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: GtZ.'?-
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CountBean.java v;;3 K*c>
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/* CZeZk
* CountData.java `Z5dRLrd
* mR
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* Created on 2007年1月1日, 下午4:44 x`@`y7(
* $)o0{HsL+
* To change this template, choose Tools | Options and locate the template under Mz2TwU_
* the Source Creation and Management node. Right-click the template and choose JJbd h \
* Open. You can then make changes to the template in the Source Editor. g.hYhg'KUh
*/ {GnZ@Q:F
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package com.tot.count; 2/s42
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/** (g X8iKl
* WR"1d\m:
* @author :0 n+RL*5
*/ N5sVRL"7
public class CountBean { GxG~J4
private String countType; L;j++^p
int countId; L2EQ 9i'[
/** Creates a new instance of CountData */ C5TV}Bq\
public CountBean() {} @d 7V@F0d
public void setCountType(String countTypes){ c$&({Z{1
this.countType=countTypes; Fih
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} Ow4(1eE_
public void setCountId(int countIds){ Gvh"3|u?z
this.countId=countIds; /P TRe5-7
} T9Juq6|
public String getCountType(){ $S?gQN.e
return countType; <Ohi+a%6
} r#)1/`h
public int getCountId(){ rg >2tgA
return countId; kln)7SzPuk
} vVa|E#
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} ZnI15bsDx
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CountCache.java E/%"%&`8j
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/* 1Pw1TO"Z
* CountCache.java $>O~7Nfst7
* }a~hd*-#
* Created on 2007年1月1日, 下午5:01 6Nn+7z<*&z
* =VuSi(d;e{
* To change this template, choose Tools | Options and locate the template under p5or"tK
* the Source Creation and Management node. Right-click the template and choose M;ADL|
* Open. You can then make changes to the template in the Source Editor. GK'p$`oJm
*/ LPJ7V`!k
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package com.tot.count; FV
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import java.util.*; 4FRi=d;mP
/** -X$EE$:
* ([<HFc`
* @author \b(&-=(
*/ Wmcd{MOS
public class CountCache { EC,`t*<
public static LinkedList list=new LinkedList(); MU
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/** Creates a new instance of CountCache */ QE[<Y3M
public CountCache() {} .aY$-Y<
public static void add(CountBean cb){ !KK `+ 9/
if(cb!=null){ Y 2ANt w@
list.add(cb); I)FFh%m<}a
} /^nIOAeE
} OR~ui[w
} fy"}#
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CountControl.java Sf*v#?
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/* S5TVfV5LI
* CountThread.java 04|ZwX$>+
* l|gi2~ %Y
* Created on 2007年1月1日, 下午4:57 ,k4pW&A
* =+j3E<w
* To change this template, choose Tools | Options and locate the template under BK%B[f*[OA
* the Source Creation and Management node. Right-click the template and choose \/3(>g?4
* Open. You can then make changes to the template in the Source Editor. BM /FOY;
*/ [h;I)ug[o(
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package com.tot.count; 23^>#b7st
import tot.db.DBUtils; C'$}{%Cc@$
import java.sql.*; 'A:Y&w"r
/** :\"0jQ.y|
* G'/GDN^j
* @author +M
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*/ 4DCh+|r
public class CountControl{ _<.VP
private static long lastExecuteTime=0;//上次更新时间 8~C}0H
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 }bS1M
/** Creates a new instance of CountThread */ \]Ah=`
public CountControl() {}
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public synchronized void executeUpdate(){ /)_4QSz7
Connection conn=null; nA,=g'7S
PreparedStatement ps=null; SQcic]Ep
try{ "73y}'
conn = DBUtils.getConnection(); C+s/KA%
conn.setAutoCommit(false); X#$ oV#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %(eQ1ir +
for(int i=0;i<CountCache.list.size();i++){ =figat
CountBean cb=(CountBean)CountCache.list.getFirst(); G`0O5G:1
CountCache.list.removeFirst(); <9fXf*
ps.setInt(1, cb.getCountId()); AEyD?^?
ps.executeUpdate();⑴ x7zc3%T's
//ps.addBatch();⑵ ]z^jz#>um&
} cl^UFlf[
//int [] counts = ps.executeBatch();⑶ V[/9?5pM
conn.commit(); 06.%9R{
}catch(Exception e){ N+c|0
e.printStackTrace(); q%;cu1^"M
} finally{ qK%N{ro[{?
try{ n&;JW6VQS
if(ps!=null) { G=17]>U
ps.clearParameters(); ;
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ps.close(); [#gm[@d,
ps=null; Pt5 wm\
} x/<]/D
}catch(SQLException e){} /r~2KZE
DBUtils.closeConnection(conn); $mGzJ4&
} Bn&P@C$7
} |9S8sfw
public long getLast(){ {k.:DH)
return lastExecuteTime; $EFS_*<X
} i;%G Z8
public void run(){ #h=V@Dh
long now = System.currentTimeMillis(); HU?1>}4L
if ((now - lastExecuteTime) > executeSep) { j13-?fQ&
//System.out.print("lastExecuteTime:"+lastExecuteTime); mU4(MjP?
//System.out.print(" now:"+now+"\n"); RG45S0Ygj
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); lF(v<drkB
lastExecuteTime=now; j67a?0<C2U
executeUpdate(); 9y6u&!PZ\
} qWr=Oiu
else{ _)5E=
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &qXobJRM
} md{nHX&
} <T[LugI
} )'n@A% B
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 rogy`mh\r2
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类写好了,下面是在JSP中如下调用。 vOlfyH>
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<% m=9b/Nr4
CountBean cb=new CountBean(); RM_%u=jC
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9)tb=
CountCache.add(cb); _\+]/rY9o
out.print(CountCache.list.size()+"<br>"); UiV#w#&P
CountControl c=new CountControl(); KU$,{Sn6@
c.run(); 3<XuJ1V&
out.print(CountCache.list.size()+"<br>"); "7%jv[
%>