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: $XI<s$P%(%
ljis3{kn""
CountBean.java "''<:K|
m0*
B[
/* Y5NbY02E
* CountData.java TZP{=v<
* mQvKreo~
* Created on 2007年1月1日, 下午4:44 m@Nx`aS?
* N4v)0
* To change this template, choose Tools | Options and locate the template under 2(rZ@Wl
* the Source Creation and Management node. Right-click the template and choose &B2c]GoW
* Open. You can then make changes to the template in the Source Editor. w2,T.3DT
*/ =%u|8Ea*`
NY;UI(<]
package com.tot.count; q7]WR(e
?% X9XH/!
/** `%XgGHiE
* ^kD?0Fm
* @author ^VIUXa
*/ G9a%N
public class CountBean { M"vcF5q
private String countType; c6uKKh>
int countId; }F`Tp8/&j
/** Creates a new instance of CountData */ 6C0_. =7#
public CountBean() {} oto od
public void setCountType(String countTypes){ 7
b.-&,
this.countType=countTypes; 0C p}
} i]-gO
public void setCountId(int countIds){ F^NR qE
this.countId=countIds; ZYt
__N
} <D dHP
public String getCountType(){ 0V#t ;`Q3
return countType; )[)]@e
} 9HE(*S
public int getCountId(){ G}-.xj]
return countId; 4d 3Znpf
} &v-V_.0(H
} Uaj=}p\+.p
L@4zuzmlb
CountCache.java LA?\~rh!
Z
:9VxZ
/* _tReZ(Vw
* CountCache.java `I>K?
* :ky<`Jfr`
* Created on 2007年1月1日, 下午5:01 9$,gTU_a
* P{Z71a5
* To change this template, choose Tools | Options and locate the template under a!:8`X~[/$
* the Source Creation and Management node. Right-click the template and choose V0 F30rK
* Open. You can then make changes to the template in the Source Editor. zn
?;>Bl
*/ ^!<7#kX
!~N4}!X3du
package com.tot.count; N
&[,nUd
import java.util.*; ]k:m2$le
/** 6}T%m?/ }
* W|#ev*'F
* @author ~8m>DSs)D
*/ 1D[P\r-
public class CountCache { xNm32~
public static LinkedList list=new LinkedList(); _0*>I1F~
/** Creates a new instance of CountCache */ B-~&6D,
public CountCache() {} p},Fwbl
public static void add(CountBean cb){ .G_3blE;
if(cb!=null){ SO<m(o)G2
list.add(cb); 0Ad~!Y+1
} dn\F!
} M91lV(Z
} k<| l\]w
>NRz*h #
CountControl.java ]kkBgjQbS
8KtgSash
/* G\+nWvV7
* CountThread.java L{LU@.;1
* S%X\,N
* Created on 2007年1月1日, 下午4:57 VMIX$#
* 9I\3T6&tr
* To change this template, choose Tools | Options and locate the template under jN%p5nZ^EK
* the Source Creation and Management node. Right-click the template and choose O_Rcd&<mr
* Open. You can then make changes to the template in the Source Editor. U[QD!
*/ F> QT|
8M|)ojH
package com.tot.count; 2ly,l[p8
import tot.db.DBUtils; *fl{Y(_OO
import java.sql.*; 6#)Jl
/** uUz`= 4%A
* d%lHa??/h
* @author =*g$#l4
*/ l}0V+
public class CountControl{ l-S'ATZ0p
private static long lastExecuteTime=0;//上次更新时间 T5azYdzJy
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 QG|GXp_q`
/** Creates a new instance of CountThread */ U>_IYT
public CountControl() {} ],F}}pv
public synchronized void executeUpdate(){ w2d]96*kQe
Connection conn=null; V 7l{hEo3?
PreparedStatement ps=null; }11`98>B6:
try{ %i&/$0.8
conn = DBUtils.getConnection(); >4/L-y+
conn.setAutoCommit(false); XalJo@%-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 9c6GYWIFt&
for(int i=0;i<CountCache.list.size();i++){ h
??C4z
CountBean cb=(CountBean)CountCache.list.getFirst(); A!{.|x[S44
CountCache.list.removeFirst(); 'q92E(
ps.setInt(1, cb.getCountId()); IE)"rTI)b
ps.executeUpdate();⑴ [2'm`tZL
//ps.addBatch();⑵ v1nQs='
} Fi'M"^:r{
//int [] counts = ps.executeBatch();⑶ z]c,}Q
conn.commit(); Q)Iv_N/
}catch(Exception e){ icPp8EwH
e.printStackTrace();
@yt2_
} finally{ RM&H!E<#
try{ Y=a v8Y|`
if(ps!=null) { ;tp]^iB#
ps.clearParameters(); sLG>>d3R1
ps.close(); 'B3Wz a.
ps=null; y~ _za(k
} q#99iiG1
}catch(SQLException e){} JOrELrMx
DBUtils.closeConnection(conn); #Pu@Wx
} ])V2}gH
} G#e9$!
public long getLast(){ DB`$Ru@
return lastExecuteTime; 9q1HSJ1)
} 5wH54gj}
public void run(){ TCHqe19?
long now = System.currentTimeMillis(); x}?DkFuxb
if ((now - lastExecuteTime) > executeSep) { >gk z4.*
//System.out.print("lastExecuteTime:"+lastExecuteTime); dG\U)WA(p
//System.out.print(" now:"+now+"\n"); ]<kupaRQ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); S jVsF1d_
lastExecuteTime=now; X,TTM,1w
executeUpdate(); _[OF"X2
} U{uPt*GUd/
else{ u C,"5C
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]C16y.
~e
} k0|`y U
} ietRr!$.
} sI&i{D
//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 <NG/i i=
x&C%4Y_]
类写好了,下面是在JSP中如下调用。 d4Co^A&
`DLp<_z>
<%
qH#r-
CountBean cb=new CountBean(); zoZ<)x=;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ic*->-!
CountCache.add(cb); 8!4~T,9G
out.print(CountCache.list.size()+"<br>"); ~;M)qR?]W
CountControl c=new CountControl(); gjj 93
c.run(); D|@bGN
out.print(CountCache.list.size()+"<br>"); d/D,P=j"
%>