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: ;G4g;YHy|
|*JMCI@Mz
CountBean.java =@s {H +
DpvMY94Qh
/* %3es+A@
* CountData.java J?oEzf;M
* zdgSqv
* Created on 2007年1月1日, 下午4:44 I`S?2i2H
* W3y9>]{x^
* To change this template, choose Tools | Options and locate the template under t$(<9
* the Source Creation and Management node. Right-click the template and choose 9PWqoz2c
* Open. You can then make changes to the template in the Source Editor. Dz<vIMLF{
*/ vxl!`$Pi
J9q[u[QZ9O
package com.tot.count; E=RX^ 3+}
PGJkQsp0
/** ?h3t"9
* r(p@{L185
* @author 3u&)6C?YM
*/ 2i~zAD'
public class CountBean { hZUnNQ
private String countType; w~Jy,[@n
int countId; x?n13C
/** Creates a new instance of CountData */ FGu#Pa
public CountBean() {} 3\H0Nkubts
public void setCountType(String countTypes){ oWV^o8& GH
this.countType=countTypes; u$nYddak
} p$}1V2h;
public void setCountId(int countIds){ _7N^<'B
this.countId=countIds; ;]Ko7M(4
} !"s~dL,7
public String getCountType(){ FSA"U9 w<
return countType; D:fLQ8a
} {7d\du&G
public int getCountId(){ QO <.l`F
return countId; }J(o!2.
} CkEbSa<)hK
} |\J! x|xy
7|^5E*8/
CountCache.java DRmN+2I
F.@U
X{J
/* "Is0:au+?}
* CountCache.java k/.a
yLq
* G*W54[
* Created on 2007年1月1日, 下午5:01 o 76QQ+hP
* #({ 9M
* To change this template, choose Tools | Options and locate the template under b";D*\=x
* the Source Creation and Management node. Right-click the template and choose ~v^I*/uY
* Open. You can then make changes to the template in the Source Editor. y4`uU1=
*/ RinaGeim
zjUT:#(k
package com.tot.count; &]P1IQ
import java.util.*; v 8NoD_
/** 7)
* ;/)u/[KAv
* @author )sG/H8
*/ 6}^6+@LG
public class CountCache { |!\5nix3A>
public static LinkedList list=new LinkedList(); y5$AAas
/** Creates a new instance of CountCache */ :Mzkm^7B
public CountCache() {} ^>tqg^
public static void add(CountBean cb){ #S*cFnd
if(cb!=null){ V;%DS)-
list.add(cb); : ?J0e4.]
} O YayTKxN
} hH*/[|z
} 2kV{|`1
U7le> d;L
CountControl.java L6IF0`M<,I
aW@J]slg
/* &#DKB#.2
* CountThread.java IPEJ7n49
* X9/]<Y<!
* Created on 2007年1月1日, 下午4:57 ;1Zz-@
* -:NFF'
* To change this template, choose Tools | Options and locate the template under fd /?x^Z
* the Source Creation and Management node. Right-click the template and choose x9B5@2J1
* Open. You can then make changes to the template in the Source Editor. L"ob))GF
*/ j/*4Wj[
C
Ch38qBp
package com.tot.count; R@Bnrk
import tot.db.DBUtils; mCQn '{)
import java.sql.*; Sz3Tp5b
/** 4M{]YZMw8
* ?VP07
dQTe
* @author [lbe_G;
*/ z*BGaSX %
public class CountControl{ G@I/Dy
private static long lastExecuteTime=0;//上次更新时间 iQj2aK Gs
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :rhh=nHgn
/** Creates a new instance of CountThread */ jo^+
public CountControl() {} %.`<ud
public synchronized void executeUpdate(){ sUTh}.[5
Connection conn=null; |T;NoWO+
PreparedStatement ps=null; fjwUh>[ }
try{ h:l4:{A64
conn = DBUtils.getConnection(); TOvpv@?-
conn.setAutoCommit(false); Z%1{B*(e
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )AoF-&,w
for(int i=0;i<CountCache.list.size();i++){ t$yt8#Tk
CountBean cb=(CountBean)CountCache.list.getFirst(); ?PSVVUq,Z
CountCache.list.removeFirst(); jZLD^@AP
ps.setInt(1, cb.getCountId()); 1Z| {3W
ps.executeUpdate();⑴ g W(7jFl
//ps.addBatch();⑵ nD/;
Gq
} (TQhO$,
//int [] counts = ps.executeBatch();⑶ C#Y_La
conn.commit(); u~VvGLFf5,
}catch(Exception e){ c"x-_Uk
e.printStackTrace(); 8
DE%ot
} finally{ s%p,cz;
,
try{ Q\k|pg?
if(ps!=null) { p:@JC sH=
ps.clearParameters(); #V:28[
ps.close(); QXg9ah~
ps=null; s!Y`1h{
} 6y
d/3k
}catch(SQLException e){} yRGv {G[59
DBUtils.closeConnection(conn); NP?hoqeKs
} @/yJTMcf
} Zwxu3R_
public long getLast(){ q;0QI{:5v
return lastExecuteTime; ;*=MI/"N
} ~w9.}
public void run(){ #HF;yAc
long now = System.currentTimeMillis(); #mK?K
if ((now - lastExecuteTime) > executeSep) { hfQx$cv6
//System.out.print("lastExecuteTime:"+lastExecuteTime); \yNe5
//System.out.print(" now:"+now+"\n"); 4(O;lVT}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); s_`=ugue
lastExecuteTime=now; k5ZkD+0Jo
executeUpdate(); _(.,<R5
} ^KO=8m( )J
else{ =n73bm
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); etk@ j3#
} 0X'2d
} ;\[el<Y)s
} Ja(>!8H>@
//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 U#{^29ik=o
@&
vtY._
类写好了,下面是在JSP中如下调用。 2^.qKY@g@
ZN]LJ4|xu
<% Am&PH(}L
CountBean cb=new CountBean(); ?.%'[n>P
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 4EtP|
CountCache.add(cb); K)!Nf.r$9
out.print(CountCache.list.size()+"<br>"); %e,X7W`'2
CountControl c=new CountControl(); VM [U&g<8n
c.run(); Dd:;8Xo
out.print(CountCache.list.size()+"<br>"); SC6cFyp2
%>