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: Zqi;by%
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CountBean.java I_.Jo `lK~
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/* w^EUBRI-
* CountData.java ta
* b^s>yN
* Created on 2007年1月1日, 下午4:44 tNbL)
* [}*xxy
* To change this template, choose Tools | Options and locate the template under 0?80V'
* the Source Creation and Management node. Right-click the template and choose ;NoD4*
* Open. You can then make changes to the template in the Source Editor. fkHCfcU
*/ >Hd Pcsl L
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package com.tot.count; sUe<21:
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/** Jf</83RZ
* j&y>?Y&Sb
* @author wJ>.I<F6B
*/ 7g%.:H=
public class CountBean { ^U;r>[T9h
private String countType; f53WDI6
int countId; eVvDis
/** Creates a new instance of CountData */ ZHN}:W/p
public CountBean() {} -~+Y0\%E
public void setCountType(String countTypes){ a +lTAe
this.countType=countTypes; M/x*d4b_
} QnMN8Q9
public void setCountId(int countIds){ ^MczumG[
this.countId=countIds; 9zKbzT]
} =5kTzH.
public String getCountType(){ sry`EkS
return countType; Om,M8!E
} 5^0K5R6GQf
public int getCountId(){ * .P3fVlZ
return countId; (X|`|Y
} \L]T|]}(
} gPf^dGi7t
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CountCache.java Su>UXuNdE#
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/* "raC?H
* CountCache.java au?5^u\
* U/j+\Kc~
* Created on 2007年1月1日, 下午5:01 dk@j!-q^
* .!2Ac
* To change this template, choose Tools | Options and locate the template under \0bZ1"
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. ) mG
*/ Xxmvg.Nl
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package com.tot.count; nNP{>\x;"
import java.util.*; k<.VR"I
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/** <&87aDYz
* r$/.x6g//
* @author R1j)0b6cQ%
*/ K[Ao_v2g
public class CountCache { =>u9k:('9
public static LinkedList list=new LinkedList(); ];7/DM#Np
/** Creates a new instance of CountCache */ X)^&5;\`
public CountCache() {} \CK f/:"
public static void add(CountBean cb){ MU#$tXmnC
if(cb!=null){ \+I+Lrj%
list.add(cb); &h67LMD!
} $8t\|O3
} Q%Y rm
} PTf.(B"z
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CountControl.java .#wU+t>
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/* se^(1R k
* CountThread.java *p>1s!i
* m
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* Created on 2007年1月1日, 下午4:57 :978D0}{p
* ANWUo}j
* To change this template, choose Tools | Options and locate the template under "PtOe[Xk
* the Source Creation and Management node. Right-click the template and choose 9xZ?}S:d
* Open. You can then make changes to the template in the Source Editor. @K}8zMmW#
*/ h"849c;C.
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package com.tot.count; o<f|jGY0
import tot.db.DBUtils; otSF8[
import java.sql.*; {S=gXIh(y
/** $0wF4$)
* h 1`yW#%
* @author t1%<l
*/ GTBT0$9g.
public class CountControl{ _>)=c<HL
private static long lastExecuteTime=0;//上次更新时间 z ;KUIWg
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 v:w $l{7
/** Creates a new instance of CountThread */ ;DN:AgXP
public CountControl() {} OK1f Y`$z
public synchronized void executeUpdate(){ n?z^"vv$i
Connection conn=null; AfOq?V
PreparedStatement ps=null; u*C"d1v=
try{ C~([aH@-I
conn = DBUtils.getConnection(); ab-MEN`5
conn.setAutoCommit(false); sXmo.{Ayb
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); |=U(8t
for(int i=0;i<CountCache.list.size();i++){ /@~&zx&_
CountBean cb=(CountBean)CountCache.list.getFirst(); y+D"LeCAad
CountCache.list.removeFirst(); 3V2w1CERE
ps.setInt(1, cb.getCountId()); PdNxuy
ps.executeUpdate();⑴ $v*0\O
//ps.addBatch();⑵ YTo^Q&
} 5q>u]n9]
//int [] counts = ps.executeBatch();⑶ Zd]2>h
conn.commit(); |Je+y;P7
}catch(Exception e){ M_monj}Z
e.printStackTrace(); eOI#T'5
} finally{ J&jNONu?
try{ my(yN|
if(ps!=null) { $h|rd+},
ps.clearParameters(); 8G0DuMI5
ps.close(); TR([u
ps=null; D8I)3cXa'
} lS:R##
}catch(SQLException e){} B>TI dQ
DBUtils.closeConnection(conn); qf
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} Y
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} afWEt -
public long getLast(){ .1 =8c\%
return lastExecuteTime;
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} 7Yjxx+X9
public void run(){ dPfDPb
long now = System.currentTimeMillis(); _-.~>C
if ((now - lastExecuteTime) > executeSep) { _Mis-K:]{?
//System.out.print("lastExecuteTime:"+lastExecuteTime); #:?MtVC
//System.out.print(" now:"+now+"\n"); $3C$])k
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); UIl^s8/
lastExecuteTime=now; F< #!83*%
executeUpdate(); mp x/~`c
} Q(e 3-a
else{ 0Q_@2
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); al3[Ph5G
} nPj/C7j
} LpJ_HU7@lk
} 2r]!$ hto
//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 rLm:qu(F1
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类写好了,下面是在JSP中如下调用。 c*"TmDY
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