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: /\ fR6|tJ
\&d1bq
CountBean.java qi@Nz=t#HJ
ZW))Mx#K=T
/* E7$ aT^
* CountData.java LI-ewea
* tG]W!\C'h
* Created on 2007年1月1日, 下午4:44 k Jz^\Re
* ,M]W_\N~E
* To change this template, choose Tools | Options and locate the template under ~p+
`pwjY1
* the Source Creation and Management node. Right-click the template and choose \V~B+e
* Open. You can then make changes to the template in the Source Editor. v#d3W|
~
*/ +v%+E{F$+
.5HD i-
package com.tot.count; 9|jMN
j]vo
l/?bXNt
/** UChLWf|'
* *r4FOA%P
* @author hAgrs[OFj
*/ Z{u]qI{l
public class CountBean { `m V(:
private String countType; rxxVLW
int countId; Eb,M+c?
/** Creates a new instance of CountData */ #x;d+Q@
public CountBean() {} ?RE"<L
public void setCountType(String countTypes){ )3F}IgD
this.countType=countTypes; = m|<~t
} 2n"-~'3\
public void setCountId(int countIds){ dM"5obEb
this.countId=countIds; BD$Lf,_
} J^WX^".E
public String getCountType(){ a{e1g93}
return countType; ZkibfVwe
} 1< b~="
public int getCountId(){ >xRUw5jN
return countId; "SuG6!k3
} #m{F*(%
} 2(Xu?W 7d
!FK)iQy$0
CountCache.java (Rs;+S
&/Gf@[
/* iqF|IVPoi
* CountCache.java Ut%{pc 7^F
* %f\j)qw
* Created on 2007年1月1日, 下午5:01 $5#DU__F/
* OZKZv,
* To change this template, choose Tools | Options and locate the template under C,O9?t
* the Source Creation and Management node. Right-click the template and choose 1Uah IePf
* Open. You can then make changes to the template in the Source Editor. 6XAofN/5f
*/ !;t6\Z8&
X&Ospl@H
package com.tot.count; <UIE-#
import java.util.*; >y!R}`&0^t
/** 'K23oQwDB
* k/Urz*O
* @author FrRUAoFO
*/ N5MWMN[6aP
public class CountCache { 29z@ !
public static LinkedList list=new LinkedList(); XB[EJGaX
/** Creates a new instance of CountCache */ B$q5/ L$}
public CountCache() {} 1n)YCSA
public static void add(CountBean cb){ Tv,ZS
if(cb!=null){ Lm^vS u
list.add(cb); c?Zi/7
} sVlQ5M oo(
} u3cl7~- yW
} t ,EMyZ
: t
D`e<
CountControl.java wgQx.8 h>
L8pKVr
/* z@<jZM
* CountThread.java 6ZXRb
* K,bX<~e5
* Created on 2007年1月1日, 下午4:57 M^n^wz
*
PmE8O
* To change this template, choose Tools | Options and locate the template under LCSJIt
* the Source Creation and Management node. Right-click the template and choose O^~nf%
* Open. You can then make changes to the template in the Source Editor. a0k/R<4
*/ q:wz!~(>
(AG((eV
package com.tot.count; &jrc]
import tot.db.DBUtils; 7a4Z~r27/
import java.sql.*; 5sB~.z@
/** b.
:2x4
* >+%0|6VSb
* @author H@|m^1
*/ B;<zA' 1
public class CountControl{ a 4?c~bs
private static long lastExecuteTime=0;//上次更新时间 UD&pL'{s
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]~pM;6Pu0
/** Creates a new instance of CountThread */ 5IRUG)Icr
public CountControl() {} DnCIfda2g
public synchronized void executeUpdate(){ ;|,*zD
Connection conn=null; !W b Q9o
PreparedStatement ps=null; 6anH#=(
try{ OP``+z>
conn = DBUtils.getConnection(); WuQ;Da0+_F
conn.setAutoCommit(false); |QyZ:`0u
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); h.xtkD)Y~
for(int i=0;i<CountCache.list.size();i++){ cf\GC2+"^$
CountBean cb=(CountBean)CountCache.list.getFirst(); -^>7\]
CountCache.list.removeFirst(); _!yUr5&,Br
ps.setInt(1, cb.getCountId()); U_wIx
ps.executeUpdate();⑴ rwpH9\GE
//ps.addBatch();⑵ :?gp}.
} t&o&gb
//int [] counts = ps.executeBatch();⑶ aC3Qmo6?m
conn.commit(); P(p|NRD@1
}catch(Exception e){ Nm#[ A4
e.printStackTrace(); Tog'3k9Uw
} finally{ ka$la;e3
try{ m-9ChF:U
if(ps!=null) { m>DJ w7<
ps.clearParameters(); SS&G<3Ke
ps.close(); @f#6Nu
ps=null; k4JTc2b
} c`UizZ
}catch(SQLException e){} =_$Hn>vO
DBUtils.closeConnection(conn); 4@jX{{^6%
} Upc_"mkI.
} q3u:Tpn4%
public long getLast(){ k P=~L=cK
return lastExecuteTime; 5QG?*Z~?7
} i&L!?6 5-f
public void run(){ =pb ru=/
long now = System.currentTimeMillis(); Nfd'|#
if ((now - lastExecuteTime) > executeSep) { nYTPcT4x|
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3g3Znb
//System.out.print(" now:"+now+"\n"); Ee{Y1W
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); rDLgQ{Sea
lastExecuteTime=now; @,q <CF@Y
executeUpdate();
: !wt/Y
} l(Uwci
else{ rrs0|=
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); pvdCiYo1r
} 50Ov>(f@7
} C|S~>4`
} `>HrO}x^
//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 kq>I?wg
L1MG("R
类写好了,下面是在JSP中如下调用。 3#{Al[jq
5>fAO =u!Q
<% tf>"fU\P
CountBean cb=new CountBean(); 55zy]|F"
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ? RID4xu!
CountCache.add(cb); Ime"}*9
out.print(CountCache.list.size()+"<br>"); PebyH"M(
CountControl c=new CountControl(); n}8}:3"
c.run(); |0VZ1{=*
out.print(CountCache.list.size()+"<br>"); {Lsl2@22
%>