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: qD/GYqvm
}\iH ~T6
CountBean.java Q|gw\.]$&[
iY|zv|;]=
/* {r.KY
* CountData.java BzVF!<!
* 4R c_C0O
* Created on 2007年1月1日, 下午4:44 3?}\Hw
* ;^[VqFpeS
* To change this template, choose Tools | Options and locate the template under UQ7E7yY#
* the Source Creation and Management node. Right-click the template and choose FnZMW, P
* Open. You can then make changes to the template in the Source Editor. =XRTeIZ
*/ &Zzd6[G+
o@6hlLr
package com.tot.count; N7wKaezE
Zb \E!>V
/** vU4Gw4
* wsfN \6e
* @author zL^`r)H
*/ Ky r3)1#J
public class CountBean { O_E\(So
private String countType; 6~oo.6bA
int countId; W[$GB_A)
/** Creates a new instance of CountData */ =DL
|Q
public CountBean() {} :
\{>+!`w
public void setCountType(String countTypes){ =7e|e6
this.countType=countTypes; q7z;b A
} .wdWs tQ
public void setCountId(int countIds){ !nm[ZrSP
this.countId=countIds; I^u$H&
} !,SGKLs.m
public String getCountType(){ Q;V*M
return countType; Fm{/&U^
} 71RG1,
public int getCountId(){ @|=JXSr!KY
return countId; X\=m
} b`9J1p.;
} ,k9@%{4 l
EMTAl;P
CountCache.java u|G&CV#r
vqeWt[W
v
/*
7U3b YU~;
* CountCache.java :rdw0EROy
* rfz\DvVd
* Created on 2007年1月1日, 下午5:01 M*+MhM-
* nEG+TRZ)\
* To change this template, choose Tools | Options and locate the template under 0\y{/P?I$
* the Source Creation and Management node. Right-click the template and choose fQ[&
^S$
* Open. You can then make changes to the template in the Source Editor. UI?AM 34
*/ @)\{u$
1xBg^
package com.tot.count; MF41q%9p
import java.util.*; z#j)uD
/** K3; lst>4
* rUz-\H(-
* @author QE#Ar8tU
*/ G
$F3dx.I
public class CountCache { San=E@3}v!
public static LinkedList list=new LinkedList(); #A:+|{H"
/** Creates a new instance of CountCache */ ]N& Y25oT5
public CountCache() {} #GlQwk3
public static void add(CountBean cb){ e@`"V,i
if(cb!=null){ ZCcKY6b
list.add(cb); =*[98%b
} .{=|N8*py8
} id" -eMwp
} q!qOy/}D
Ir,3' G
CountControl.java -|FSdzvg
v/s6!3pnl
/* i3SrsVSG
* CountThread.java {9,!XiF.:
* D)_67w|u|
* Created on 2007年1月1日, 下午4:57 `\pv^#5HV9
* 9>OPaLn
* To change this template, choose Tools | Options and locate the template under <'N(`.&3C
* the Source Creation and Management node. Right-click the template and choose 4g%BCGsys
* Open. You can then make changes to the template in the Source Editor. kp$w)%2JW
*/ &Q>tV+*
k^%Kw(/
package com.tot.count; ]zt77'J
import tot.db.DBUtils; Ofm?`SE*|
import java.sql.*; IQm[,Fh
/** >QcIrq%=
* Vzmw%f)_+
* @author
7<Yf
*/ =.Hq]l6+
public class CountControl{ Ld9YbL:
private static long lastExecuteTime=0;//上次更新时间 $*k9e ^{S
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !Z}d^$
/** Creates a new instance of CountThread */ CI}zu;4|
public CountControl() {} 4H]~ ]?F&
public synchronized void executeUpdate(){ lG>,&(
Connection conn=null; bzC|aUGM
PreparedStatement ps=null; 'LyEdlC]
try{ tx9;8K3
conn = DBUtils.getConnection(); p_g#iH!*
conn.setAutoCommit(false); 7C::%OF~7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G%q^8#
for(int i=0;i<CountCache.list.size();i++){ [2l2w[7Rid
CountBean cb=(CountBean)CountCache.list.getFirst(); <aPbKDF~V
CountCache.list.removeFirst(); nRSiW*;R
ps.setInt(1, cb.getCountId()); WxrGoo^
ps.executeUpdate();⑴ g2|qGfl{C
//ps.addBatch();⑵ gx55.}
} xl]1{$1M
//int [] counts = ps.executeBatch();⑶ aQTISX;
conn.commit(); dsiQ~ [
}catch(Exception e){ K!cLEG!G
e.printStackTrace(); K8?]&.!
} finally{ b<]Ae!I'
try{ Nj^:8]D)0
if(ps!=null) { m8:9Uv
ps.clearParameters(); *pP&$!bH%
ps.close(); "B34+fOur
ps=null; <pXF$a:s
} iLIv<VK/d
}catch(SQLException e){} cN&]JS,
DBUtils.closeConnection(conn); P2t{il
} bgNN0,+8
} ~rl,Hr3Zo
public long getLast(){ \8}!aTC
return lastExecuteTime; &%\H170S
} tEbR/?,GI
public void run(){ ~TvKMW6/#
long now = System.currentTimeMillis(); MJ..' $>TC
if ((now - lastExecuteTime) > executeSep) { "rJJ~[Y
//System.out.print("lastExecuteTime:"+lastExecuteTime); x&4gy%b
//System.out.print(" now:"+now+"\n"); O'L9 s>B
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); $[*QsU%%
lastExecuteTime=now; hUo}n>Aa
executeUpdate(); >69- [#P!
} 6 *GR_sMm
else{ /9 ^F_2'_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); }NgevsV>;
} %0MvCm
} G oHdhne3
} =mQdM]A)2
//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 )%6h9xyXt
~#SLb=K
类写好了,下面是在JSP中如下调用。 ~5@bWJ
wa f)S=
<% ":meys6t#
CountBean cb=new CountBean(); mFa%d8Y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \kS:u}Ip!
CountCache.add(cb); oz[Mt
i*
out.print(CountCache.list.size()+"<br>"); H-g
CY|W
CountControl c=new CountControl(); +WTO_J7
c.run(); qH9bo-6
out.print(CountCache.list.size()+"<br>"); M. o}?
%>