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: w:%o?pKet1
nc~F_i=
CountBean.java s:OFVlC%\
1/RsptN"v
/* 5A%w 8Qv
* CountData.java b1^vd@(lx
* FemCLvu
* Created on 2007年1月1日, 下午4:44 PpGL/,]X
* ;'?l$
._
* To change this template, choose Tools | Options and locate the template under DQNnNsP:M-
* the Source Creation and Management node. Right-click the template and choose Qt iDTr
* Open. You can then make changes to the template in the Source Editor. <A[E:*`*
*/ ~"!]
3C,L
AuUde$l_
package com.tot.count; Y,GU%[+
?i)f^O
/** l,R/Gl
* XxT#X3D/,"
* @author P<PJ)>
*/ $$D}I*^Dt
public class CountBean { +awW3^1Ed
private String countType;
*-+&[P]m
int countId; R?,an2
/** Creates a new instance of CountData */ ~J5+i9T.)
public CountBean() {} 1q~+E\x
public void setCountType(String countTypes){ iocI:b<
this.countType=countTypes; 03xa'Of>
} O?NeSx1
public void setCountId(int countIds){ >NqYyW,%
this.countId=countIds; Ot:CPm@
} ;KOLNi-B&
public String getCountType(){ RSr
%n1
return countType; !$DIc
} @|Fg,N<Y]
public int getCountId(){ )!Jc3%(B
return countId; f_wvZ&
} a#^B2
} 2Gz}T _e
* 1T&
CountCache.java -|kA)M[
XOxr?NPQ^
/* vbkI^+=,YY
* CountCache.java T:t]"d}}
* 4FEk5D
* Created on 2007年1月1日, 下午5:01 ?f#y1m
* 7q?9Tj3
* To change this template, choose Tools | Options and locate the template under F|F]970
* the Source Creation and Management node. Right-click the template and choose AcS|c:3MUy
* Open. You can then make changes to the template in the Source Editor. O>qll6]{@
*/ 3Dg,GaRk
WzAb|&?
package com.tot.count; x N=i]~
import java.util.*; ]Gpxhg
/** ]P#XVDn+;
* H70LhN
* @author 8j Mk)-
*/ @'YS1 N<
public class CountCache { @L>q(Kg
public static LinkedList list=new LinkedList(); WF2}-NU"
/** Creates a new instance of CountCache */ IKABB W
public CountCache() {} {xwm^p(f
public static void add(CountBean cb){ 2uG0/7
if(cb!=null){ y@ ML/9X8q
list.add(cb); 7]^M>#
} VK}fsOnj0
} t]>Lh>G
} &Q+Ln,(&L
e@c0WlWa
CountControl.java \x)n>{3C
c#a@n 4
/* anIAM
* CountThread.java H:!7:
* >G);j@Q
* Created on 2007年1月1日, 下午4:57 HuB<k3#sPy
* S7=Bd[4
* To change this template, choose Tools | Options and locate the template under pV.Av
* the Source Creation and Management node. Right-click the template and choose Nqw&< x+
* Open. You can then make changes to the template in the Source Editor. >fe-d#!{
*/ dOqOw M.y
Fp@TCPe#
package com.tot.count; y(Y!?X I
import tot.db.DBUtils; {8 8 )~
import java.sql.*; ;} und*q
/** kdCUORMK
* .^N/peUq
* @author @[5xq
*/ Uh7v@YMC
public class CountControl{ =.y~f A!
private static long lastExecuteTime=0;//上次更新时间 D<|qaHB=
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 MG[o%I96
/** Creates a new instance of CountThread */ N e#WI'
public CountControl() {} +lJG(Qd
public synchronized void executeUpdate(){ ${+ @gJ+S
Connection conn=null; cU0s
p
PreparedStatement ps=null; S?RN?1
try{ cj+ FRG~u
conn = DBUtils.getConnection(); j]*j}%hz
conn.setAutoCommit(false); 9&upujVS
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $"0M U
for(int i=0;i<CountCache.list.size();i++){ HOw-]JSP2
CountBean cb=(CountBean)CountCache.list.getFirst(); vLR~'"`F
CountCache.list.removeFirst(); q2. XoCf
ps.setInt(1, cb.getCountId()); ~GTz:nC*
ps.executeUpdate();⑴ u @~JiiC%
//ps.addBatch();⑵ s >e=?W
} Wi[ ~fI8^!
//int [] counts = ps.executeBatch();⑶ ,$;yY)x7U
conn.commit(); ,
FhekaA
}catch(Exception e){ '6Ay&A3N]
e.printStackTrace(); CF+_/s#j^
} finally{ 350_CN,
try{ u`y><w4i
if(ps!=null) { J\d3N7_d
ps.clearParameters(); MxSM@3 v(
ps.close(); At flf2 K
ps=null; S>.SSXlM
} \zieyE
}catch(SQLException e){} (Q%'N3gk
DBUtils.closeConnection(conn); ~\=1'D^6CK
} f` :i.Sr
} /J04^6
public long getLast(){ 1"/He ` 4
return lastExecuteTime; yyv8gH
} m-H-6`]
public void run(){ 9;Itqe{8w
long now = System.currentTimeMillis(); e_s&L,ze
if ((now - lastExecuteTime) > executeSep) { ?47@o1
//System.out.print("lastExecuteTime:"+lastExecuteTime); 0TN;86Mo
//System.out.print(" now:"+now+"\n"); p[<Dk$7K
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); QFg sq{
lastExecuteTime=now; Y]{
>^`G
executeUpdate(); Swp;HW7x
} b8LoIY*
else{ fQL"O}Z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1U^A56CN
} YhOlxON
} S|apw7C
} m>4ahue$
//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 q6_u@:3u
j'%$XvI
类写好了,下面是在JSP中如下调用。 z|asa*
t]$P 1*I
<% Eq$&qV-?(
CountBean cb=new CountBean(); w4W_iaU
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +<xQM h8
CountCache.add(cb); }Z{=|rVE
out.print(CountCache.list.size()+"<br>"); *g y{]
CountControl c=new CountControl(); $ "E).j
c.run(); 8wVY0oRnU
out.print(CountCache.list.size()+"<br>"); uHAT#\m:
%>