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: :t]HY2
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CountBean.java -g]Rs!w'
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/* m&Mupl
* CountData.java +ti ?7|bK<
* j
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* Created on 2007年1月1日, 下午4:44 b1.*cIv}
* w_xca(
* To change this template, choose Tools | Options and locate the template under ~DI$O[KpR%
* the Source Creation and Management node. Right-click the template and choose :Iv;%a0 -
* Open. You can then make changes to the template in the Source Editor. UnF8#~
*/ "(^XZAU#W
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package com.tot.count; "|L"C+tE
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/** a+E&{pV
* Ki2!sADd
* @author UtQey ;w
*/
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public class CountBean { *[3xc*5F/A
private String countType; >H!Mx_fDL
int countId; )rD!4"8/A
/** Creates a new instance of CountData */ V@G#U[D
public CountBean() {} N8b\OTk2
public void setCountType(String countTypes){ fI613ww]
this.countType=countTypes; K Lg1(W(
} 3}0\W.jH
public void setCountId(int countIds){ `za,sRFR
this.countId=countIds; Sw\*$g]
} ]R#:Bq!F
public String getCountType(){ ~ELMLwn.
return countType; [|DKBJ
} 8AuBs;i
public int getCountId(){ #]kjyT0
return countId; ttzNv>L,
} aa`(2%(:
} ej`%}e%2
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CountCache.java t'rN7.d
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/* _\}'5nmw\
* CountCache.java d,V#5l-6
* 4Z( #;9f
* Created on 2007年1月1日, 下午5:01 ^dHQ<L3.*
* N1c=cZDV
* To change this template, choose Tools | Options and locate the template under z1PwupXt1
* the Source Creation and Management node. Right-click the template and choose <Kd(fFe
* Open. You can then make changes to the template in the Source Editor. Q +^&
*/ V&M*,#(?
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package com.tot.count; =?<WCR
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import java.util.*; `Vb
/** 3@>F-N
* `6D?te
* @author dAh.I3
*/ {LO Pm1K8Y
public class CountCache { r9i?H
public static LinkedList list=new LinkedList(); ;]>kp^C#
/** Creates a new instance of CountCache */ E-bswUVaEE
public CountCache() {} z)qYW6o%
public static void add(CountBean cb){ tS'lJu
if(cb!=null){ / (&E
list.add(cb); _FY&XL=
} Fb5U@X/vE
} &O&HczO
} k$w~JO!s
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CountControl.java 6#?T?!vZ
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/* rs&]46i/p
* CountThread.java H_DCdUgC'
* K p3}A$uV
* Created on 2007年1月1日, 下午4:57 za>UE,?h
* t]yxLl\
* To change this template, choose Tools | Options and locate the template under OXEk{#Uf[3
* the Source Creation and Management node. Right-click the template and choose zUfq.
* Open. You can then make changes to the template in the Source Editor. uJ!&T
*/ =}^NyLE?
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package com.tot.count; Jl
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import tot.db.DBUtils; >
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import java.sql.*; 9u B?-.
/** :!`"GaTy
* Da=EAG-{7
* @author Mt[yY|Ec|
*/ XE}gl&\
public class CountControl{ kRp]2^}\s\
private static long lastExecuteTime=0;//上次更新时间 ~MC|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 k ut=(;
/** Creates a new instance of CountThread */ CRb8WD6.
public CountControl() {} :xh{SsW@
public synchronized void executeUpdate(){ WE<?y_0y&
Connection conn=null; N9e'jM>Oos
PreparedStatement ps=null; !#tVQ2O
try{ &`"DG$N(
conn = DBUtils.getConnection(); IC`3%^
conn.setAutoCommit(false); diq}\'f
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); D'"
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for(int i=0;i<CountCache.list.size();i++){ 51#*8u+L
CountBean cb=(CountBean)CountCache.list.getFirst(); $
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CountCache.list.removeFirst(); SK<Rk
ps.setInt(1, cb.getCountId()); n
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ps.executeUpdate();⑴ v, $r.g;
//ps.addBatch();⑵ O\5%IfB'"
} Ot=jwvw
//int [] counts = ps.executeBatch();⑶ #@XBHJD\#
conn.commit(); 7aG.?Ca%
}catch(Exception e){ "s2_X+4oY
e.printStackTrace(); OxlA)$.hpu
} finally{ ;FPx
try{ Pf*6/7S:
if(ps!=null) { D tsZP
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ps.clearParameters(); I= mz^c{
ps.close(); M&Uy42,MR
ps=null; w+M/VsL
} mxa~JAlN_
}catch(SQLException e){} *$tXm4
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DBUtils.closeConnection(conn); 3<0b_b
} )DSeXS[
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} +>ju,;4WK
public long getLast(){ fqNh\~kja
return lastExecuteTime; ( xs'D4
} pGbfdX
public void run(){ !ifU}qFzK
long now = System.currentTimeMillis(); DeO-@4+qKd
if ((now - lastExecuteTime) > executeSep) { ;Rrh$Ag
//System.out.print("lastExecuteTime:"+lastExecuteTime); P}bIp+
//System.out.print(" now:"+now+"\n"); ,/;Aew;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1'kO{Ge*p:
lastExecuteTime=now; =C"[o\]VV
executeUpdate(); R+ * ; [
} pwFp<O"
else{ =Tj{)=^/#
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &,X}M
} mG~_*8}e<
} ?w3RqF@}
} =%Y1] F
//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 Ox3=1M0
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类写好了,下面是在JSP中如下调用。 K9!HW&?<|
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<% ]33!obM
CountBean cb=new CountBean(); 5{c;I<0
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); %xt9k9=vZ
CountCache.add(cb); aukcO;oG<
out.print(CountCache.list.size()+"<br>"); dkQ4D2W*\
CountControl c=new CountControl(); (jc@8@Wo.
c.run(); <2$vo
out.print(CountCache.list.size()+"<br>"); y Zafq"o
%>