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: 39~fP)
%@pTEhpF
CountBean.java hb?
|fi
;?n*w+6<
/* Y71b
Lg
* CountData.java *q8W;WaL
* 7Jc=`Zm'
* Created on 2007年1月1日, 下午4:44 /I6?t=?<
* by8d18:it
* To change this template, choose Tools | Options and locate the template under B8a!"AQ~5
* the Source Creation and Management node. Right-click the template and choose Aoa0czC~
* Open. You can then make changes to the template in the Source Editor. #axRg=d?K
*/ ZU "y<
6[qRb+ds
package com.tot.count; ^ /g&Q
70KXBu<6
/** ,&)XhO?
* sBSBDjk[
* @author jl:O~UL6i
*/ xsAF<:S\
public class CountBean { dc lJ
private String countType; w_|WberU
int countId; $L`7(0U-
/** Creates a new instance of CountData */ ) mv}u~
public CountBean() {} p1Lx\
public void setCountType(String countTypes){ oM MU5sm
this.countType=countTypes; 2]4R`[#
} MX9q
)(:
public void setCountId(int countIds){ >Zmpsa+
this.countId=countIds; WtlIrdc
} 53(m9YLk
public String getCountType(){ 0/] @#G2
return countType; fylaH(LER
} yUH8
public int getCountId(){ x$s #';*
return countId; rxDule3m
} 4Nq n47|>e
} 0!(Ii@m=N
%8 4<@f&n]
CountCache.java 1p8E!c{}j
q2/Vt0aYx
/* XUSfOf(
* CountCache.java /!%P7F
* {[Yv@CpN
* Created on 2007年1月1日, 下午5:01 E+ 7S:B
* C %EQ9Iq6r
* To change this template, choose Tools | Options and locate the template under ff:&MsA|,
* the Source Creation and Management node. Right-click the template and choose I=3q#^}[
* Open. You can then make changes to the template in the Source Editor. 1W/=
=+%I
*/ F48`1+
@cjhri|vH
package com.tot.count; UT^t7MY#O
import java.util.*; Dri1A%
/** }xdI{E1 q)
* BO{J{
* @author {{<o1{_H
*/ Z;n}*^U
public class CountCache { 2r*
o
public static LinkedList list=new LinkedList(); 0kiW629o
/** Creates a new instance of CountCache */ !HB,{+25
public CountCache() {} :*oI"U*f
public static void add(CountBean cb){ 'Y&yt"cs
if(cb!=null){ :'rXu6c-
list.add(cb); ucA6s:!={
} e=F'
O]
5
} L50`,,WF
} FS@SC`~(
m&$H?yXW>
CountControl.java |"@E"Za^
#Xn#e
/* :))AZ7_
* CountThread.java R=9j+74U
* 9#3+k/A
* Created on 2007年1月1日, 下午4:57 f0^s*V+
* {)%B?75~
* To change this template, choose Tools | Options and locate the template under s!+?)bB
* the Source Creation and Management node. Right-click the template and choose YTGup]d
* Open. You can then make changes to the template in the Source Editor. 6%yr>BFtVV
*/ 9(@bjL465
4XKg3l1
package com.tot.count; `9wz:s QtP
import tot.db.DBUtils; |H@M-
import java.sql.*; aFC3yMKXh
/** Z]Qm64^I
* >T(f
* @author m|-O/6~
*/ [&zP$i&
public class CountControl{ `i.f4]r
private static long lastExecuteTime=0;//上次更新时间 fIBLJ53
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 x[>A'.m@)
/** Creates a new instance of CountThread */ ]&9f:5',
public CountControl() {} O Ov"h\,
public synchronized void executeUpdate(){ {`3;Pd`
Connection conn=null; N.&K"J
PreparedStatement ps=null; H?aB8=)
try{ Cu`ZgKLQ
conn = DBUtils.getConnection(); I&cb5j]C
conn.setAutoCommit(false); \XpPb{:>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P!vBS"S
for(int i=0;i<CountCache.list.size();i++){ e~-Dk .i
CountBean cb=(CountBean)CountCache.list.getFirst(); Dgkt-:S/T|
CountCache.list.removeFirst(); '17=1\Ss6;
ps.setInt(1, cb.getCountId()); B@s\>QMm
ps.executeUpdate();⑴ {2q
//ps.addBatch();⑵ @lmk e>
} h`vM+,I
//int [] counts = ps.executeBatch();⑶ qGh rJ6R!
conn.commit(); ;=n7 Z
}catch(Exception e){ 0<s)xaN>Y
e.printStackTrace(); =W4cWG?+
} finally{ AOfQqGf
try{ Lc.7:r
if(ps!=null) { K]7@%cS
ps.clearParameters(); pa\]@;P1
ps.close(); ^L'K?o
ps=null; lLg23k{'
} $GPA6
}catch(SQLException e){} i\<l&W
DBUtils.closeConnection(conn); i/$lOde
} =djzE`)0
} A] F K\
public long getLast(){ )q=1<V44d
return lastExecuteTime; QUe.vb^O
} +V'Z%;/
public void run(){ 5fLCmLM`
long now = System.currentTimeMillis(); 2N]y)S_<V
if ((now - lastExecuteTime) > executeSep) { r`&ofk1K
//System.out.print("lastExecuteTime:"+lastExecuteTime); kNjbpCE\!
//System.out.print(" now:"+now+"\n"); V~+Unn
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); -\I0*L'$|\
lastExecuteTime=now; /qp`xJ
executeUpdate(); grS,PKH
} ?(|!VLu
else{ *r %
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6-JnT_
} G?"1
z;
} gr2zt&Z4
} J]~3{Mi
//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 &/zsIx+
'WOWm$2
类写好了,下面是在JSP中如下调用。 62zlO{ >rJ
3oIoQj+D
<% w5[POo' 5
CountBean cb=new CountBean(); e)iVX<qb
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <D 5QlAN
CountCache.add(cb); hrW.TwK
out.print(CountCache.list.size()+"<br>"); :,7VqCh3@
CountControl c=new CountControl(); i@p?.%K{
c.run(); I#mT#xs6
out.print(CountCache.list.size()+"<br>"); /!E /9[V
%>