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: (#Y~z',I
$)i`!7`4=
CountBean.java -+#%]P8l
;H_/o+
/* X 'Ss#s>g
* CountData.java ^X=Q{nB
* iNO>'7s7
* Created on 2007年1月1日, 下午4:44 &`"DG$N(
* ALF0d|>=uj
* To change this template, choose Tools | Options and locate the template under /WrB>w
* the Source Creation and Management node. Right-click the template and choose f98,2I(>`+
* Open. You can then make changes to the template in the Source Editor. |3*9+4]a
*/ jjs/6sSRk
sVLvnX,
package com.tot.count; 9BCW2@Kp
=kjKK
/** >rSjP1-F
* bjZJP\6
* @author 067c/c
*/ _Cmmx`ln
public class CountBean { "[ bkdL<
private String countType; L$ZjMJ
int countId; d>NGCe
/** Creates a new instance of CountData */ 7FB?t<x
public CountBean() {} B VBn.ut
public void setCountType(String countTypes){ ]P4WfV
d
this.countType=countTypes; R=D]:u<P
} Njq}M/{U
public void setCountId(int countIds){ o-,."|6
this.countId=countIds; YB#fAU
} =$>=EBH,cm
public String getCountType(){ `+7F H
return countType; 615Ya<3f8
} ,6)N.
public int getCountId(){ ks405
return countId; wj)LOA0
} vB:\ZX4
} IpP%WW u
wwUI ;g
CountCache.java *}?[tR5
j6
wFks
/* x.Sf B[SZ
* CountCache.java i'>6Qo
* zp:dArh0
* Created on 2007年1月1日, 下午5:01 =Tj{)=^/#
* &,X}M
* To change this template, choose Tools | Options and locate the template under mG~_*8}e<
* the Source Creation and Management node. Right-click the template and choose ("$/sT
* Open. You can then make changes to the template in the Source Editor. `MtzA^X r
*/ 8fC4j`!
OgQdyU
package com.tot.count; ]?9*Vr:P^
import java.util.*; nL@'??I1
/** mypV[
* BI'>\hX/V
* @author cc@W
6W
*/ LC%ococ
public class CountCache { -IPo/?}
public static LinkedList list=new LinkedList(); <r%K i`u(p
/** Creates a new instance of CountCache */ +;N]34>S7
public CountCache() {} Q@D7\<t
public static void add(CountBean cb){ VtBC~?2U)B
if(cb!=null){ &D,Iwq
list.add(cb); d?,'$$ aB
} v 6 ~9)\!j
} 222 Y?3>@D
} :4ryi&Y
}:Z.g
CountControl.java M'*s5:i
*ap,r&]#F
/* (q)}`1d'
* CountThread.java 7]=&Q4e4
* #'L<7t
K
* Created on 2007年1月1日, 下午4:57 i8iT}^
* x|H`%Z
* To change this template, choose Tools | Options and locate the template under bA;OphO(
* the Source Creation and Management node. Right-click the template and choose a:FU- ^B4~
* Open. You can then make changes to the template in the Source Editor. O-?rFNavxp
*/ bI):-2&s}
qmS9*me
{
package com.tot.count; mF4W4~"
import tot.db.DBUtils; 5ggyk0
import java.sql.*; |v&)O)Jg
/** Xs03..S
* Tz
@<hE
* @author %hB-$nE
*/ l.Q
public class CountControl{ 3efOgP=L
private static long lastExecuteTime=0;//上次更新时间 Cxf K(F
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~7m`p3W@
/** Creates a new instance of CountThread */ ?<?Ogq"<
public CountControl() {} XlppA3JON|
public synchronized void executeUpdate(){ g~lv/.CnA+
Connection conn=null; "?"
:
PreparedStatement ps=null; -&+:7t
try{ Cbbdq%ySI
conn = DBUtils.getConnection(); ~i,d%a
conn.setAutoCommit(false); &l(T},-X
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 7)?C+=,0
for(int i=0;i<CountCache.list.size();i++){ H2X_WSwm
CountBean cb=(CountBean)CountCache.list.getFirst(); @0 +\:F
CountCache.list.removeFirst(); P1#g{f
ps.setInt(1, cb.getCountId()); LdUz;sb
ps.executeUpdate();⑴ G% F#I
//ps.addBatch();⑵ B=SA
+{o
} corm'AJ/
//int [] counts = ps.executeBatch();⑶ |J$A%27
conn.commit(); xUJ(tG3
}catch(Exception e){ (zhZ}C,VF
e.printStackTrace(); vNO&0~
} finally{ B'Yx/c&n
try{ 0s n$QmW:
if(ps!=null) { L]Tj]u)
ps.clearParameters(); >6es
5}
ps.close(); @iz Onc:
ps=null; ,NO[Piok
} 7nt(Rtbsu
}catch(SQLException e){} I|X`9
DBUtils.closeConnection(conn); `bP`.Wm
} <ZC.9
} Kz'GAm\
public long getLast(){ oj 8r*
return lastExecuteTime; X5WA-s(?0
} [P2>KQ\
public void run(){ SKG
U)Rn;
long now = System.currentTimeMillis(); pY&6p~\p
if ((now - lastExecuteTime) > executeSep) { snbXAx1L
//System.out.print("lastExecuteTime:"+lastExecuteTime); SSe;&Jk2d
//System.out.print(" now:"+now+"\n"); +y|
B"}x
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +17!v_4^
lastExecuteTime=now; .Xlo-gHk
executeUpdate(); |nMjv]#
} 01(U)F\
else{ [* xdILj
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); uQ=u@qtp
} Ar-Vu{`
} FPc`J
} <IrhR,@M,L
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Q%CrB>|@
Q Xd`P4a
类写好了,下面是在JSP中如下调用。 (Mc{nFqS
!t% 1G.
<% P|NGAd
CountBean cb=new CountBean(); 5BrN
uR$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ju2H0AQ
CountCache.add(cb); ZayJllaq^
out.print(CountCache.list.size()+"<br>"); |Iy;_8c
CountControl c=new CountControl(); {$S"Sj
c.run(); r^k+D<k[7
out.print(CountCache.list.size()+"<br>"); =Jp:dM*
%>