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: Z*Lv!6WS
mo*ClU7
CountBean.java :k&5Z`>)
_GtG8ebr
/* lm[LDtc
* CountData.java p=jIDM'
* $T2n^yz
* Created on 2007年1月1日, 下午4:44 `21$e
* 2;`F`}BA
* To change this template, choose Tools | Options and locate the template under \L]T|]}(
* the Source Creation and Management node. Right-click the template and choose y%Wbm&h
* Open. You can then make changes to the template in the Source Editor.
gI5Fzk@:
*/ <8sy*A?0z
Su>UXuNdE#
package com.tot.count; O_^X:0}
;=i$0w9 W
/** au?5^u\
* VGL!)1b
* @author l(A>Rw|
*/ @FLa i
public class CountBean { /9k}Ip
private String countType; Q<UKR|6
int countId; O{&wqV5m"
/** Creates a new instance of CountData */ 7a#zr_r
public CountBean() {} 'kE^oX_
public void setCountType(String countTypes){ ~'u %66
this.countType=countTypes; TM*<hC
} /OsTZ"*.2/
public void setCountId(int countIds){
1k39KO@
this.countId=countIds; ]/TqPOi:
} ,]cb3nP
public String getCountType(){ -MTO=#5z
return countType; r4wnfy
} _VFL}<i
public int getCountId(){ \EC7*a0
return countId; (cpaMn@)g
} mEVne.D
} Q"D%xY
R)u ${
CountCache.java >=!$(JgX
@;P\`[(*
/* 3`^NaQ
* CountCache.java ;Y"*Z2U
* f%ynod8
* Created on 2007年1月1日, 下午5:01 5;yVA
* Y:3\z?oV[
* To change this template, choose Tools | Options and locate the template under oP`yBX
* the Source Creation and Management node. Right-click the template and choose \-scGemH
* Open. You can then make changes to the template in the Source Editor. qE)G;Y<,1
*/ @;T?R
1Zi(5S)
package com.tot.count; (Gp|K6
import java.util.*; 6(
~DS9
/** nq3B(
* +f]\>{o4
* @author 7nOn^f D
*/ qcdENIy0b
public class CountCache { ]>'yt #]
public static LinkedList list=new LinkedList(); }rbsarG@
/** Creates a new instance of CountCache */ [R9!Tz
public CountCache() {} BdYl
sYp
public static void add(CountBean cb){ > qDHb'
if(cb!=null){ h6Q-+_5
list.add(cb); eK_Yt~dj
} p}{V%!`_
} :1(UC}v
} 7iM;X2=7}
% m0x]
CountControl.java 69tT'U3vb$
7J$5dFV2
/* o7#Mr`6H
* CountThread.java S&w(H'4N
* ].,TSnb
* Created on 2007年1月1日, 下午4:57 /*2sg>e'QF
* cQ<* (KU
* To change this template, choose Tools | Options and locate the template under Xy'qgK?
* the Source Creation and Management node. Right-click the template and choose \y*,N^w u
* Open. You can then make changes to the template in the Source Editor. ukH?O)0O
*/ *iW$>Yjb
M!E#T-)
package com.tot.count; 76M`{m
import tot.db.DBUtils; i[M]d`<36
import java.sql.*; kFi^P~3D[
/** J&jNONu?
* my(yN|
* @author 9b}AZ]$
*/ xB&6f")
public class CountControl{ .wv!;
private static long lastExecuteTime=0;//上次更新时间 JHCV7$RS
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 lS:R##
/** Creates a new instance of CountThread */ B>TI dQ
public CountControl() {} |}y6U< I
public synchronized void executeUpdate(){ %M_5C4&6
Connection conn=null; B,dHhwO*l
PreparedStatement ps=null; +iL,8eW
try{ S.kFs{;1x
conn = DBUtils.getConnection(); dPfDPb
conn.setAutoCommit(false); _-.~>C
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); raPUx _$PH
for(int i=0;i<CountCache.list.size();i++){ 9&t!U+
CountBean cb=(CountBean)CountCache.list.getFirst(); w}jH,Ew
CountCache.list.removeFirst(); H%\\-Z$#
ps.setInt(1, cb.getCountId()); I$7TnMug
ps.executeUpdate();⑴ 6qgII~F'
//ps.addBatch();⑵ D;l)&"|r?
} LN?b6s75U
//int [] counts = ps.executeBatch();⑶ 0Q_@2
conn.commit(); al3[Ph5G
}catch(Exception e){ nPj/C7j
e.printStackTrace();
LbeMP
} finally{ 0- 'f1 1S
try{ /`Wd+
if(ps!=null) { Hx]{'?
ps.clearParameters(); .+"SDtoX
ps.close(); T'TxC)
ps=null; /rqaUC )A
} -}?ud3f<
}catch(SQLException e){} tt7l%olw
DBUtils.closeConnection(conn); 4gNF;
} .C2.j[>
} \I4*|6kA
public long getLast(){ qt#a_F*rV
return lastExecuteTime; Y=6b oT
} F
;m1I+;
public void run(){ I@f">&^
long now = System.currentTimeMillis(); Cl+TjmOV\`
if ((now - lastExecuteTime) > executeSep) { #VwA?$4g`
//System.out.print("lastExecuteTime:"+lastExecuteTime); $]05?JY#
//System.out.print(" now:"+now+"\n"); X|WAUp?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); y&.[Nt '+
lastExecuteTime=now; 5 ^\f[}
executeUpdate(); QzQTE-SQ
} @zJhJ'~Sl
else{ AjQ^
{P
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); EPz$`#Sh"
} /?; 8F
} _S(]/d(c
} ?q%)8 E
//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
Bkn-
OG
S>]Jc$
类写好了,下面是在JSP中如下调用。 cXJtNW@
3psCV=/z
<% &!3=eVg
CountBean cb=new CountBean(); 3d{v5. C#X
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Y.Er!(pz
CountCache.add(cb); !0g+}
out.print(CountCache.list.size()+"<br>"); QrP$5H{[E
CountControl c=new CountControl(); 042sjt
c.run(); hr<E%J1k%
out.print(CountCache.list.size()+"<br>"); \kpk-[W*x{
%>