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: &W6^sj*k5U
\=0Vi6!Mc
CountBean.java x{WD;$J
"wh ,Ue
/* fPW@{~t
* CountData.java "OnGE$
* K0Fh%Y4)QH
* Created on 2007年1月1日, 下午4:44 s.NGA.]$
* WaR`Kp+>
* To change this template, choose Tools | Options and locate the template under #$qTFN
* the Source Creation and Management node. Right-click the template and choose \6*I'|5d
* Open. You can then make changes to the template in the Source Editor. hTi$.y!k
*/ Ck7uJI<x
pBA7,z"`mP
package com.tot.count; ~Vjl7G\7i
q.`NtsW!\+
/** 5(HG|
* x{/g(r={}
* @author `$aZ0+
*/ )U{Qj5W+F
public class CountBean {
_~ iw[*#u
private String countType; SQt4v"
int countId; -5QZJF2~
/** Creates a new instance of CountData */ A
'];`
public CountBean() {} )~ h}
public void setCountType(String countTypes){ o`N9!M
this.countType=countTypes; :1KpGj*F
} (,Df^4%7
public void setCountId(int countIds){ <
F+l
this.countId=countIds; C/6V9;U
} :'*~uJrR
public String getCountType(){ D]Xsvv
#
return countType; 55c|O
} w%BL
public int getCountId(){ M} v/tRI
return countId; |64~K\X
} +pn
N!:q
} }s<4{:cv+
><HE;cVg?
CountCache.java l}sjD[2
K1!j fp
/* n3
r3"~i
* CountCache.java j
Dv{/)
* G?/DrnK:
* Created on 2007年1月1日, 下午5:01 u.Tcg^ v
* v^iL5y!
* To change this template, choose Tools | Options and locate the template under ]G< Vg5
* the Source Creation and Management node. Right-click the template and choose a ]tVd#
* Open. You can then make changes to the template in the Source Editor. Px`!A EFd[
*/ ':m,)G5&
ly3\e_z:G
package com.tot.count; HYSIN^<oy
import java.util.*; tr}Loq\y
/** mZ"4&U
* `t'W2X
* @author {
W{]L:
*/ o.\F.C$
public class CountCache { N `F~n%N
public static LinkedList list=new LinkedList(); LsS
/** Creates a new instance of CountCache */ k4y'b
public CountCache() {} dP]\Jo=Yh
public static void add(CountBean cb){ G..aiA
if(cb!=null){ r/6o \-
list.add(cb); tQYM&6g
} +@k+2?]
FO
} RcU}}V
} ' x35=@
uurh??R
CountControl.java !6>~?gNd
s
3f-7f<
/* O]Qd<%V'x
* CountThread.java 3Xy-r=N. l
* en*GM}<V
* Created on 2007年1月1日, 下午4:57 /F'sb[
* 4s{~r
* To change this template, choose Tools | Options and locate the template under (uZ&V7l
* the Source Creation and Management node. Right-click the template and choose '|p$)yx2
* Open. You can then make changes to the template in the Source Editor. HqD^B[jS
*/ Pax|x15
^)*-Bo)I
package com.tot.count;
^J)mH[
import tot.db.DBUtils; b:]V`uF?
import java.sql.*; T\j{Bi5 \J
/** 8jo p_PG'
* 0rG^,(3m
* @author `gf0l /d
*/ D}8[bWF
public class CountControl{ ?FF4zI~
private static long lastExecuteTime=0;//上次更新时间 kw%};;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 O%KsD[W;
/** Creates a new instance of CountThread */ (~wqa 3
public CountControl() {} X1-'COQS%&
public synchronized void executeUpdate(){ qPy1;maXP
Connection conn=null; kN4{13Qs*
PreparedStatement ps=null; o{q{!7DH@
try{ .ndCfdy~
conn = DBUtils.getConnection(); ?3zc=J"t
conn.setAutoCommit(false); aYS!xh206
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2:7zG"$
for(int i=0;i<CountCache.list.size();i++){ n+q!l&&
CountBean cb=(CountBean)CountCache.list.getFirst(); Zxs|%bQ
CountCache.list.removeFirst(); PV\+P6aIb
ps.setInt(1, cb.getCountId()); ^^as'Dk
ps.executeUpdate();⑴ oO|KEY(
//ps.addBatch();⑵ 0C
irfcs}Z
} 6vNrBB
//int [] counts = ps.executeBatch();⑶ bITPQ7+
conn.commit(); KZ
;k)O.Ov
}catch(Exception e){ yiC^aY=-
e.printStackTrace(); +&( Mgbna
} finally{ qr4pR-Gdr
try{ ^!ZC?h!rG
if(ps!=null) { YS@ypzc/
ps.clearParameters(); >TnTnF WX
ps.close(); Be=u&T:~
ps=null; 3|4|*6
} VE{3} S
}catch(SQLException e){} EGzzHIZ`!
DBUtils.closeConnection(conn); (b~T]3Es
} 6qoyiT%P&
} [] `&vWZ
public long getLast(){ _'>oXQJ
return lastExecuteTime; h
WtVWVNL
} 2ZMb<b4H
public void run(){ e .2ib?8
long now = System.currentTimeMillis(); 6dN7_v)
if ((now - lastExecuteTime) > executeSep) { T| V:$D'
//System.out.print("lastExecuteTime:"+lastExecuteTime); IsM}'.
//System.out.print(" now:"+now+"\n"); A1D^a,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9m<jcxla$
lastExecuteTime=now; }v*G_}^
executeUpdate(); 4@n1Uk
} `c5"d
else{ :'3XAntZA
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X=!^] 3zH
} G{ sOR
} vss(twg
} : $Y9jR
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 m)v"3ib
Nj
xoTLI
类写好了,下面是在JSP中如下调用。 bE#,=OI$
)ufg9"\
<% luuX2Mx>o
CountBean cb=new CountBean(); %g$V\zmU
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /VS[pXXT|
CountCache.add(cb); ,dov<U[ia
out.print(CountCache.list.size()+"<br>"); (-xS?8x$
CountControl c=new CountControl(); NI#:|}CYS
c.run(); , 5kKimTt
out.print(CountCache.list.size()+"<br>"); G!W[8UG
%>