountCache.add(cb); 7<p?E7
out.print(CountCache.list.size()+"<br>"); 8bP4
CountControl c=new CountControl(); >
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c.run(); 9a;8^?Ld%S
out.print(CountCache.list.size()+"<br>"); OJ2I (8P
%>