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: ]')y(_{
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CountBean.java 'p78^4'PL
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/* O jNOvh&N
* CountData.java NEPK
* R4T@ ]l&W
* Created on 2007年1月1日, 下午4:44 +FAxqCkA
* 8B]\;m
* To change this template, choose Tools | Options and locate the template under 2(x|
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* the Source Creation and Management node. Right-click the template and choose rA^=;?7Q
* Open. You can then make changes to the template in the Source Editor. ZJ~0o2xZ'
*/ 6 !?]
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package com.tot.count; 8aC=k@YE
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/** kM[!UOnC!<
* / 9,'.
* @author %Ofw"W
*/ 7&/1K%x9;
public class CountBean { 'rS\9T
private String countType; B2* 7H
int countId; XA(.O|VZ
/** Creates a new instance of CountData */ wnK6jMjkSf
public CountBean() {} /d">}%Jn
public void setCountType(String countTypes){ ;MK|l,aIQ
this.countType=countTypes; /hmDePo}
} 9W+DW_M
public void setCountId(int countIds){ $}0!dR2
this.countId=countIds; ==gL!e{
} $E[M[1j
public String getCountType(){ `IJ)'$pn
return countType; tw=A]
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} Oo-4WqRJ
public int getCountId(){ k3e6y
return countId; ssS"X@VZ
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} LFqY2,#i
} B0Ay
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CountCache.java ,3iD/8_
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/* N 3O!8A_
* CountCache.java +'iqGg-
* dZ8ldpf8
* Created on 2007年1月1日, 下午5:01 K7.ayM 0
* 2hso6Oy/v{
* To change this template, choose Tools | Options and locate the template under PFx.uqp
* the Source Creation and Management node. Right-click the template and choose I$x<B7U
* Open. You can then make changes to the template in the Source Editor. ;K|K]c
*/ ;($xAAR
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package com.tot.count; #G?#ot2o
import java.util.*; F(Zf=$cx
/** Q9h=1G\K
* RRYcg{g
* @author :f%kkatO
*/ ,UC|[-J
public class CountCache { ePl+ M
public static LinkedList list=new LinkedList(); 7lAJ
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/** Creates a new instance of CountCache */
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public CountCache() {} RJd*(!y
public static void add(CountBean cb){ 0H.bRk/P+
if(cb!=null){ &iq'V*+-\
list.add(cb); 0-aaLC~Z>
} $Q}L*4?]
} Z%LS{o~LK.
} u rQvJ
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CountControl.java jk_yrbLc
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/* {~R?f$}""j
* CountThread.java uHbbPtk
* Wd(|w8J{a
* Created on 2007年1月1日, 下午4:57 'rFLG+W
* ]]`[tVaFr
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose ;14Q@yrZ0
* Open. You can then make changes to the template in the Source Editor. nRw.82eK.
*/ :RZ'_5P[If
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package com.tot.count; B-L@ 0gH
import tot.db.DBUtils;
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import java.sql.*; zL50|U0H
/** K.&6c,P]
* r3OtQ
* @author '43U v
*/ ,1!Y!,xy
public class CountControl{ v;g,qO!LJ
private static long lastExecuteTime=0;//上次更新时间 8@rF~^-_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `:m=rT_
/** Creates a new instance of CountThread */ %iYro8g!,
public CountControl() {} n>:e8KVM;
public synchronized void executeUpdate(){ k%-UW%
Connection conn=null; N!v>2"x8q
PreparedStatement ps=null; $ntC{a>&
try{ e$Y7V
conn = DBUtils.getConnection(); x
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conn.setAutoCommit(false); 0|0IIgy
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Dk")/ ib
for(int i=0;i<CountCache.list.size();i++){ $gk=~p|
CountBean cb=(CountBean)CountCache.list.getFirst(); "
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CountCache.list.removeFirst(); ntL%&wY
ps.setInt(1, cb.getCountId()); ww%4MHPp8
ps.executeUpdate();⑴ 4
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//ps.addBatch();⑵ ,g|ht%"
} ]^a{?2ei
//int [] counts = ps.executeBatch();⑶ $SniQ
conn.commit(); eSMno_Gt3
}catch(Exception e){ o@} qPvt0
e.printStackTrace();
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} finally{ cj[%.M5iBA
try{ RzLeR%O
if(ps!=null) { Q2@yUDd!
ps.clearParameters(); iq8Hq)I]
ps.close(); pf=CP%L
ps=null; !+Sd%2o
} S|IDFDn
}catch(SQLException e){} W%9"E??c
DBUtils.closeConnection(conn); (Fk&~/SP
} 3+M+5
} J+hifO
public long getLast(){ lgHzI(
return lastExecuteTime; mT1Q7ta*P
} 'w\Gd7E
public void run(){ pSpxd|k
long now = System.currentTimeMillis(); +gb"}
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if ((now - lastExecuteTime) > executeSep) { gkx<<)y
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//System.out.print("lastExecuteTime:"+lastExecuteTime); `M_w^&6+n
//System.out.print(" now:"+now+"\n"); 2QIo|$
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); oR<;Tr~{q
lastExecuteTime=now; 7{f{SIB
executeUpdate(); ;,u7)
} mi sPJO&QD
else{ KVpQ,x&q~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Xkp`1UTH
} piPV&ytI
} x^UAtKSy
} n(Ry~Xu_
//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 Vjr}"K$Y
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类写好了,下面是在JSP中如下调用。 AiV1
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<% >vQKCc|93
CountBean cb=new CountBean(); Xm.["&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <d3N2
CountCache.add(cb); LBhDP5qF
out.print(CountCache.list.size()+"<br>"); RsP^T:M}$
CountControl c=new CountControl(); ,#80`&\%
c.run(); \MmKz^tO
out.print(CountCache.list.size()+"<br>"); 0J9Ub
%>