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: 9lkl-b6xG
k9&W0$I#
CountBean.java 4tvZJS
hV
:c(I-xif
/* dsK*YY jH
* CountData.java ;Y`8Ee4vH
* !u/c'ZLZ>
* Created on 2007年1月1日, 下午4:44 i-4?]h k
*
CUft
* To change this template, choose Tools | Options and locate the template under %6&c3,?U\n
* the Source Creation and Management node. Right-click the template and choose &KV$x3
* Open. You can then make changes to the template in the Source Editor. B- |C%~fe
*/ M"Z/E>ne
H2+V1J=
package com.tot.count; _UbyhBl
ACI.{`SrQ=
/** ?\<Kb|Q
* zs'Jgm.v
* @author H1
i+j;RN
*/ Y~I0\8s-
public class CountBean { cet|k!
private String countType; d_&~^*>
int countId; <d[GGkY]=
/** Creates a new instance of CountData */ $ dKo}
public CountBean() {} E};1
H
public void setCountType(String countTypes){ 4KW_#d`t
this.countType=countTypes; >keYx<1
} ']H*f2y
public void setCountId(int countIds){ +JB*1dz>8
this.countId=countIds; Wi*HLP!lNC
} RGBntp%
public String getCountType(){ `2j"Z.=
return countType; 3qDuF
} D}2$n?~+
public int getCountId(){ <AHdz/N
return countId; v5FfxDvw
}
:Z6l)R+V
} {axRq'=
ApcE)mjpc
CountCache.java ^~3{n
!F2JT@6
/* kPSi6ci
* CountCache.java >^v,,R8j
* bV*q~@xh
* Created on 2007年1月1日, 下午5:01
B"t4{1/
* z:08;}t
* To change this template, choose Tools | Options and locate the template under !1<>][F
* the Source Creation and Management node. Right-click the template and choose JP]-a!5Ru
* Open. You can then make changes to the template in the Source Editor. 8vj]S5
*/ aOEW$%
l 1BAW$
package com.tot.count; qIO)<5\[%d
import java.util.*; ;F/s!bupCM
/** xoQqku"vn
* iH-(_$f;
* @author BbgKaC q
*/ I=k`VI d:
public class CountCache { |jKFk.M
public static LinkedList list=new LinkedList(); 2p*L~! iM
/** Creates a new instance of CountCache */ B^j(Fq
public CountCache() {} WmblY2
public static void add(CountBean cb){ vs*@)'n0 }
if(cb!=null){ xz}=C:s
list.add(cb); kP&Ekjt@
} Ft @ZK!'@
} yq` ,)
} `CG% Y>+
prGp/"E
CountControl.java q=k[]vD
:eSwXDy&
/* KPa@~rU
* CountThread.java - ysd`&
* raZ0B,;eFu
* Created on 2007年1月1日, 下午4:57 )+a]M1j
* T6=~vOzTJ
* To change this template, choose Tools | Options and locate the template under <7j"CcJzZ
* the Source Creation and Management node. Right-click the template and choose K3`48,`?wA
* Open. You can then make changes to the template in the Source Editor. l YjPrA]TC
*/ ?'OL2~
7K/t>QrBtU
package com.tot.count; (2/i1)Cq
import tot.db.DBUtils; }G<A$*L1
import java.sql.*; T>v`UN Bl]
/** }vW3<|z
* (y2P."
* @author ::Pf\Lb>
*/ sP%J`L@h
public class CountControl{ eS2VLVxu
private static long lastExecuteTime=0;//上次更新时间 wOR#sp&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 FNXVd/{M3
/** Creates a new instance of CountThread */ ]iaQD _'\
public CountControl() {} (9+N_dLx~P
public synchronized void executeUpdate(){ r6e!";w:U
Connection conn=null; ZRC7j?ui8`
PreparedStatement ps=null; 4Gsq)i17j
try{ S{~j5tQv^q
conn = DBUtils.getConnection(); lp5b&I_
conn.setAutoCommit(false); P}D5 j
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); sV`XJ9e|
for(int i=0;i<CountCache.list.size();i++){ Aoy=gK
CountBean cb=(CountBean)CountCache.list.getFirst(); zi,":KDz#
CountCache.list.removeFirst(); qjIcRue'"
ps.setInt(1, cb.getCountId()); TA+/35^?
ps.executeUpdate();⑴ <}AmzeHr+
//ps.addBatch();⑵ OJ}aN>k
} ypY7uYO^"
//int [] counts = ps.executeBatch();⑶ %?z;'Y7D
conn.commit(); L$}'6y/@
}catch(Exception e){ oRl@AhS
e.printStackTrace(); @Hst-H.l<l
} finally{ +/Vzw
try{ BWsD~Ft
if(ps!=null) { bpfSe
ps.clearParameters(); @C5%`{\
ps.close(); 4,ewp coC%
ps=null; s;:quM
} 4?~Ei[KgQn
}catch(SQLException e){} d6"B_,*b
DBUtils.closeConnection(conn); E>qe hs,g
} cONfHl{
} `aaT
#r
public long getLast(){ .%mjE'
return lastExecuteTime; i-&"1D[&
} H=5#cPI#(^
public void run(){ 6
ZVD<C :\
long now = System.currentTimeMillis(); |(R[5q
if ((now - lastExecuteTime) > executeSep) { ZRCUM"R_
//System.out.print("lastExecuteTime:"+lastExecuteTime); %l)~C%T
//System.out.print(" now:"+now+"\n"); r A9Rz^;xa
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9!Vp-bo
lastExecuteTime=now; b]\V~ZaXG
executeUpdate(); ~Nl`Zmn(A|
} aB4L$M8x
else{ @#| R{5=+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); F2["Ak NM
} Rj,M|9Y)o
} (OHd} YQ
} n`7n5M*
//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 ,NQ>,}a0
x:IY6 l
类写好了,下面是在JSP中如下调用。 u2Qs}FX
/4u:5G
<% 8\8%FSrc
CountBean cb=new CountBean(); w7h=vy n?
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); AmT*{Fz8
CountCache.add(cb); tqK}KL
out.print(CountCache.list.size()+"<br>"); 2&U<Wiu\}
CountControl c=new CountControl(); Px"K5c*
c.run(); pXHeUBY.
out.print(CountCache.list.size()+"<br>"); &E8fd/s=k
%>