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: `({Bi!%i
6 *GR_sMm
CountBean.java Ks>l=5~v|
S5(VdMd"^
/* iKVJ
c=C
* CountData.java t~0!K;nn
*
<}
BuU!
* Created on 2007年1月1日, 下午4:44 k7cM.<s!
* (=eJceE!
* To change this template, choose Tools | Options and locate the template under P
=jRof$
* the Source Creation and Management node. Right-click the template and choose :5DL&,,Q3
* Open. You can then make changes to the template in the Source Editor. ":meys6t#
*/ Gkr?M^@K
\kS:u}Ip!
package com.tot.count; oz[Mt
i*
H-g
CY|W
/** +WTO_J7
* qH9bo-6
* @author )a=58r07
*/ qZwqnH
public class CountBean { tSf$`4
private String countType; :g~X"C1s
int countId; TaqqEL
/** Creates a new instance of CountData */ DKnlbl1^?
public CountBean() {} rQLl[a
public void setCountType(String countTypes){ [~v1
this.countType=countTypes; 9:v0gE+.
} K4w#}gzok
public void setCountId(int countIds){ N7l`-y
this.countId=countIds; <uKd)l
} ZdsYIRU#
public String getCountType(){ W3E7y?
return countType; h|Ah\P?o
} cqSo%a2
public int getCountId(){ NSV;R~"
return countId; gZ W(z
} >gSiH#>
} 7mT
iO?/y<
`ttqgv\
CountCache.java {Yc#XP
tMDJ,rT
/* 6!T9VL\=H
* CountCache.java 41XS/# M$*
* :oeDksld
* Created on 2007年1月1日, 下午5:01 ~C31=\$
* |1/UC"f
* To change this template, choose Tools | Options and locate the template under ;%`oS.69
* the Source Creation and Management node. Right-click the template and choose ;_dOYG1
* Open. You can then make changes to the template in the Source Editor. TO5#iiM)
*/ (`cXS5R
!V O^oD7
package com.tot.count; 'L5ih|$>
import java.util.*; oQL$X3S
/** s.IYPH|pn
* G4jyi&]
* @author WFm\ bZ.
*/ =#so[Pd
public class CountCache { Bid+,,
public static LinkedList list=new LinkedList(); F[5sFkM7
/** Creates a new instance of CountCache */ 7)zF8V
public CountCache() {} xN +Oca
public static void add(CountBean cb){ 3[r9v!l
if(cb!=null){ {"vTaY@
list.add(cb); Bbj%RF2,
} !3;KC"o
} jM5w<T-2/
} MY w3+B+Jj
2AdO
CountControl.java )C&'5z
|x+g5~$
/* YW7Pimks
* CountThread.java r-8fvBZ5
* (CR]96n
* Created on 2007年1月1日, 下午4:57 kD\7wz,ui
* h#~\-j9>
* To change this template, choose Tools | Options and locate the template under Qk[YF
* the Source Creation and Management node. Right-click the template and choose 08MY=PC~R
* Open. You can then make changes to the template in the Source Editor. U.A:'9K,
*/ d9Uv/VGp
N_liKhq
package com.tot.count; ~m6b6Aj@6
import tot.db.DBUtils; ttd
^jT
import java.sql.*; #gc v])to
/** \u$[ $R5
* FnWN]9
* @author %/}46z9\
*/ mz m{p(.
public class CountControl{ von<I
private static long lastExecuteTime=0;//上次更新时间 ,vcd>"PK
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 y{g"w
/** Creates a new instance of CountThread */ wmDO^}>ZP
public CountControl() {} 59#o+qo4
public synchronized void executeUpdate(){ _uq[D`=
Connection conn=null; }MIg RQ9
PreparedStatement ps=null; X0 ^~`g
try{ EN/r{Cm$B
conn = DBUtils.getConnection(); 1%$Z%?
conn.setAutoCommit(false); i TLX=.M
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); KbGz3O'u
for(int i=0;i<CountCache.list.size();i++){ Ux-i iH#s
CountBean cb=(CountBean)CountCache.list.getFirst(); S.R|Bwj}(Y
CountCache.list.removeFirst(); :ZsAWe{%,J
ps.setInt(1, cb.getCountId()); sL4j@Lt
ps.executeUpdate();⑴ xRbtiFk9H
//ps.addBatch();⑵ yN{TcX
} Csf!I@}Z
//int [] counts = ps.executeBatch();⑶ M97MIku~9
conn.commit(); vX}#wDNP
}catch(Exception e){ <^(>o
e.printStackTrace(); *n x$r[Mqj
} finally{ V {C{y5
try{ 5*\]F}
if(ps!=null) { t|?eNKVV9'
ps.clearParameters(); V:
n\skM
ps.close(); r) g:-[Ox9
ps=null; FSD~Q&9&
} F10TvJ
U
}catch(SQLException e){} [9d4 0>e
DBUtils.closeConnection(conn); `Rx\wfr}
} _V,bvHWlM
} \\P*w$c
public long getLast(){ $!7$0WbC
return lastExecuteTime; C$4!|Wg3
} BFswqp:
public void run(){ a)QSq<2*
long now = System.currentTimeMillis(); 8 -YC#&
if ((now - lastExecuteTime) > executeSep) { !rTkH4!_
//System.out.print("lastExecuteTime:"+lastExecuteTime); })umg8s
//System.out.print(" now:"+now+"\n"); Vb,'VN%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); x(7Q5Uk\
lastExecuteTime=now; td 5!
S]
executeUpdate(); C;I:?4
} ^tY
_ q
else{ 3YD.Fjz$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); xQDWnpFc
} #<DS-^W!
} .~,=?aq^
} -T2w?|
//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 O"~CZh,:r}
u$<>8aMei
类写好了,下面是在JSP中如下调用。 ZVz`g]
Eg(.L,dj
<% |+Cd2[hN
CountBean cb=new CountBean(); )1gOO{T]h?
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0y`r.)G
CountCache.add(cb); w5`EJp8MC
out.print(CountCache.list.size()+"<br>"); `Sal-|[Cv[
CountControl c=new CountControl(); & ^;3S*p
c.run(); o[%\W
out.print(CountCache.list.size()+"<br>"); ?$.JgG%Z+g
%>