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: +sNS
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CountBean.java I2}W /}
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/* w0QtGQ|
* CountData.java aRd~T6I
* ZvY"yl?e
* Created on 2007年1月1日, 下午4:44 eSPS3|YYn
* vrn4yHoZ
* To change this template, choose Tools | Options and locate the template under +in)(a.
* the Source Creation and Management node. Right-click the template and choose ?pL|eS7
* Open. You can then make changes to the template in the Source Editor. tX*@r
*/ B=Hd:P|
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package com.tot.count; o.s'0xP]
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/** AvL /gt:
* %$BRQ-O
* @author PW*Vfjf4
*/ " <bjS
public class CountBean { z:'m50'
private String countType; D@=]mh6vl
int countId; ~tUZQ5"
/** Creates a new instance of CountData */ #1YMpL
public CountBean() {} Km2~nkQ
public void setCountType(String countTypes){ =^"Sx??V
this.countType=countTypes; o:8ns m
} L3]J8oEmU
public void setCountId(int countIds){ ^&3vGu9
this.countId=countIds;
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} hV3]1E21"
public String getCountType(){ _/[qBe
return countType; s>9I#_4]
} e\)%<G5
public int getCountId(){ ^!['\
return countId; hB?#b`i^
} ? Fqh
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} TtJX(N~
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CountCache.java H UJqB0D
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/* a-5UG#o
* CountCache.java at>_EiS
* T*p7[}#
* Created on 2007年1月1日, 下午5:01 _ep&`K
* [[T7s(3
* To change this template, choose Tools | Options and locate the template under ueg%yvO
* the Source Creation and Management node. Right-click the template and choose \Y xG
* Open. You can then make changes to the template in the Source Editor. l@Lk+-[D
*/ ZllmaI
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package com.tot.count; HB9"T5Pd*
import java.util.*; &0 QUObK
/** gD$&OkH
* osc8;B/
* @author 8%4;'[UV
*/ x1=`Z@^
public class CountCache { `n+uA~
public static LinkedList list=new LinkedList(); !&%KJS6p4
/** Creates a new instance of CountCache */ pI@71~|R
public CountCache() {} l6zAMyau5
public static void add(CountBean cb){ EXdX%T\
if(cb!=null){ l4gH]!/@
list.add(cb); q\tr&@4iC
} /OKp(u;)z
} VnuG^)S
} %+r(*Q+0$f
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CountControl.java $`xpn#lz
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/* 1P]J3o
* CountThread.java n%r>W^2j
* 8] LF{Obz[
* Created on 2007年1月1日, 下午4:57 =K@LEZZ'/<
* W *0!Z:?
* To change this template, choose Tools | Options and locate the template under 2<7pe@c98
* the Source Creation and Management node. Right-click the template and choose HX.K{!5
* Open. You can then make changes to the template in the Source Editor. sta/i?n
*/ 'q}Ud10c
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package com.tot.count; #h ud_
import tot.db.DBUtils; h5{//0 y
import java.sql.*; -cUW,>E
/** OL1xxzo
* $%U}k=-
* @author M_O$]^I3w
*/ (,"%fc7<i
public class CountControl{ !,-'wT<v
private static long lastExecuteTime=0;//上次更新时间 `LH 9@Z{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 [\F:NLjiUy
/** Creates a new instance of CountThread */ X6sZwb
public CountControl() {} yO-2.2h
public synchronized void executeUpdate(){ !yg &zzP*
Connection conn=null; =$}`B{(H
PreparedStatement ps=null; Sw$&E
try{ 6oKlr,.
conn = DBUtils.getConnection(); -/3h&g
conn.setAutoCommit(false); ]V fp,"op
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); C&F%
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for(int i=0;i<CountCache.list.size();i++){ `?:{aOI
CountBean cb=(CountBean)CountCache.list.getFirst(); $_%
CountCache.list.removeFirst(); e?\Od}Hbw
ps.setInt(1, cb.getCountId()); r<]^.]3zj
ps.executeUpdate();⑴ zt((TD2
//ps.addBatch();⑵ daY0;,>
} &WCVdZK:
//int [] counts = ps.executeBatch();⑶ 7d{xXJ-
conn.commit(); 6
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}catch(Exception e){ wV-N\5!r%H
e.printStackTrace(); ;8F6a:\v
} finally{ b%VBSNZ
try{ zBrIhL]95
if(ps!=null) { E=v4|/['N
ps.clearParameters(); cLp9|y0r
ps.close(); YC{7;=Pf
ps=null; Z(E.F,k
} )W @
}catch(SQLException e){} %[,^2s
DBUtils.closeConnection(conn); oW7;t
} 4pDZ +}p
} p<VW;1bt5
public long getLast(){ yYC\a7Al4
return lastExecuteTime; r|jBKq~
} LGy!{c
public void run(){ e mq%"
;.
long now = System.currentTimeMillis(); 8BIPEY -I?
if ((now - lastExecuteTime) > executeSep) { Xp^>SSt:4
//System.out.print("lastExecuteTime:"+lastExecuteTime); B]D51R\}VE
//System.out.print(" now:"+now+"\n"); >03JQe_#*L
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [xs`Pi
lastExecuteTime=now; ~O~we
executeUpdate(); m[5ed1+
} lKirc2
else{ a
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]sI{+$~:c
} |qk%UN<
} kr
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} D@mqfi(x
//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 :)e/(I]
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类写好了,下面是在JSP中如下调用。 I>3G"[t
RML'C:1
<% Zfr?(y+3
CountBean cb=new CountBean(); *
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); J0Y-e39 `
CountCache.add(cb); qr/N ?,
out.print(CountCache.list.size()+"<br>"); I'cM\^/h
CountControl c=new CountControl(); DB1Y`l
c.run(); dZbG#4oO
out.print(CountCache.list.size()+"<br>"); )3_g&&
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