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: -@G,Ry-\t
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CountBean.java {);<2]o| 6
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/* QMWDII&t
* CountData.java l]__!X
* LHgEb9\Q
* Created on 2007年1月1日, 下午4:44 ^Y+P(o$HM
* w4\g]\
* To change this template, choose Tools | Options and locate the template under `@Tl7I\
* the Source Creation and Management node. Right-click the template and choose uO}UvMW
* Open. You can then make changes to the template in the Source Editor. _';oT*#
*/ M"<B@p]rk:
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package com.tot.count; 72{Ce7J4
' lMPI@C6r
/** B@v"giJg r
* zDx*R3%
* @author E)utrO R
*/ We*&\e+"T
public class CountBean { MWron_xg
private String countType; KO5! (vi@
int countId; M7g6m
/** Creates a new instance of CountData */ hNF.
public CountBean() {} s'yT}XQ;r
public void setCountType(String countTypes){ ftwn<B
this.countType=countTypes; t*{BN>B
} >7I"_#x1:
public void setCountId(int countIds){ /r@~"Rx '
this.countId=countIds; ;f+bIYQz
} `c%{M4bF\
public String getCountType(){ =E10j.r
return countType; k9vzxZ%s:
} c&a.<e3mL
public int getCountId(){ '\I!RAZ
return countId; :FqHMN
} &R;Cm]jt
} XpU%09K
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CountCache.java RDWUy(iX
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/* 6A,-?W'\
* CountCache.java c#YW>(
* o"-*,:Qe
* Created on 2007年1月1日, 下午5:01 2{fPQQ;#
* a1yGgT a?D
* To change this template, choose Tools | Options and locate the template under _@:O&G2nB
* the Source Creation and Management node. Right-click the template and choose A-om?$7
* Open. You can then make changes to the template in the Source Editor. oQ"J>`',
*/ IMtfi(Y%F
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package com.tot.count; o1?bqVF;6
import java.util.*; )CM3vL {
/** 1]% ]"JbV
* bIP%xl
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* @author %kSpMj|
*/ HyKv5S$
public class CountCache { CZ4Nw]dtR
public static LinkedList list=new LinkedList(); O{w'i|
/** Creates a new instance of CountCache */ {]V+C=`
public CountCache() {} lbUUf}
public static void add(CountBean cb){ h}knn3"S
if(cb!=null){ YR/%0^M'0
list.add(cb); H". [&VP5Z
} CE;J`;
} 5KI lU78
} X8Y)5,`s
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CountControl.java Wd<|DmSy
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/* d:SLyFD$q
* CountThread.java LCouDk(=`
* Y `ySNC
* Created on 2007年1月1日, 下午4:57 s !XJ
* nXFPoR)T
* To change this template, choose Tools | Options and locate the template under 2SV}mK U
* the Source Creation and Management node. Right-click the template and choose ' zz^!@
* Open. You can then make changes to the template in the Source Editor. bji^b@us_
*/ 7x5wT ?2W
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package com.tot.count; n1J;)VyR
import tot.db.DBUtils; dDxb}dx8
import java.sql.*; <2,NWn.
/** N&jHU+{OU
* q\]"}M8
* @author 'Vz Yf^
*/ %]1.)j
public class CountControl{ ![H{ndH!Q
private static long lastExecuteTime=0;//上次更新时间 Wv7hY"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 xixdv{M<FF
/** Creates a new instance of CountThread */ .mwB'Ll
public CountControl() {} XS oHh-
public synchronized void executeUpdate(){ u|{(m_"H
Connection conn=null; |zCT~#
PreparedStatement ps=null; E hw2o-s^
try{ V AnP3:
conn = DBUtils.getConnection(); } 8&?
conn.setAutoCommit(false); KMll8X
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (mOL<h[)IP
for(int i=0;i<CountCache.list.size();i++){ 3$f+3/l
CountBean cb=(CountBean)CountCache.list.getFirst(); 3]wV 1<K
CountCache.list.removeFirst(); Sk7sxy<F'
ps.setInt(1, cb.getCountId()); Or3GrZ!H
ps.executeUpdate();⑴ Ouos f1
//ps.addBatch();⑵ =V>inH
} KJP}0|[
//int [] counts = ps.executeBatch();⑶ M7gb3gw6
conn.commit(); l?<DY$H
0
}catch(Exception e){ X`JoXNqm
e.printStackTrace(); 5`\"UC7?%
} finally{ tTE]j-uT
try{ U~I
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if(ps!=null) { OuMj%I
ps.clearParameters(); A~M .v0
ps.close(); ?d' vIpzO!
ps=null; F_d>@-<
} 1uco{JX<S
}catch(SQLException e){} U%r|hn3
DBUtils.closeConnection(conn); 7KJ%-&L^
} !D|c2
}
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public long getLast(){ z2~\
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return lastExecuteTime; a&Z;$
} gN;
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public void run(){ >UnLq:G
long now = System.currentTimeMillis(); 1YScZ
if ((now - lastExecuteTime) > executeSep) { WX4f3Um
//System.out.print("lastExecuteTime:"+lastExecuteTime); YkF52_^_
//System.out.print(" now:"+now+"\n"); aJLc&o 8Yg
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); * -X`^R
lastExecuteTime=now; Aaug0X
executeUpdate(); zK>}x=
} p735i`8
else{ uNf97*~_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); K1CgM1 v
} q+ 2v9K@
} ^Eif~v
} W4q
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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 _sAcvKH
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类写好了,下面是在JSP中如下调用。 #H;1)G(/
VQ;'SY:`
<% _0o65?F
CountBean cb=new CountBean(); dlH&8
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *nB-]
w/
CountCache.add(cb); t1ers> h
out.print(CountCache.list.size()+"<br>"); :Z.P0=
CountControl c=new CountControl(); HdRwDW@7=
c.run(); } 8[
out.print(CountCache.list.size()+"<br>"); &2r[4
%>