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: }G/!9Zq
<aQ<Wy=\
CountBean.java
B\54e Tn
,,G[360
/* 0u) m9eg
* CountData.java /7N&4FrG
* }3O 0nab
* Created on 2007年1月1日, 下午4:44 qdnwaJ;&
* &J?:wC=E
* To change this template, choose Tools | Options and locate the template under /hN;\Z[@
* the Source Creation and Management node. Right-click the template and choose v<3KxP'a
* Open. You can then make changes to the template in the Source Editor. =h\unQ1T
*/ 'MgYSP<
xlcL;e&^P
package com.tot.count; r03%+:
b#nI#!p'
/** ;Zm-B]\
* y{KYR)
* @author Xj9\:M-
*/ ?}e^-//*i
public class CountBean { xp? YM35
private String countType; PrHoN2y5E
int countId; KCIya[$*
/** Creates a new instance of CountData */ $b~[>S-Q
public CountBean() {} 9.%t9RM^
public void setCountType(String countTypes){ eDsB.^|l
this.countType=countTypes; pZcY[a
} QWc,JCu
public void setCountId(int countIds){ u69UUkG
this.countId=countIds; 9=q& SG
} h/Yxm2
public String getCountType(){ JZdRAL2#v
return countType; ]Twyj
} >0z`H|;
public int getCountId(){ [D+,I1u2h
return countId; YkFAu8b>
} x2sKj"2?@
} -2[#1S*
eEBo:Rc9
CountCache.java ~N%+ZXh&E
r+d+gO.
/* g>@a
* CountCache.java bg!(B<!X
* x6)qs-
* Created on 2007年1月1日, 下午5:01 H:|.e)$i
* ^RJ@9`P&t
* To change this template, choose Tools | Options and locate the template under * RyU*au
* the Source Creation and Management node. Right-click the template and choose +_L]d6
* Open. You can then make changes to the template in the Source Editor. UEx13!iFo
*/ P!"{-m'
3%+!qm
package com.tot.count; wfv\xHG
import java.util.*; Wco2i m
/** U)xebU.!S
* Lk!m1J5
* @author m_;fj~m
*/ <(@Z#%O9)
public class CountCache { Y=4
7se=h"
public static LinkedList list=new LinkedList(); kia[d984w
/** Creates a new instance of CountCache */ rFGPS%STS
public CountCache() {} k33\;9@k
public static void add(CountBean cb){ Zf1
uK(6X
if(cb!=null){ SXP(C^?C
list.add(cb); s1E 0atT
} PZQAlO,
} U3C"o|
} &l0K~7)b
Z.&/,UU:4
CountControl.java `<|tC#<z
E}KGZSj
/* 4#}aLP
* CountThread.java er5!ne
* HAL\j5i
* Created on 2007年1月1日, 下午4:57 mI5J]hk
* ;:_AOb31N
* To change this template, choose Tools | Options and locate the template under J;NIa[a
* the Source Creation and Management node. Right-click the template and choose KJV8y"^=Q
* Open. You can then make changes to the template in the Source Editor. tT!'qL.*
*/ bZ1*:k2
7)]boW~Q
package com.tot.count; \I:27:iAL
import tot.db.DBUtils; P
JATRJ1.
import java.sql.*; _7\`xU
/** Y<|JhqOXK
* cE:s\hG
* @author Ufl\
uq3'H
*/ {ZrlbDQX
public class CountControl{ :A
zll s
private static long lastExecuteTime=0;//上次更新时间 aXQS0>G%(
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .CnZMw{'
/** Creates a new instance of CountThread */ ;-8.~Sm
public CountControl() {} dVYY:1PS
public synchronized void executeUpdate(){ WKiP0~
Connection conn=null; QmjE\TcK/
PreparedStatement ps=null; ;&n iZKoe
try{ y%ij)vQY
conn = DBUtils.getConnection(); jhf#
gdz%
conn.setAutoCommit(false); HA8A}d~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \HbZ~I-
for(int i=0;i<CountCache.list.size();i++){ qF4tjza;k
CountBean cb=(CountBean)CountCache.list.getFirst(); nKzm.D gt_
CountCache.list.removeFirst(); %-yzU/`JF
ps.setInt(1, cb.getCountId()); o S= !6h
ps.executeUpdate();⑴ ,+
G
//ps.addBatch();⑵ iAZ8Y/
} LT<2 n.S
//int [] counts = ps.executeBatch();⑶ zwZvKV/g
conn.commit(); =TDKU
}catch(Exception e){ &n;*'M
e.printStackTrace(); u+Ix''Fn#%
} finally{ )-_^vB
try{ wv\K
if(ps!=null) { A!Cby!,
ps.clearParameters(); |dLr #+'az
ps.close(); :-}K:ucaj
ps=null; CdF;0A9.3
} O\.^H/
}catch(SQLException e){} >2znn&gZ
DBUtils.closeConnection(conn); V*b/N
} Cu8mN B{H
} T4]2R
public long getLast(){ F*[E28ia&
return lastExecuteTime; GMJ4v S
} 0TmEa59P
public void run(){ $KbZ4bB[Bo
long now = System.currentTimeMillis(); 4`Ud\Jm[s
if ((now - lastExecuteTime) > executeSep) { ?OFa
Q
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3/`BK{
//System.out.print(" now:"+now+"\n"); (p{%]M
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 8In\Jo$|q>
lastExecuteTime=now; |-x-CSN
executeUpdate(); n"htx|v
} FL'}~il
else{ 9$\s
v5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g8N"-j&@
} ksC_F8Q+
} aO(PVS|P
} 2.aCo, Kb;
//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 QcL@3QC
U0_)J1Yp
类写好了,下面是在JSP中如下调用。 D_d>A+
xRD+!3
<% ;[::&qf
CountBean cb=new CountBean(); G`zNCx.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Mpojabsh
CountCache.add(cb); p
qz~9y~
out.print(CountCache.list.size()+"<br>"); Uw("+[ 5O0
CountControl c=new CountControl(); zbxW
U]<S?
c.run(); _=~u\ $
out.print(CountCache.list.size()+"<br>"); p[C"K0>:_F
%>