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: BwwOaO@L
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CountBean.java fB+4mEG@
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/* x5_V5A/@LU
* CountData.java #?8dInu>
* _]btsv\)f
* Created on 2007年1月1日, 下午4:44 `,|"rn#S
* [%'yHb~<
* To change this template, choose Tools | Options and locate the template under {/SUfXq
* the Source Creation and Management node. Right-click the template and choose 5[3vup?
* Open. You can then make changes to the template in the Source Editor. aI]EwVz-q
*/
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package com.tot.count; x"q!=&>f
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/** ^$-ID6
* `6a
* @author 3oX\q/$
*/ T.\=R
public class CountBean { ;oW#>!HrY
private String countType; *@`Sx'5!
int countId; Fd!Np7xw
/** Creates a new instance of CountData */ D4nYyj1O3
public CountBean() {} qKu/~0a/
public void setCountType(String countTypes){ JB.f7-
this.countType=countTypes; M?m Pi 3
} M4[(.8iE
public void setCountId(int countIds){ .d{@`^dh1]
this.countId=countIds; yf3c-p
} <4r3ZV;'
public String getCountType(){ E(]39B"i
return countType; }pqnF53
} F(+,M~
public int getCountId(){ g{{DC )>
return countId; z2'3P{#s
} aQzDOeTi
} ,gAa9
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CountCache.java LsB|}_j7
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/* WUnz
* CountCache.java e$'|EE.=q+
* |6@s6]%X}
* Created on 2007年1月1日, 下午5:01 g
i>`
* h`Ld%iN\
* To change this template, choose Tools | Options and locate the template under d)hA'k
* the Source Creation and Management node. Right-click the template and choose BMaw]D
* Open. You can then make changes to the template in the Source Editor. Eod'Esye5
*/ *Ae>
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package com.tot.count; t!^ j0 q
import java.util.*; S9\_ODv
/** :(7icHa
* (%p@G5GU
* @author f_\,H|zco)
*/ yhTC?sf<
public class CountCache { t5t!-w\M$+
public static LinkedList list=new LinkedList(); g~ubivl2
/** Creates a new instance of CountCache */ T$w`=7
public CountCache() {} ))M!"*
public static void add(CountBean cb){ \N3A2L)l
if(cb!=null){ \PU7,*2
list.add(cb); Q`= ,&;T>
} k5M3g*
} :c03"jvYE
} (rTn6[*
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CountControl.java ,u.G6"<
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/* &Ul8h,qw
* CountThread.java o/dj1a~U
*
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* Created on 2007年1月1日, 下午4:57 faTp|T`nY
* t[=-4;
* To change this template, choose Tools | Options and locate the template under ^&[Z@*A8#
* the Source Creation and Management node. Right-click the template and choose dMw7UJ
* Open. You can then make changes to the template in the Source Editor. Ec2?'*s
*/ :X+!W_xR
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package com.tot.count; #/"?.Z;SSH
import tot.db.DBUtils; )h0
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import java.sql.*; B7QuSo//
/** $0[t<4K`yn
* #{f%b,.yxt
* @author bX*>Zm
*/ Kg8n3pLAX
public class CountControl{ d@b" ~r}
private static long lastExecuteTime=0;//上次更新时间 CpGy'Ia
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 "@s</HGo
/** Creates a new instance of CountThread */ :<QmG3F
public CountControl() {} a8w/#!^34
public synchronized void executeUpdate(){ "A9qC*6[
Connection conn=null; Pl/}`H:R&
PreparedStatement ps=null; q0sdL86
try{ >U7{EfUJdx
conn = DBUtils.getConnection(); 2=]Xe#5J=
conn.setAutoCommit(false); =PM6:3aKh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); _GW, 9s^A
for(int i=0;i<CountCache.list.size();i++){ 'lWgHmE
CountBean cb=(CountBean)CountCache.list.getFirst(); #ULjK*)R
CountCache.list.removeFirst(); BmhIKXE{*
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ V'M#."Of/
//ps.addBatch();⑵ *!5X!\e_
} B'}pZOa[Wb
//int [] counts = ps.executeBatch();⑶ xq@_'
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conn.commit(); `zoC++hx
}catch(Exception e){ oVAY}q|wU
e.printStackTrace(); :iEIo7B
} finally{ R!z32 <5k
try{ `fM]3]x>
if(ps!=null) { E7`Q=4@e
ps.clearParameters(); KAI/*G\z
ps.close(); @h
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ps=null; Ge_Gx*R
} [sc4ULS &
}catch(SQLException e){} {kOTQG?y
DBUtils.closeConnection(conn); *]K/8MbiF
} o=)["V
} <FofRFaS
public long getLast(){ uXuA4o$t-
return lastExecuteTime; N~!
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} sZh| <2
public void run(){ NK!#K>AO
long now = System.currentTimeMillis(); cOoF +hz0O
if ((now - lastExecuteTime) > executeSep) { k [eWhdSw
//System.out.print("lastExecuteTime:"+lastExecuteTime); >c30kpGg
//System.out.print(" now:"+now+"\n"); pPH"6
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); '7yVvd
lastExecuteTime=now; x%J.$o[<_
executeUpdate(); [}Z!hq
} jccSjGX@w
else{ "lnI@t{o
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]w/%>
} P. Gmj;
} g;-6Hg'
} w:3CWF4q]
//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 OhW o
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类写好了,下面是在JSP中如下调用。 *-,jIaL;
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<% 2qDyb]9
CountBean cb=new CountBean(); bH`r=@.:cu
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Q&`if
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CountCache.add(cb); Vg^,Ky,
out.print(CountCache.list.size()+"<br>"); 1zGhX]z
CountControl c=new CountControl(); m#|h22^H
c.run(); /VHQ!Wi
out.print(CountCache.list.size()+"<br>"); 4NDT5sL
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