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: ,L9ioYbp
Bq#B+JwX
CountBean.java Vh5Z'4N
2f7]=snCG
/* E3,Nc`'m9
* CountData.java f|-%.,
* uUI@!)@2
* Created on 2007年1月1日, 下午4:44 E|hW{ oX3
* ""u>5f
* To change this template, choose Tools | Options and locate the template under gC\^"m
* the Source Creation and Management node. Right-click the template and choose h(3ko
An
* Open. You can then make changes to the template in the Source Editor. D;WQNlTU
*/ Q
a8;MxK`
Dro2R_j{
package com.tot.count; |GnqfD
{{ /-v3n
/** \} +b_J6-
* zkmfu~_)
* @author I 7s}{pG
*/ t{Xf3.
public class CountBean { /;a b"b
private String countType; /U =eB?>
int countId; C9%2}E3Z$)
/** Creates a new instance of CountData */ },(Ln%M
public CountBean() {} ~xV|<;
public void setCountType(String countTypes){ Ym/y2B(
this.countType=countTypes; 0X[uXf
} sj\kp
ni
public void setCountId(int countIds){ )-_To&S*
this.countId=countIds; -|nHwSrCZ/
} Iji9N!Yx
public String getCountType(){ =P\Tk)(`
return countType; kMY1Xb
} UfAN)SE"
public int getCountId(){ Mg76v<mv<
return countId; ?wYvBFRn7"
} eIY![..J/N
} h!h<!xaclW
.0f6b
CountCache.java v'H\KR-;
55]E<2't
/* PcK;L(
* CountCache.java a.!|A(zw
* %$H~
* Created on 2007年1月1日, 下午5:01 ~AbTbQ3
* O[/l';i
* To change this template, choose Tools | Options and locate the template under BARs1^pR4
* the Source Creation and Management node. Right-click the template and choose leomm+f^
* Open. You can then make changes to the template in the Source Editor. y(uE
*/ ej&ZE
n
Ec;{N
package com.tot.count; ZVX!=3VT
import java.util.*; &$+nuUA
/** dE0p>4F
* WyDL ah^/
* @author Dhy@!EOS
*/ vgvJ6$#
public class CountCache { rLzN#Zoi
public static LinkedList list=new LinkedList(); 8KhE`C9z
/** Creates a new instance of CountCache */ `oUuAL
public CountCache() {} 1pT-PO3=
public static void add(CountBean cb){ iF1E 5{dH
if(cb!=null){ ppu WcGo
list.add(cb); |'" 17c&
} @ATJ|5.gr
} )`B
n"=
} uy^vQ/
"ZU CYYre
CountControl.java _yJAn\
ui$JQ _P
/* ?YTngIa
* CountThread.java ap[{`u
* j9G1
_
* Created on 2007年1月1日, 下午4:57 GN%|'eU
* 38Bh9>c3
* To change this template, choose Tools | Options and locate the template under DsZBhjCB
* the Source Creation and Management node. Right-click the template and choose a= *qsgPGL
* Open. You can then make changes to the template in the Source Editor. e;ej/)no`
*/ ,]UCq?YW)T
GIGC,zP@k
package com.tot.count; ,
e6}p
import tot.db.DBUtils; //_aIp
import java.sql.*; Q7vTTn\
/** cXY;Tw45
* cun&'JOH?U
* @author 7@*l2edXm+
*/ /degBL+
public class CountControl{ UZ` <D/
private static long lastExecuteTime=0;//上次更新时间 +^\TG>le
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .3JLa8y
/** Creates a new instance of CountThread */ t'pY~a9F
public CountControl() {} ]&mN~$+C
public synchronized void executeUpdate(){ Fw!TTH6l0
Connection conn=null; 6*]g~)7`Q~
PreparedStatement ps=null; /PuN+M
try{ SlRQi:
conn = DBUtils.getConnection(); !QTfQ69Y0
conn.setAutoCommit(false); ;@R=CQ6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2GRdfX
for(int i=0;i<CountCache.list.size();i++){ ]s))O6^f
CountBean cb=(CountBean)CountCache.list.getFirst();
l,n
V*Z
CountCache.list.removeFirst(); bXw!fYm&
ps.setInt(1, cb.getCountId()); fi.[a8w:W
ps.executeUpdate();⑴ QSxR@hC
//ps.addBatch();⑵ /\0rRT
} WK<:(vu.
//int [] counts = ps.executeBatch();⑶ 2[8C?7_K0?
conn.commit(); }KZt7)
}catch(Exception e){ Gec?
e.printStackTrace(); ^[]@dk9
} finally{ 9h$08l
try{ jLZ^EM-
if(ps!=null) { c{X:0man
ps.clearParameters(); lPywrTG0
ps.close(); " A}S92
ps=null; X5hamkM*m
}
nGqD{!i<
}catch(SQLException e){} O^+H:Y|
DBUtils.closeConnection(conn); yD-L:)@"
} 7ZsBYP8%
} k,mgiGrQ
public long getLast(){ c\\'x\J7
return lastExecuteTime; BS_ 3|
} f0lpwwe
public void run(){ |pA
long now = System.currentTimeMillis(); g$N/pg2>cT
if ((now - lastExecuteTime) > executeSep) { [10y 13
//System.out.print("lastExecuteTime:"+lastExecuteTime); 6|Qg=4_FHt
//System.out.print(" now:"+now+"\n"); sG6ts,={
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); t(RJc
lastExecuteTime=now; \69h>h
executeUpdate(); {Hu@|Q\~&
} <V~B8C!)
else{ oY K(=j
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~Gz
b^
} 8NJxtT~0c~
} &I|\AG"X}
} 'wg>=|Q5
//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 "^UJC-
FZ0wtS2
类写好了,下面是在JSP中如下调用。 +p
Y*BP+~i
|*T3TsP u
<% ~g|Z6-?4Jj
CountBean cb=new CountBean(); RiPxz=kr
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !)1gGXRY
CountCache.add(cb); M:9
6QM~
out.print(CountCache.list.size()+"<br>"); {%"n[DLps
CountControl c=new CountControl(); $q
iY)RE
c.run(); pr) `7VuKp
out.print(CountCache.list.size()+"<br>"); !G8=S'~~
%>