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: MTn}]blH
Ba76~-gK$
CountBean.java 8o466m6/
=h/61Bl3
/* ceae~
* CountData.java 8TYoa:pZ
* <m%ZDOMa
* Created on 2007年1月1日, 下午4:44 m"
]VQnQ
* zRB LkrC
* To change this template, choose Tools | Options and locate the template under a@!O}f*
* the Source Creation and Management node. Right-click the template and choose a#&\65D
* Open. You can then make changes to the template in the Source Editor. $v=(`=
*/ }s.\B
Cjj(v7[E
package com.tot.count; A%~t[ H
Li\b,_C
/** jOL=vG
* 9jllW[`2F
* @author \\Nt^j3qR
*/ 0RN 7hpf&`
public class CountBean { SU(J
private String countType; xN6}4JB
int countId; fbkAu
/** Creates a new instance of CountData */ Us3zvpy)o
public CountBean() {} .~|[*
q\
public void setCountType(String countTypes){ ;bFd*8?;
this.countType=countTypes; ~l*[=0}
} >P-'C^:V=
public void setCountId(int countIds){ )ZpMB
this.countId=countIds; x)f<lZ^L&H
} '~xiD?:
public String getCountType(){ Sy^@v%P'A
return countType; Or-LQ^~
} a,e;(/#\7
public int getCountId(){ n.1$p
return countId; uIR
} u\)q.`
} ;.7]zn.X]2
J,k.*t:
CountCache.java #,OiZQJC
i"n1E@
/* sfsK[c5bm
* CountCache.java 5Z13s
* r(g2&}o\
* Created on 2007年1月1日, 下午5:01 GQ*or>R1
* bs)Ro/7}
* To change this template, choose Tools | Options and locate the template under ^%qQ)>I=j
* the Source Creation and Management node. Right-click the template and choose O)`ye5>v
* Open. You can then make changes to the template in the Source Editor. \4uj!LgTb
*/ P,k=u$
H h%|}*f_,
package com.tot.count; cpx:4R,
import java.util.*; U \jFB*U
/** 0VIR=Pbp
* vSk1/
* @author S0;s
7X#c
*/ cK'}+
public class CountCache { ;s5JYR
public static LinkedList list=new LinkedList(); I3 YSW
/** Creates a new instance of CountCache */ 3
op{h6
public CountCache() {} th+LScOX
public static void add(CountBean cb){ ~2QD.(
if(cb!=null){ hjp,v)#
list.add(cb); -c%'f&P
} cZAf?,>u
} XKvH^Z4h{l
} x'V:qv*O
y>ePCDR3
CountControl.java .<6'*XR
K pmq C$
/* >eX 9dA3X
* CountThread.java cY.5z:7u~v
* 3GXmyo:o$
* Created on 2007年1月1日, 下午4:57 aF.fd2k
* ^h"@OEga?
* To change this template, choose Tools | Options and locate the template under i \@a&tw
* the Source Creation and Management node. Right-click the template and choose D*ZswHT{y
* Open. You can then make changes to the template in the Source Editor. "1hFx=W+\
*/ 'w_Qs~6~{
P@U2Q%\
package com.tot.count; l$C
Y
gm
import tot.db.DBUtils; *Q;?p
hr
import java.sql.*; FMC]KXSd
/** {G{>Qa|
* |zOwC9-6
* @author ubl)$jZ:Q
*/ _Pn
1n
public class CountControl{ (Z Q?1Qxo
private static long lastExecuteTime=0;//上次更新时间 2W;2._
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 c=p!2jJ1K~
/** Creates a new instance of CountThread */ Kae-Y
public CountControl() {} \
F)}brPc
public synchronized void executeUpdate(){ LmP pt3[
Connection conn=null; <BK?@Xy
PreparedStatement ps=null; p-,Bq!aG$
try{ *Z3b6X'e
conn = DBUtils.getConnection(); /$|-!e<5b\
conn.setAutoCommit(false); o>HGfr,N
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); MZ>Q Rf
for(int i=0;i<CountCache.list.size();i++){ jH37{S-
CountBean cb=(CountBean)CountCache.list.getFirst(); eCG{KCM~_Z
CountCache.list.removeFirst(); mnU8i=v0A
ps.setInt(1, cb.getCountId()); p+${_w>pl{
ps.executeUpdate();⑴ euET)Ccq
//ps.addBatch();⑵ b
T** y?2
} 1?,C d
//int [] counts = ps.executeBatch();⑶ p,7?rI\N
conn.commit(); ~\ v"xV
}catch(Exception e){ WpC9(AX5g
e.printStackTrace(); q<4{&omUJ
} finally{ }bnodb^.7
try{ S(_DR8
if(ps!=null) { EEiWIf&S,
ps.clearParameters(); DDZnNSo<JQ
ps.close(); 1tl qw
ps=null; vZXdc+2l
} dyB@qh~H
}catch(SQLException e){} i$CF*%+t
DBUtils.closeConnection(conn); ;dTxQ_:
} bl#6B.*=
} Uv!VzkPfo
public long getLast(){ rv2;)3/*
return lastExecuteTime; v(P <_}G
} m1M6N`f
public void run(){ 6+:;Mb_S
long now = System.currentTimeMillis(); 593!;2/@
if ((now - lastExecuteTime) > executeSep) { ,Uy;jk
//System.out.print("lastExecuteTime:"+lastExecuteTime); rnBp2'EM
//System.out.print(" now:"+now+"\n"); 8(
bK\-b
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dEam|
lastExecuteTime=now; %I@vM s^
executeUpdate(); P|TM4i]
} nY,LQ0r
else{ |Gr@Mi5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); P[r$KGz
} TNF
} l/A!ofc#)
} p:3w8#)MZ
//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 mv(/M
t
n/YnISt
类写好了,下面是在JSP中如下调用。 ulfs Z:
#p-\Y7f
<% 6sT(t8[
CountBean cb=new CountBean(); Y[W]YPs
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); OXbC\^qo@
CountCache.add(cb); ;Pvnhy
out.print(CountCache.list.size()+"<br>"); 18]Q4s8E
CountControl c=new CountControl(); 8tzL.P^
c.run(); a >k9&
w
out.print(CountCache.list.size()+"<br>"); yGH')TsjD
%>