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: "%rU1/@#
WE
/1h
CountBean.java ~sWXd~\
mGw*6kOIS
/* 2,h]Y=.s
* CountData.java fLkC|
* ob[G3rfd@Z
* Created on 2007年1月1日, 下午4:44 %wJ?+D/
* /(}YjeS
* To change this template, choose Tools | Options and locate the template under (~PT(B?
* the Source Creation and Management node. Right-click the template and choose 7Mh!@Rd_V
* Open. You can then make changes to the template in the Source Editor. pWoeF=+y]W
*/ +' .o
2aUE<@RU[
package com.tot.count; R?2T0^0
>RKepV(X7
/** NucLf6
* pNc4o@-
* @author E# *`u
*/ +<f!#4T
public class CountBean { .,gVquqMY
private String countType; ".
wG~H
int countId; (t"rzH
/** Creates a new instance of CountData */ WmZ,c_
public CountBean() {} qim|=
public void setCountType(String countTypes){
fG|+!
this.countType=countTypes; Xb7G!Hk#g
} I7jIA>ZZi
public void setCountId(int countIds){ IYB;X
this.countId=countIds; p&3~n:
Fo
} c/`Rv{*'o
public String getCountType(){ $kn"S>jV
return countType; KPdlg.
} $
Bdxu
public int getCountId(){ Owm2/
return countId; *saO~.-;4
} "Kt[jV;6
} p&,2@(Q
YM]ZL,8
CountCache.java SZ"^>}zl=
vxx7aPjC
/* Y4n;[nHQ(
* CountCache.java NI%
()
* oi}\;TG
* Created on 2007年1月1日, 下午5:01 IDr$Vu4LCW
* LjA>H>8%[
* To change this template, choose Tools | Options and locate the template under \ .jT"Z~
* the Source Creation and Management node. Right-click the template and choose Og3bV_,"
* Open. You can then make changes to the template in the Source Editor. h`$2/%?
*/ BFyVq
@ 6{U*vs
package com.tot.count; S)d_A
import java.util.*; 9b*1-1"
/** _"#ucM=B:-
* Uw5`zl
* @author )0NE_AZ?
*/ gAgP("
public class CountCache { 7A[`%.!F6
public static LinkedList list=new LinkedList(); {,rVA(I@
/** Creates a new instance of CountCache */ /R44x\nhr
public CountCache() {} ;l6tZ]-"
public static void add(CountBean cb){ 1p9+c~4l:
if(cb!=null){ |);-{=.OdQ
list.add(cb); b bO1`b-
} B?tO&$s
} (j;6}@
} E64d6z^7u
*T'>-nm]
CountControl.java H|iY<7@
.\>I-
/* c0%%X!!$
* CountThread.java p4OiCAW;
* pZ4]oK\*
* Created on 2007年1月1日, 下午4:57 q"[8u ]j
* `?ijKZ}y5
* To change this template, choose Tools | Options and locate the template under 8?rRLM4
* the Source Creation and Management node. Right-click the template and choose Mo2b"A;}|
* Open. You can then make changes to the template in the Source Editor. H]7;OM/g
*/ *.DTcV
p}'uCT
ga
package com.tot.count; P]G`Y>#$r
import tot.db.DBUtils;
B)M& FO
import java.sql.*; Vuqm{bo^
/** eY1$smh t
* ]7, mo
* @author $3Ct@}=n
*/ i>C:C>~
public class CountControl{ zU'\r~c
private static long lastExecuteTime=0;//上次更新时间 3S'juHTe
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 THM\-abz
/** Creates a new instance of CountThread */ Ppzd.=E
public CountControl() {} kgvB80$4
public synchronized void executeUpdate(){ +)Pv6Zog[
Connection conn=null; *|RQ
)
PreparedStatement ps=null; {zc<:^r^
try{ *kXSl73 k
conn = DBUtils.getConnection(); heliL/
conn.setAutoCommit(false); GP5Y5)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); KGclo-,
for(int i=0;i<CountCache.list.size();i++){ @]#0jiS
CountBean cb=(CountBean)CountCache.list.getFirst(); ^ )Lh5
CountCache.list.removeFirst(); e%'$Vx0kA
ps.setInt(1, cb.getCountId()); 3 G?^/nB
ps.executeUpdate();⑴ 6.Nu[-?
//ps.addBatch();⑵ T7AFL=
} s9<fPv0w
//int [] counts = ps.executeBatch();⑶
7)IBIlV
conn.commit(); $Wy7z^t
}catch(Exception e){ n7"e 79
e.printStackTrace(); q9RCXo>Y+1
} finally{ +b.qzgH>r
try{ Ey77]\
if(ps!=null) { )K8k3]y&
ps.clearParameters(); Oph4&Ip[w
ps.close(); Hut
au^l
ps=null; 2B8p3A
} 66?!"w
}catch(SQLException e){} _XtLO-D
DBUtils.closeConnection(conn); ?=]`X=g6
} kSH3)CC P
} <_02)6j
public long getLast(){ 2sjP":
return lastExecuteTime; /LM*nN$%
} *J!oV0#1
public void run(){ <R7*00
long now = System.currentTimeMillis(); 5#.uA_Fov
if ((now - lastExecuteTime) > executeSep) { H(ht{.sjI
//System.out.print("lastExecuteTime:"+lastExecuteTime); w~EXO;L2
//System.out.print(" now:"+now+"\n"); JbG\Ywi0]
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); oh`I$
lastExecuteTime=now; )^uLZMNaI
executeUpdate(); F_!6C-z
} .9Bimhc6K
else{ Y;je ::"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); o$m64l
} Eo\#*Cv*
} J"8bRp=/|
} !Y-MUZ$f
//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 sJX/YGHt
h)q:nlKUW
类写好了,下面是在JSP中如下调用。 *eL%[B
j-ugsV`2=*
<% L1`^~m|
CountBean cb=new CountBean(); _> .TB\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $nQ; ++
CountCache.add(cb); M}}9
out.print(CountCache.list.size()+"<br>"); {o7ibw=E)
CountControl c=new CountControl(); R! ?8F4G
c.run(); "uCx.Q9ef
out.print(CountCache.list.size()+"<br>"); f3U#|(%(*
%>