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: Si}HX!s
ri~<~oB2:
CountBean.java (3vHY`9
&7?R+ZGo
/* DsD zkwJE
* CountData.java y k161\
* 0CvsvUN@
* Created on 2007年1月1日, 下午4:44 z T%U!jqI
* yTM{|D]$(
* To change this template, choose Tools | Options and locate the template under L7Dh(y=;7
* the Source Creation and Management node. Right-click the template and choose ?^HfNp9
* Open. You can then make changes to the template in the Source Editor. OIb
*/ )8gGv
Aez2*g3
package com.tot.count; 8Ad606
%6j)=IOts
/** d?idTcgs
* m"tOe?
* @author @!=\R^#p
*/ {kI#A?M
public class CountBean { f}%D"gz
private String countType; )+I.|5g
int countId; ZBD;a;wx
/** Creates a new instance of CountData */ vP!GJX&n5
public CountBean() {} iSK+GQ~
public void setCountType(String countTypes){ ]pA(K?Lbg
this.countType=countTypes; :
DG)g3#
} *2"6fX[
public void setCountId(int countIds){ rk2xKm^w
this.countId=countIds; $ls[|N:y0l
} C@y8.#l
public String getCountType(){ M
s9E@E
return countType; qgt[ ~i*
} x90*yaw>h
public int getCountId(){ :)f7A7 :;
return countId; pfuW
} ,n,RFa
} -php6$|
Eq%@"-mo
CountCache.java D,l,`jv*
$L4/I !Yf
/* 5vzceQE}
* CountCache.java wHjLd$ +o
* FwKj+f"
* Created on 2007年1月1日, 下午5:01 vZ7gS
* eS/B24;*
* To change this template, choose Tools | Options and locate the template under tU wRE|_
* the Source Creation and Management node. Right-click the template and choose 9V uq,dv
* Open. You can then make changes to the template in the Source Editor. pC,o2~%{
*/ 2U
kK0ls
rf+:=|/_3
package com.tot.count; RNVbcd
import java.util.*; &>WWzikB*
/** "e3["'
* pVp:@0h
* @author `i~ Y Fr
*/ .@ C{3$,VG
public class CountCache { UUo;`rkT
public static LinkedList list=new LinkedList(); Ko>&)%))$X
/** Creates a new instance of CountCache */ f67NWFX
public CountCache() {} 4o:hyh
public static void add(CountBean cb){ R$kpiqK
if(cb!=null){ '&O/g<Z}q
list.add(cb); ^(}585b
} @*N)i?>
} w
JwX[\
} xZ5M/YSyG
wle@vCmr
CountControl.java 3q[WHwmm
W|k0R4K]]
/* ajl
2I/D
* CountThread.java wu<])&F
* Bc-yxjsw
* Created on 2007年1月1日, 下午4:57 SZ![%)83
* ({0)@+V8
* To change this template, choose Tools | Options and locate the template under OIHz I2{
* the Source Creation and Management node. Right-click the template and choose ?{"mP 'dD
* Open. You can then make changes to the template in the Source Editor. :yT-9Ze%q
*/ /76 1o\Q
D-imL;|
package com.tot.count; +!-~yf#RE
import tot.db.DBUtils; iyZZ}M
import java.sql.*; ylf[/='0K
/** kyh_9K1
* u
D 5%E7
* @author ulHn#)
*/ 8 S`9dSc
public class CountControl{ 3Rg}+[b
private static long lastExecuteTime=0;//上次更新时间 8?t"C_>*e
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 /NT[ETMk+
/** Creates a new instance of CountThread */ XALI<ZY
public CountControl() {} *MNHT`Y^o
public synchronized void executeUpdate(){ d<w~jP\
Connection conn=null; F-(dRSDNM
PreparedStatement ps=null; ln*icaDqf
try{ $h9='0Wi0'
conn = DBUtils.getConnection(); ?zJpD8e
conn.setAutoCommit(false); /5AW?2)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); #0I{.Wy]
for(int i=0;i<CountCache.list.size();i++){ e)nimq
{6
CountBean cb=(CountBean)CountCache.list.getFirst(); G |*(8r()
CountCache.list.removeFirst(); :Br5a34q
ps.setInt(1, cb.getCountId()); P=L$;xgp
ps.executeUpdate();⑴ |6:=}dE#[
//ps.addBatch();⑵ /z7VNkD
} m4k
Bj*6c{
//int [] counts = ps.executeBatch();⑶ >M%\T}5
conn.commit(); ^da44Qqu
}catch(Exception e){ &Wp8u#4L
e.printStackTrace(); X C86-b)E
} finally{ z@s5m}
try{ 5\mTr)\R
if(ps!=null) { 1:C:?ZC#c
ps.clearParameters(); n6WY&1ZE~
ps.close(); wCMQPt)VS
ps=null; +`mGK:>
} _eSdnHWx
}catch(SQLException e){} LVIAF0kX
DBUtils.closeConnection(conn); U8#xgz@
} &ej8mq"\
} 4:3rc7_
1
public long getLast(){ Z.L?1V8Q1
return lastExecuteTime; foF19_2 ,
} >t,M
public void run(){ %1
KbS
[
long now = System.currentTimeMillis(); c97{Pu
if ((now - lastExecuteTime) > executeSep) { 9Ywpej*+
//System.out.print("lastExecuteTime:"+lastExecuteTime); K`}{0@ilCw
//System.out.print(" now:"+now+"\n"); Mvj;ic6iK
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); H?1xjY9sl
lastExecuteTime=now; lA!"z~03*
executeUpdate(); 4 PLk
} oq/G`{`\
else{ gC%G;-gm
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Agh`]XQ2
} p Y)5bSA
} M`,~ mU
} U=Y)V%
//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 1[F3 Z
sRVIH A,
类写好了,下面是在JSP中如下调用。 C-eA8pYY/
-Ue$T{;RoH
<% \mM<\-'p
CountBean cb=new CountBean(); |rw%FM{F
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); N(6|yZ<J3M
CountCache.add(cb); mM.*b@d-
out.print(CountCache.list.size()+"<br>");
>DM44
CountControl c=new CountControl(); V~DMtB7
c.run(); :nHKl
out.print(CountCache.list.size()+"<br>"); /StTb,
%>