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: bv}e[yH
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CountBean.java NJg )S2]7
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/* T _fM\jdI
* CountData.java \%&eDE 0
* @DSKa`
* Created on 2007年1月1日, 下午4:44 ;KT5qiqYH
* `pqTiV
* To change this template, choose Tools | Options and locate the template under 5 &0qr$
* the Source Creation and Management node. Right-click the template and choose VPb8dv(a3
* Open. You can then make changes to the template in the Source Editor. $4BvDZDk`B
*/ H^M>(kT#&
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package com.tot.count; 8k;il54#
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/** ]AX3ov6z9;
* |^"0bu"
* @author <T]ey
*/ e(Rbq8D
public class CountBean { U_WO<uhC
private String countType; Gr#WD=I-}
int countId; I:("f+
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/** Creates a new instance of CountData */ .AZwVP<
public CountBean() {} iU AY
public void setCountType(String countTypes){ I{=Yuc
this.countType=countTypes; ri6KD
} [pInF
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public void setCountId(int countIds){ w/*m_O\!
this.countId=countIds; 9dWz3b1[]
} t(jE9t|2e6
public String getCountType(){ >F s/Wet
return countType; 5{Q9n{dOh
} 5~j#Z (}u
public int getCountId(){ x0WinLQ
return countId; ZvMU3])u
} N$x&k$w R
} kDI?v6y5
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CountCache.java t"Ah]sD
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/* hzRKv6
* CountCache.java dDIR~!T
* W"GW[~
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* Created on 2007年1月1日, 下午5:01 |<5F08]v
* _TGs .t
* To change this template, choose Tools | Options and locate the template under =*"8N-FU
* the Source Creation and Management node. Right-click the template and choose zRou~Kxi
* Open. You can then make changes to the template in the Source Editor. *tgu@9b
*/ y^ |u'XK
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package com.tot.count; X-(4/T+v
import java.util.*; J=t}9.H~=
/** -Ep#q&\
* 0%dOi
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* @author tH44\~
*/ }\Rmwm-
public class CountCache { fBj)HoHQW
public static LinkedList list=new LinkedList(); %9a3$OGZX
/** Creates a new instance of CountCache */ t>/x-{bH\
public CountCache() {} d?T!)w
public static void add(CountBean cb){ -v.\W y~\
if(cb!=null){ W(R~K -
list.add(cb); ^9:`D@Z+
} .<F46?HS
} bXOKC
} yV )fJ_
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CountControl.java PPr Pj^%z=
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/* [I3Nu8
* CountThread.java CV.|~K0O
* ]JYE#F
* Created on 2007年1月1日, 下午4:57 2&>t,;v@
* &hI!mo
* To change this template, choose Tools | Options and locate the template under _ERtL5^
* the Source Creation and Management node. Right-click the template and choose A5TSbW']+5
* Open. You can then make changes to the template in the Source Editor. [
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*/ K F_fz
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package com.tot.count; i7XY3yhC
import tot.db.DBUtils; hm! J@
import java.sql.*; A}(]J!rc
/** Ee2P]4_d
* !6%?VJB|b
* @author B[GC@]HE
*/ ~p?ArZb
public class CountControl{ -&>V.hi7
private static long lastExecuteTime=0;//上次更新时间 ['=O>YY
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AAlc %d/9
/** Creates a new instance of CountThread */ {MUiK5:
public CountControl() {} oxlor,lw/
public synchronized void executeUpdate(){ $qQYxx@
Connection conn=null; ;rT'~?q
PreparedStatement ps=null; ly17FLJ].
try{ $lJcC |*
conn = DBUtils.getConnection(); !Ud'(iGa
conn.setAutoCommit(false); ?f"5yQ-B
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); |NZi2Bu
for(int i=0;i<CountCache.list.size();i++){ G|rE\h 2w
CountBean cb=(CountBean)CountCache.list.getFirst(); >0{}tRm-P&
CountCache.list.removeFirst(); Q:(mK* _
ps.setInt(1, cb.getCountId()); n?EgC8b9
ps.executeUpdate();⑴ 3y}E*QE
//ps.addBatch();⑵ !Zj]0,^
} .P)lQk\
//int [] counts = ps.executeBatch();⑶ = UH3.
conn.commit(); %;k Hnl
}catch(Exception e){ "=Br&FN{|
e.printStackTrace(); 4f[%Bb
} finally{ ~V8z%s@
try{ u[b |QR=5
if(ps!=null) { f$xXR$mjf
ps.clearParameters(); ,IjZQ53q~
ps.close(); $ZBYOA
ps=null; VV$t*9w
} )R JEOl1
}catch(SQLException e){} {|?^@
DBUtils.closeConnection(conn); %lHHTZ{+
} Y~I<L ocv
} JI5o~;}m
public long getLast(){ @Dh2@2`>
return lastExecuteTime; QhZg{v[d
} 5daq}hsQs
public void run(){ 8z#Qp(he
long now = System.currentTimeMillis(); p\w<~pN[
if ((now - lastExecuteTime) > executeSep) { m\`>N_4*9
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7Z< ~{eD,
//System.out.print(" now:"+now+"\n"); 'o-4'
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]3_b3@k
lastExecuteTime=now; a `R%\@1
executeUpdate(); @sXv5kZ:
} dkC[SG`
else{ 3v8LzS3@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); gg/`{
} {~U3|_"[pX
} |THpkfW
} |\,OlX,
//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 #CC5+
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类写好了,下面是在JSP中如下调用。 q)k:pQ
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<% 'C[tPP
CountBean cb=new CountBean(); FnO@\{M"A
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 'FErk~}/4s
CountCache.add(cb); y}?|+/ dN
out.print(CountCache.list.size()+"<br>"); ORExI.<`W
CountControl c=new CountControl(); ;k <dp7^
c.run(); cM#rus?)+
out.print(CountCache.list.size()+"<br>"); [4z,hob
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