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: XOZ@ek)LY
rqM_#[Y?
CountBean.java NCx)zJ\S
^X*l&R_=R
/* @jr$4pM?
* CountData.java ;4vx+> -
* ?l
0WuU
* Created on 2007年1月1日, 下午4:44 Nu; 9
* ub{Yg5{3S\
* To change this template, choose Tools | Options and locate the template under \D! I"mr
* the Source Creation and Management node. Right-click the template and choose g+k
yvI7o
* Open. You can then make changes to the template in the Source Editor. Ys%d
*/ x1`Jlzrp,
~HX'8\5
package com.tot.count; aFy'6c}
]@msjz'
/** ZN`I4Ak
* XCO;t_%
* @author V#-8[G6Ra
*/ 4L2TsuLw
public class CountBean { lHgmljn5u
private String countType; ]u
>~:
int countId; `[4{]jX+<
/** Creates a new instance of CountData */ )9rJ]D^B
public CountBean() {} DM !B@
public void setCountType(String countTypes){ yu'@gg(
this.countType=countTypes; O/f+B}W
} Ar$Am
public void setCountId(int countIds){ y-:d`>b>\
this.countId=countIds; (M t-2+"+
} f@xjNm*'Z
public String getCountType(){ K~\Ocl
return countType; i"y @Aj!7
} :AC( \
public int getCountId(){ j{NcDepLn
return countId; %y\
} gs= (h*
} <~.1>CI9D3
k Rp$[^ma
CountCache.java }$'T=ay&
6.QzT(
/* .u9,w
* CountCache.java 0qo:M3
* D +9l$**a
* Created on 2007年1月1日, 下午5:01 *f+DV[DF
* <a%RKjQvT
* To change this template, choose Tools | Options and locate the template under {c AGOx wd
* the Source Creation and Management node. Right-click the template and choose 8<X;
8R
* Open. You can then make changes to the template in the Source Editor. b,RQ" {
*/ P?YcZAJT*
IaR D"oCH
package com.tot.count; :.fm LL
import java.util.*; xAAwH@ +
/** USyOHHPW@
* 69{q*qCW
* @author vHx[:vuq:
*/ A]s|"Pav,
public class CountCache { ^9?IS<N0]
public static LinkedList list=new LinkedList(); p#AQXIF0
/** Creates a new instance of CountCache */ Wr\A ->+
public CountCache() {} ;Z{jol
public static void add(CountBean cb){ sb*)K,U
if(cb!=null){ =E-V-?N\
list.add(cb); ]9NA3U7F
} `KmM*_a
} ~~3 BV,
} xEqr3(
:PDyc(s{
CountControl.java E(Y}*.\]#s
XlU`jv+
/* W v!%'IB
* CountThread.java ]*vv=@"`e
* 4xD`Z_U
* Created on 2007年1月1日, 下午4:57 59M\uVWR
* a}/ A]mu
* To change this template, choose Tools | Options and locate the template under 8{4jlL;"`?
* the Source Creation and Management node. Right-click the template and choose }:hN}*H
* Open. You can then make changes to the template in the Source Editor. /}$D&KwYg
*/ 7y'2
PFPZ]XI%F
package com.tot.count; J`d;I#R%c
import tot.db.DBUtils; ._US8
import java.sql.*; +I r
/** YS+|n%?
* zqa7!ky
* @author FWDAG$K@0
*/ C{U"Nsu+1
public class CountControl{ jk fc=O6^
private static long lastExecuteTime=0;//上次更新时间 RD0=\!w *5
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8(""ui8
/** Creates a new instance of CountThread */ pt=H?{06
public CountControl() {} QL`Hb p
public synchronized void executeUpdate(){ qjmlwVw
Connection conn=null; *VgiJ
PreparedStatement ps=null; C0 %yGLh&
try{ SK;c
D>)
conn = DBUtils.getConnection(); Q6rvTV'vv
conn.setAutoCommit(false); R*r;`x
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @pO2A6Ks
for(int i=0;i<CountCache.list.size();i++){ 4|Ay;}X \
CountBean cb=(CountBean)CountCache.list.getFirst(); #8qhl
CountCache.list.removeFirst(); U/9_:
ps.setInt(1, cb.getCountId()); \*5${[
ps.executeUpdate();⑴ 8t
>nL
//ps.addBatch();⑵ bE>"DPq
} :pvJpu$]
//int [] counts = ps.executeBatch();⑶ 9B?-&t
conn.commit(); .I
nDyKt
}catch(Exception e){ %,Lv},%Y
e.printStackTrace(); |58xR.S'g
} finally{ 20A`]-D
try{ /mCE=
if(ps!=null) { i-gN<8\v
ps.clearParameters(); G#nZ%qQ:I
ps.close(); ~X!Z+Vg
ps=null; _mc-CZ
} {Etvu
}catch(SQLException e){} yttaZhK^u
DBUtils.closeConnection(conn); kBg8:bo~
} aGq1YOD[$
} q1?}G5a?
public long getLast(){ :B
9>
return lastExecuteTime; p;n"zr8U
} Tqj:C8K{
public void run(){ D,P{ ,/
long now = System.currentTimeMillis(); JK'FJ}Z4
if ((now - lastExecuteTime) > executeSep) { l~Rd\.O
//System.out.print("lastExecuteTime:"+lastExecuteTime); yr/G1?k%ML
//System.out.print(" now:"+now+"\n"); X)b@ia'"Wp
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7B{LRm6;Vu
lastExecuteTime=now; d=d*:<Zx
executeUpdate(); 7oV$TAAf
} P+bA>lJd
else{ !!?TkVyEyM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~EtwX YkRZ
} x>$e*
} ]+A%37
} Wmc@:
(n
//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 p(Ux]_s%
\45F;f_r6
类写好了,下面是在JSP中如下调用。 bYAtUEv
.W
s\%S
<% w;;9YFBdM
CountBean cb=new CountBean(); 6W[~@~D=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); g0ks[ }f-
CountCache.add(cb); XR|U6bf]
out.print(CountCache.list.size()+"<br>"); Gy)2
CountControl c=new CountControl(); D$Eq~VQ
c.run(); /odDJxJ
k
out.print(CountCache.list.size()+"<br>"); .bY
R
%>