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: 'B>fRN
LlKvi_z
CountBean.java VC$,Y
~gg(i"V
/* o`,|{K$H
* CountData.java fyaiRn9/
* /%fBkA#n
* Created on 2007年1月1日, 下午4:44 <pyLWmO
*
~$cz`A
* To change this template, choose Tools | Options and locate the template under B >2" O
* the Source Creation and Management node. Right-click the template and choose ]zK'aod
* Open. You can then make changes to the template in the Source Editor. B)>r~v]
*/ cAnL,?_v
Q$u&/g3NvL
package com.tot.count; mCah{~
O|wu;1pQ
/** )IQ5Qu
* bS7rG$n [
* @author S5'ZKk
*/ ^C$Oht,cU
public class CountBean { }81eef4$S
private String countType; wiHGTaR
int countId; 8$9Q=M
/** Creates a new instance of CountData */ M uz+j.0
public CountBean() {} @/jLN
public void setCountType(String countTypes){ nIc:<w]
this.countType=countTypes; X)6}<A
} jT/}5\
public void setCountId(int countIds){ [Ume^
this.countId=countIds; tjLp;%6e
} \A
"_|Yg
public String getCountType(){ " ,k(*
return countType; G4O
$gg
} B6qM0QW
public int getCountId(){ dAg<BK/
return countId; o\<m99Ub
} *WTmS2?'h
} *XN|ZGl/
[=/Yo1:v
CountCache.java 9NzK1V0X
;6+e !h'1
/* =T7lv%u
* CountCache.java Qg9*mlm`
* 3%HF" $Gg
* Created on 2007年1月1日, 下午5:01 ,zXP,(x
* q-?
k=RX`
* To change this template, choose Tools | Options and locate the template under PH!^ww6
* the Source Creation and Management node. Right-click the template and choose (S<Z@y+d
* Open. You can then make changes to the template in the Source Editor. j`H5S
*/ fyHFfPEE
<;eXbO>Q
package com.tot.count; o}^/Km+t
import java.util.*; ={'*C7K)oK
/** (_2Iu%F
* CB!5>k+mC
* @author TTGk"2
Q'
*/ v$n J$M&k
public class CountCache { Gz09#nFZk
public static LinkedList list=new LinkedList(); 7tZvz `\
/** Creates a new instance of CountCache */ Ku'OM6D<
public CountCache() {} Aho zrroV
public static void add(CountBean cb){ mHj3ItXUu
if(cb!=null){ %KjvV<f-a
list.add(cb); Wnf3[fV6P
} 322)r$!"
} 4k7
LM]
} O\~/J/u
<
Uj/m
CountControl.java \+9~\eeXb
7A,QA5G]C
/* B me_#
* CountThread.java Ng Jp2ut
* J`I^F:y*
* Created on 2007年1月1日, 下午4:57 "J.7@\^ h/
* QXaE2}}P
* To change this template, choose Tools | Options and locate the template under 5u:{lcC.X
* the Source Creation and Management node. Right-click the template and choose 'nx";[6(
* Open. You can then make changes to the template in the Source Editor. 'gD,HX
*/ .,vF%pQ
^i;y2c
package com.tot.count; O>vbAIu
import tot.db.DBUtils; dRhsnT+KX
import java.sql.*; sJ3O ]
/** 9y$"[d27;+
* U??T>
* @author RX"~m!26
*/ vG2&qjY1
public class CountControl{ pBR9)T\n
private static long lastExecuteTime=0;//上次更新时间 ~#]$YoQ&O
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?7eD<|
/** Creates a new instance of CountThread */ s{Wj&.)M
public CountControl() {} RJ63"F $
public synchronized void executeUpdate(){ Fv!KLw@
Connection conn=null; @lO(QpdG
PreparedStatement ps=null; `@tnEg
try{ {y\5 9
conn = DBUtils.getConnection(); \9Yc2$dY
conn.setAutoCommit(false); ,Oj
53w=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); x$gVEh*k
for(int i=0;i<CountCache.list.size();i++){ wI{ED
CountBean cb=(CountBean)CountCache.list.getFirst(); j34L*?
CountCache.list.removeFirst(); C)H1<Br7
ps.setInt(1, cb.getCountId()); "TQ3{=j{
ps.executeUpdate();⑴ BIK^<_?+ZU
//ps.addBatch();⑵ k6(9Rw8bCk
} _?m%i]~o
//int [] counts = ps.executeBatch();⑶ uK!G-1
conn.commit(); CHGV1X,
}catch(Exception e){ L2WH-XP=
e.printStackTrace(); %=G*{mK
} finally{ i,R+C.6{
try{ F,)\\$=,
if(ps!=null) { U%qE=u-
ps.clearParameters(); 3B^`xnV
ps.close(); kCVO!@yZz
ps=null; Jmcf9g
} "I
n[= 2w
}catch(SQLException e){} vi8)U]6
DBUtils.closeConnection(conn); HuRq0/"
} wVMR&R<t
} @TqqF:c7
public long getLast(){ ]hC6PKJU
return lastExecuteTime; 1 Vq)& N
} pf%B
public void run(){ *y@Xm~ld
long now = System.currentTimeMillis(); %]iE(!>3oy
if ((now - lastExecuteTime) > executeSep) { m,1Hlp
//System.out.print("lastExecuteTime:"+lastExecuteTime); W6y-~
//System.out.print(" now:"+now+"\n"); 'U|Tye i?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); O&vE 5%x
lastExecuteTime=now; gd=gc<z YP
executeUpdate(); wBaIN]Y,
} D>>?8a
else{ rd\:.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); iQ7S*s+l5O
} na)-'
} G Ch]5\
} -&UP[Mq
//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 []#>r
k~
=TcT` ](o
类写好了,下面是在JSP中如下调用。 y<0RgG1qp
#J_+
SL[
<% L2$`S'U W
CountBean cb=new CountBean(); BnwYyh
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Jp#Onl+d6
CountCache.add(cb); @5tW*:s
out.print(CountCache.list.size()+"<br>"); s/cclFji]
CountControl c=new CountControl(); =IC
cN|
c.run(); R/BW$4/E
out.print(CountCache.list.size()+"<br>"); J.;{`U=:
%>