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: dI^IK
<&5m N
CountBean.java S9G+#[.|
]cm6 |`pz
/* 46bl>yk9<
* CountData.java q^a|wTC
* UvxSMD:A
* Created on 2007年1月1日, 下午4:44
76-jMcGi
* 9Uha2o
* To change this template, choose Tools | Options and locate the template under .xGo\aD
* the Source Creation and Management node. Right-click the template and choose ;} l T
* Open. You can then make changes to the template in the Source Editor. bauA}3
*/ L[?nST18%
S!;LF4VA
package com.tot.count; {O^TurbTFA
%K[daXw6E8
/** _1^8xFe2
* 5@P%iBA4(3
* @author d2rL 8jW
*/ &]P"48NT
public class CountBean { qib7Z]j
private String countType; QsiJ%O Q
int countId; 6M ^IwE
/** Creates a new instance of CountData */ (1 CJw:
public CountBean() {} egm)a
public void setCountType(String countTypes){ 55.;+B5L*
this.countType=countTypes; L#D9@V'z
} 5Go0}'*%
public void setCountId(int countIds){ y
'Ol Q2U
this.countId=countIds; ddsUz1%l
} A\K,_&x1Z
public String getCountType(){ s]U4B<q
return countType; #(C/Cx54
} 0rD#s{?
public int getCountId(){ Nl@k*^
return countId; #G_F`&
} z3a-+NjD m
} OifvUTl9b
ueDvMP
CountCache.java bAf,aV/C&|
$X*mdji
/* GnFs63
* CountCache.java \m4T3fy
* |; $Bb866/
* Created on 2007年1月1日, 下午5:01 ?aBj#
* %}q.cV
* To change this template, choose Tools | Options and locate the template under Z%}4bJ
* the Source Creation and Management node. Right-click the template and choose \fZiL!E^7
* Open. You can then make changes to the template in the Source Editor. )6{<
i5nJ\
*/ uWjN2#&,
wu)Wg-dT
package com.tot.count; ]H ~Y7\N-v
import java.util.*; nnwJYEi
/** xRum*}|4
* Qzqc .T
* @author hQRL,?
*/ Z) Wnow
public class CountCache { ACg;CTBb
public static LinkedList list=new LinkedList(); h}Rx_d
/** Creates a new instance of CountCache */ zI^]esX!2_
public CountCache() {} yto[8;)_
public static void add(CountBean cb){ k$N0lR4:p
if(cb!=null){ g #
S0V
list.add(cb); %'bJ:
} %{!R
l@
} {E A1vo"
} xCXQ<77
nv0#~UgE#a
CountControl.java \OQkZ.cU;
1vnYogL
/* .5w azvA
* CountThread.java !E2W\chi
* D3D}DaEYj
* Created on 2007年1月1日, 下午4:57 aI3CNeav
* h|D0z_f
* To change this template, choose Tools | Options and locate the template under }^xE|~p
* the Source Creation and Management node. Right-click the template and choose +1rkq\{l
* Open. You can then make changes to the template in the Source Editor. : g6n,p_#
*/ _,haD)1g~
Kcy@$uF{2
package com.tot.count; DF_X
import tot.db.DBUtils; Z
hd#:d
import java.sql.*; ,WDX(
/** jQS 6J+F]
* _%/}>L>-`8
* @author wSEWwU[
*/ j8Cho5C
public class CountControl{ k*?I>%^6#T
private static long lastExecuteTime=0;//上次更新时间 nXy>7H[0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 b[I8iS kfi
/** Creates a new instance of CountThread */ A1"SLFY
public CountControl() {} OsqNB'X
public synchronized void executeUpdate(){ |'d>JT:
Connection conn=null; xtfBfA
PreparedStatement ps=null; bq>_qpr
try{ W,XTF
conn = DBUtils.getConnection(); >w+HHs/$wK
conn.setAutoCommit(false); 1v zb8.
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Lfog
{Vzs
for(int i=0;i<CountCache.list.size();i++){ H+E$:)gN
CountBean cb=(CountBean)CountCache.list.getFirst(); #bH_Dg5I
CountCache.list.removeFirst(); T 20&F
ps.setInt(1, cb.getCountId()); <-'$~G j
ps.executeUpdate();⑴ I,yC
D7l_
//ps.addBatch();⑵ /D!;u]
} */:uV
B,b2
//int [] counts = ps.executeBatch();⑶ z2_6??tS/c
conn.commit(); km~Ll
}catch(Exception e){ [NMVoBvG
e.printStackTrace(); 7%f&M>/
} finally{ tW
WWx~k
try{ (T`E!A0I\?
if(ps!=null) { v~QHMg
ps.clearParameters(); *Kdda}
J+
ps.close(); C|pdv
ps=null; svxw^0~a
} /xtq_*I1S
}catch(SQLException e){} 'AN>`\mR$
DBUtils.closeConnection(conn); fhL,aCS=
} C8
\5A8c
} }=c85f~i
public long getLast(){ ]a5 f2lE
return lastExecuteTime; 1UPC e
} pe^u$YE
public void run(){ eek7=Z
long now = System.currentTimeMillis(); UQ{L{H
if ((now - lastExecuteTime) > executeSep) { :POj6j/
//System.out.print("lastExecuteTime:"+lastExecuteTime); phM>.y_
//System.out.print(" now:"+now+"\n"); (sh)TBb5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); H\TI[JPAl
lastExecuteTime=now; |PC*=ykT3
executeUpdate(); 1t)il^p4[;
} FCnm1x#
else{ tQS5hwm*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /`mks1:pK
} I:mr}mv=i
} \[y`'OD~
} gLOEh6
//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 Hv2De0W
@nux9MX<9
类写好了,下面是在JSP中如下调用。 Uu `9"
E{|W(z,
<% r-Pkfy(
CountBean cb=new CountBean(); YJ\Xj56gv
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); RJd(~1
CountCache.add(cb); Q\ 0cvmU
out.print(CountCache.list.size()+"<br>"); 9b9$GyI
CountControl c=new CountControl(); XT4{Pe7{[P
c.run(); T\D}kQM
out.print(CountCache.list.size()+"<br>"); 7eAX*Kgt<_
%>