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:
C B}BQd
BnEdv8\,&s
CountBean.java {7#03 k
x*8O*!ZZ
/* h
W.2p+
* CountData.java C|e+0aW
* $-G`&oT
* Created on 2007年1月1日, 下午4:44 Lar r}o=
* Lx+`<<_dJ
* To change this template, choose Tools | Options and locate the template under 12gw#J/)9h
* the Source Creation and Management node. Right-click the template and choose W,N L*($^
* Open. You can then make changes to the template in the Source Editor. E/O5e(h
*/ q.oLmX
@FX{M..
package com.tot.count; ;L6Xs_L~
L$JI43HZ
/** .9 kyrlm
* oX|?:MS:
* @author QrS$P09=\
*/ __)qw#
public class CountBean { };SV!'9s?~
private String countType; YOw?'+8
int countId; sd!sus|( R
/** Creates a new instance of CountData */ "3y} F
public CountBean() {} zl)&U=4l
public void setCountType(String countTypes){ YN#XmX%
this.countType=countTypes; :WX0,-Gn
} WN0c%kz=
public void setCountId(int countIds){ ;QPy:x3
this.countId=countIds; f-+.;`H)T
} )Qr6/c8}
public String getCountType(){ h3 @s2 fK
return countType; p {C9`wi)
} _t.FL@3e
public int getCountId(){ fOBN=y6x
return countId; %cj58zO|y
} |\{Nfm=:%
} R+Lk~X^*l'
>l2w::l%
CountCache.java >UN vkQ:
_;G=G5r
/* iwo$\
* CountCache.java <IH*\q:7
* 22vq=RO7Z
* Created on 2007年1月1日, 下午5:01 a|.20w5
* Wm>b3:
* To change this template, choose Tools | Options and locate the template under Q7k.+2
* the Source Creation and Management node. Right-click the template and choose QNJ\!+,HV
* Open. You can then make changes to the template in the Source Editor. #JS`e_3Rr
*/
SsRVd^=;x
*<dHqK`?C
package com.tot.count; u+DX$#-n!]
import java.util.*; ysth{[<5F3
/** 5&(3A|P2
* \3j)>u,r
* @author hho%~^bn(
*/ jZ#UUnR%
public class CountCache { #Q+R%p[D
public static LinkedList list=new LinkedList(); H5p5S\g-)
/** Creates a new instance of CountCache */ )[
b#g(Y(
public CountCache() {} 7vNtv9
public static void add(CountBean cb){ ~,Mr0
if(cb!=null){ xppkLoPK
list.add(cb); %yhI;M^
} >;}]pI0T
} |D(&w+(
} *[
#*n n
^Y<M~K972
CountControl.java Q
3X
cuMc*i$w!
/* &CO|Y(+
* CountThread.java <i7agEdZD
* ` U#Po_hq
* Created on 2007年1月1日, 下午4:57 TK %<a/
* %^U"Spv;
* To change this template, choose Tools | Options and locate the template under "uS7PplyO
* the Source Creation and Management node. Right-click the template and choose I4ctxMVP
* Open. You can then make changes to the template in the Source Editor. 3.~h6r5-
*/ *#GDi'0
?&\h;11T
package com.tot.count; U%,;N\:_
import tot.db.DBUtils; #'iPDRYy
import java.sql.*; L6 kZ2-6
/** @ AggznA8
* 4L11P
* @author '2xcce#
*/ wzbz}P>
public class CountControl{ i :EO(`
private static long lastExecuteTime=0;//上次更新时间 /Mx.:.A&$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 kU(kU2u%9
/** Creates a new instance of CountThread */ %xpd(&)n
public CountControl() {} Yg|"-
public synchronized void executeUpdate(){ BDp:9yau
Connection conn=null; AtT"RG-6
PreparedStatement ps=null; 9nO(xJ"e4
try{ 7y>(H<^>
conn = DBUtils.getConnection(); pMDH
conn.setAutoCommit(false); $>(9~Yh0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G V=OKf#
for(int i=0;i<CountCache.list.size();i++){ *bU% @O
CountBean cb=(CountBean)CountCache.list.getFirst(); ik1XGFy?
CountCache.list.removeFirst(); ?4MSgu
ps.setInt(1, cb.getCountId()); HoV{U zm
ps.executeUpdate();⑴ ysl8LK
//ps.addBatch();⑵ i.F8
} o[n<M>@
//int [] counts = ps.executeBatch();⑶ qr9Imr0w<
conn.commit(); ^+URv
}catch(Exception e){ b.@H1L
e.printStackTrace(); Pm;I3r=R\
} finally{ u(8~4P0w
try{ F6DxvyANr
if(ps!=null) { YV4
:8At1
ps.clearParameters(); MN\i-vAL8
ps.close(); EZ*t$3.T
ps=null; Dl&PL
} xg{VP7
}catch(SQLException e){} f~U#z7
DBUtils.closeConnection(conn); K:uQ#W.&
} f%L:<4
} C)U #T)
public long getLast(){ A3<^ U
return lastExecuteTime; XnPJC'
} e"lD`*U8R
public void run(){ yr%yy+(.k
long now = System.currentTimeMillis(); 2c"/QT
if ((now - lastExecuteTime) > executeSep) { T<XfZZ)l<`
//System.out.print("lastExecuteTime:"+lastExecuteTime); 8F\~Wz 7K
//System.out.print(" now:"+now+"\n"); m'3OGvd
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [#7D~Lx/
lastExecuteTime=now; F68},N>vr@
executeUpdate(); ruzMag)
} "-28[a3q
else{ T\)dt?Tv#\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 5"$e=y/
} ~37R0`C
} 48H5_9>:
} loR,XW7z
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 )CFk`57U
+jv}\Jt
类写好了,下面是在JSP中如下调用。 G2=F8kL
D8gQRQ
<% ?U}sQ;c$
CountBean cb=new CountBean(); 9)jo7,VM
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @>+^W&
CountCache.add(cb); .zQ4/
out.print(CountCache.list.size()+"<br>"); ;A
x=]Q
CountControl c=new CountControl(); )\RzE[Cb
c.run(); =.VepX|?D
out.print(CountCache.list.size()+"<br>"); 7Y%!,ff
%>