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: <F&53N&Zc
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CountBean.java rZkl0Y;n\
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/* +WfO2V.
* CountData.java Tq,xW
* 8i Xt8XY3
* Created on 2007年1月1日, 下午4:44 up
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* /;V:<mekf
* To change this template, choose Tools | Options and locate the template under 5K[MKfT
* the Source Creation and Management node. Right-click the template and choose :#nv:~2]
* Open. You can then make changes to the template in the Source Editor. ?D9>N'yH8
*/ k35E,?T
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package com.tot.count; yd~}CF
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/** }e8u p*#me
* %?i~`0-:n%
* @author oQ/ Dg+Xp
*/ bPHtP\)
public class CountBean { qN@0k>11?
private String countType; &p83X
int countId; %Z!3[.%F
/** Creates a new instance of CountData */ !6pE0(V^+4
public CountBean() {} CoTe$C7
public void setCountType(String countTypes){ L)-1( e<x
this.countType=countTypes; NsUP0B}.
} 1<$z-y'
public void setCountId(int countIds){ 1#
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this.countId=countIds; dvPlKLp
} P`]p&:
public String getCountType(){ a~Nh6 x
return countType; YAJr@v+Ls
} M#o'h c
public int getCountId(){ _n=,H
return countId; ,!Q^"aOT:
} l#^weXSlk
} ?CO..l
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CountCache.java &p_V<\(%
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/* }&Kl)2:O
* CountCache.java TM<;Nj[*n
* y_}jf,b4
* Created on 2007年1月1日, 下午5:01 iiD}2yb
* Pt[ b;}
* To change this template, choose Tools | Options and locate the template under N)Qz:o0W
* the Source Creation and Management node. Right-click the template and choose p$_X\,F
* Open. You can then make changes to the template in the Source Editor. CA5q(ID_
*/ Z[G:
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package com.tot.count; 3w$Ib}7
import java.util.*; E-"b":@:
/** hYY-Eq4TC
* 1YJ@9 *l
* @author k\A[p\
*/ B0$.oavC
public class CountCache { m(p0)X),_i
public static LinkedList list=new LinkedList(); ,;~@t:!c
/** Creates a new instance of CountCache */ qY$]^gS
public CountCache() {} d6+{^v$#
public static void add(CountBean cb){ [$FiXH J
if(cb!=null){ A`ScAzx5{
list.add(cb); p$1y8Zbor
} #xfPobQ>il
} {mmQv~|5q
} t:yJ~En]=
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CountControl.java %hV]vm
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/* 5%;=(Oig
* CountThread.java ^Kfm(E
* @@} ]qT*
* Created on 2007年1月1日, 下午4:57 J[jzkzSu`
* }CB9H$FkCY
* To change this template, choose Tools | Options and locate the template under zsmlXyP'e!
* the Source Creation and Management node. Right-click the template and choose EJaGz\\
* Open. You can then make changes to the template in the Source Editor. -@?4Tfl
*/ |rwx;+
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package com.tot.count; 4StoEgFS
import tot.db.DBUtils; N`rz>6,k1
import java.sql.*; qz&?zzz;
/** WI\jm&H r
* TpAso[r
* @author uE-|]QQo
*/ %WAaoR&u
public class CountControl{ dj5@9X
private static long lastExecuteTime=0;//上次更新时间 N%fDgK
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 'A)9h7k}
/** Creates a new instance of CountThread */ !]2`dp\!
public CountControl() {} +!eh\.u|]
public synchronized void executeUpdate(){ GyLp&aa
Connection conn=null; y?ypRCgO.u
PreparedStatement ps=null; :[!b";pR
try{ NXSjN~aG2
conn = DBUtils.getConnection(); `=19iAp.
conn.setAutoCommit(false); 'l6SL-
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?eOw8Rom
for(int i=0;i<CountCache.list.size();i++){ Y20T$5{#
CountBean cb=(CountBean)CountCache.list.getFirst(); Q1[EiM3
CountCache.list.removeFirst(); t 4>\;
ps.setInt(1, cb.getCountId()); UIK4]cYC'
ps.executeUpdate();⑴ 't'2z
//ps.addBatch();⑵ cn2SMa[@S
} Q+; N(\
//int [] counts = ps.executeBatch();⑶ <Xb$YB-c
conn.commit();
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}catch(Exception e){ DQhs tXX
e.printStackTrace(); !MEA@^$#
} finally{ V* H7m'za
try{ CMC9%uq
if(ps!=null) { tqzr+
ps.clearParameters(); h1Logm+m
ps.close(); PXo^SHJ+gt
ps=null; rH9[x8e
} !]l;n
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}catch(SQLException e){} D),hSqJ"
DBUtils.closeConnection(conn); n |Q'>
} b{a\j%
} !n|4w$t"V
public long getLast(){ "J>8ZUP
return lastExecuteTime; 36\_Y?zx%
} PYr'1D'
public void run(){ DTz)qHd#X
long now = System.currentTimeMillis(); wPxtQv
if ((now - lastExecuteTime) > executeSep) { F&$~]R=&
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1-}M5]Y
//System.out.print(" now:"+now+"\n"); g]jCR*]
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); uQiW{Kja2
lastExecuteTime=now; AQTV1f_
executeUpdate(); wG
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} 2 sK\.yS
else{ mO&zE;/[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} HleMzykF
} }TRVCF1
} cXbQ
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 KEo?Cy?%ff
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类写好了,下面是在JSP中如下调用。 Lrq e:\
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<% q+W*?a)
CountBean cb=new CountBean(); 7uq^TO>9f
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); jf=\\*64r4
CountCache.add(cb); S3ZIC\2
out.print(CountCache.list.size()+"<br>"); Ir6g"kwCKq
CountControl c=new CountControl(); ZiC~8p_f
c.run(); LTcZdQd$
out.print(CountCache.list.size()+"<br>"); \-CL}Z}S
%>