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: fkjo
&!=[.1H<
CountBean.java m0(]%Kdw
}wkZ\q[
/* @$bEY#*C
* CountData.java ,^#{k!uaC{
* 74u_YA<"
* Created on 2007年1月1日, 下午4:44 t R(Nko
* @9X+ BdQU
* To change this template, choose Tools | Options and locate the template under 'U8% !
* the Source Creation and Management node. Right-click the template and choose O 6}eV^y
* Open. You can then make changes to the template in the Source Editor. 2&+Nr+P
*/ ^o@N.+`&<
u#&ZD|
package com.tot.count; HAtf/E]
JPq2C\Ka
/** FO/[7ZH
* / ~\ I
* @author m+7/ebj{A
*/ >#[u"CB
public class CountBean { 2U
Q&n` A
private String countType; i;GF/pi
int countId; %Uz
5Ve
/** Creates a new instance of CountData */ c'gV
public CountBean() {} TODTR7yGo
public void setCountType(String countTypes){ m+ww
this.countType=countTypes; nR2pqaKc
} lz-t+LD@ST
public void setCountId(int countIds){ &0='z
this.countId=countIds; 'Rg6JW\
} 3tZC&!x?
public String getCountType(){ K~I%"r|l
return countType; (*CGZDg
} w.2[Xx~
public int getCountId(){ %JsCw8C6?
return countId; MS~|F^g
} %9qG|A,cA
} F6$QEiDu@
J_H=GHMp}
CountCache.java e~+VN4D&b>
oieZopYA
/* Up/s)8$.
* CountCache.java E7K(I ?
* U fzA/
* Created on 2007年1月1日, 下午5:01 M&/([>Q
* W_sAk~uK/
* To change this template, choose Tools | Options and locate the template under "B~ow{3
* the Source Creation and Management node. Right-click the template and choose 6*({ZE
* Open. You can then make changes to the template in the Source Editor. CI~P3"`]
*/ ktu{I
L,<5l?u
package com.tot.count; a0]n>C`~
import java.util.*; a1 I"Sh
/** wACx}'+M
* av.L%l&d
* @author c@]_V
*/ sr*3uI-)L
public class CountCache { m/`"~@}&
public static LinkedList list=new LinkedList(); Y9K$6lz
/** Creates a new instance of CountCache */ -S7y1 ) 7
public CountCache() {} NdlJdq
public static void add(CountBean cb){ 9P M\D@A{
if(cb!=null){ :*`5|'G}
list.add(cb); }z$_=v
} [It
E+{U
} 1syI%I1
} :k"VR,riF
j%V95M%$
CountControl.java Gh:hfHiG
r@XH=[:
/* _eE hIQ9
* CountThread.java {);S6F$[3
* %~`y82r6
* Created on 2007年1月1日, 下午4:57 8)1k>=
* (1|_Nr
* To change this template, choose Tools | Options and locate the template under xD#r5
* the Source Creation and Management node. Right-click the template and choose ;ZSJ-r
* Open. You can then make changes to the template in the Source Editor. 9MmAoLm
*/ *&m{)cTs
'|9fDzW"]
package com.tot.count; 7E-1
#4
import tot.db.DBUtils; S\F;b{S1
import java.sql.*; )G
a%Eg9
/** _Kw<4$0<p
* B}(+\Q$I
* @author [YsN c
*/ 2[ #7YWs
public class CountControl{ (eOzntp8
private static long lastExecuteTime=0;//上次更新时间 ,Qd;t
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4Hk eXS.
/** Creates a new instance of CountThread */ <yxEGjm
public CountControl() {} =xa:>Vh#
public synchronized void executeUpdate(){ qNH=
W?T8.
Connection conn=null; 9qHbV
9,M
PreparedStatement ps=null; [KT'aGK$
try{ sI7<rI.t){
conn = DBUtils.getConnection(); K)z!e;r
conn.setAutoCommit(false); R`_RcHY:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); h^tU*"
for(int i=0;i<CountCache.list.size();i++){ O!3MXmaO
CountBean cb=(CountBean)CountCache.list.getFirst(); bm &$wf
CountCache.list.removeFirst(); vp4l g1/
ps.setInt(1, cb.getCountId()); [xTu29X.
ps.executeUpdate();⑴ mihR
*8p
//ps.addBatch();⑵ |#6B<'e'
} p\7(`0?8VN
//int [] counts = ps.executeBatch();⑶ *G<K@k
conn.commit(); S:*.,zC
}catch(Exception e){ AWY#t&
e.printStackTrace(); 6zJ<27
} finally{ y" (-O%Pe
try{ >AbgJ*X.
if(ps!=null) { ^RS?y8
ps.clearParameters(); x/UmpJD+
ps.close(); F@76V$U.
ps=null; B``)
} &Ow[
}catch(SQLException e){} .??[qBOTE
DBUtils.closeConnection(conn); KKPQ[3g
} Y6>@zznk
} #LGAvFA*_F
public long getLast(){ fO;#;p.
return lastExecuteTime; 7kQZ$sLc
} fG+/p 0sJ?
public void run(){ |Sne\N>%
long now = System.currentTimeMillis(); -*Voui
if ((now - lastExecuteTime) > executeSep) { SnK#YQCDt
//System.out.print("lastExecuteTime:"+lastExecuteTime); P|>pm]>C
//System.out.print(" now:"+now+"\n"); aCq ) hR
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); |6M:JI8
lastExecuteTime=now; u@;6r"8q
executeUpdate(); LQ7.RK
} yBd#*3K1
else{ U]aH4N
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); K>"]*#aBv
} ?"d25LyN
} WSt&?+Y
} x*Lm{c5+
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 u~WE}VC
^1#"FU2cP
类写好了,下面是在JSP中如下调用。 Qh4<HQ<9
O%1X[
<% 6
J&_H(^
CountBean cb=new CountBean(); ^""Ss
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); r+4<Lon~
CountCache.add(cb); N^ )\+*tf1
out.print(CountCache.list.size()+"<br>"); d)_fI*:f
CountControl c=new CountControl(); m0: IFE($
c.run(); QoGvjf3z
out.print(CountCache.list.size()+"<br>"); W[+=_B
%>