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: tUksIUYD\
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CountBean.java \WqC^Di
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/* !'C8sNs
* CountData.java n5 <B*
* ]k$:sX
* Created on 2007年1月1日, 下午4:44 Sim$:5P
* d(j
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* To change this template, choose Tools | Options and locate the template under [{0/'+;9
* the Source Creation and Management node. Right-click the template and choose '=H3Y_{oO
* Open. You can then make changes to the template in the Source Editor. 8%`h:fE
*/ %J+ w9Z
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package com.tot.count; -k
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/** Qe0?n
* _H@8qR
* @author .NJ Ne
*/ cSBS38>
public class CountBean { B1j^qoC.5
private String countType; cm8co
int countId; g,G{%dGsk
/** Creates a new instance of CountData */ |2GrOM&S
public CountBean() {} iA|n\a~ny,
public void setCountType(String countTypes){ hh$i1n
this.countType=countTypes; 4}Y? :R
} ?Ld:HE
public void setCountId(int countIds){ >[N6_*K]
this.countId=countIds; _PLZ_c:O
} e< G[!m
public String getCountType(){ .zy2_3:
return countType; f[*g8p
} vl!o^_70(
public int getCountId(){ cR&d=+R&
return countId; ;Za^).=
} sHPlNwyy
} +f}w+
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CountCache.java "AlR%:]24~
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/* S#0C^
* CountCache.java cpH*!*S
* M=fhRCUB
* Created on 2007年1月1日, 下午5:01 Abpzf\F
* kaRjv
* To change this template, choose Tools | Options and locate the template under *c(J4
* the Source Creation and Management node. Right-click the template and choose s]HJcgI
* Open. You can then make changes to the template in the Source Editor. Gx|/
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*/ #4AqWyp#f
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package com.tot.count; ?btX&:j2P
import java.util.*; ti<;>P[4
/** AHT(Z~C
* b%X<'8z9Z
* @author #bb$Icmtk
*/ rW)}$|-Z
public class CountCache { PKev)M;C+
public static LinkedList list=new LinkedList(); k#2b3}(,
/** Creates a new instance of CountCache */ `uc`vkVZ
public CountCache() {} eH 9-GGr
public static void add(CountBean cb){ rc}=`D`
if(cb!=null){ rm<`H(cT
list.add(cb); qvs[Gkaa@
} >`n)-8
} :UfaMe5
} V.!z9AQ
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CountControl.java }]pO R&o
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/* "VeNc,-nfQ
* CountThread.java B~3qEdoK5`
* aSeh?2n8
* Created on 2007年1月1日, 下午4:57 HmV JkkksJ
* 1y7$"N8Xo
* To change this template, choose Tools | Options and locate the template under _Ry
* the Source Creation and Management node. Right-click the template and choose @iVEnb.'
* Open. You can then make changes to the template in the Source Editor. ZO \bCrk
*/ (DM8PtZg
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package com.tot.count; L @8[.
import tot.db.DBUtils; c-[IgX e
import java.sql.*; WWA!_
/** ?osYs<k \
* 'fIG$tr9X
* @author =/N0^
*/ =Q8$O
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public class CountControl{ YY$O"!."
private static long lastExecuteTime=0;//上次更新时间 hw&~OJeo
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 yiczRex%rq
/** Creates a new instance of CountThread */ Zk #C!]=
public CountControl() {} }
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public synchronized void executeUpdate(){ af/;D r@
Connection conn=null; ?nozB|*>ut
PreparedStatement ps=null; !_:|mu'
try{ +s5Yg,4*
conn = DBUtils.getConnection(); Z.0mX#
conn.setAutoCommit(false); 8=3$U+
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); -<5H8P-
for(int i=0;i<CountCache.list.size();i++){ d`KW]HJw
CountBean cb=(CountBean)CountCache.list.getFirst(); (XQl2C
CountCache.list.removeFirst(); %U$%x
ps.setInt(1, cb.getCountId()); PLWx'N-kqL
ps.executeUpdate();⑴ o&HFlDZ5jO
//ps.addBatch();⑵ T)cbpkH4
} WtbOm
//int [] counts = ps.executeBatch();⑶ SA6.g2pFz
conn.commit(); jhE3@c@pT
}catch(Exception e){ ,,(BW7(
e.printStackTrace(); O:X|/g0Y
} finally{ gd ; e-.
try{ }x:nhy`
if(ps!=null) { uX,ln(9I*H
ps.clearParameters(); @,TCg1@QJ
ps.close(); btB> -pT
ps=null; K9UWyM<(2C
} G;bE_O
}catch(SQLException e){} y7#vH<
DBUtils.closeConnection(conn); y &%2
} dRLvej,
} 0bG2YMs
public long getLast(){ PciiDh~/
return lastExecuteTime; ON$-g_s>)
} >l!DWi6
public void run(){ 2<+9lk
long now = System.currentTimeMillis(); 2a:JtJLl
if ((now - lastExecuteTime) > executeSep) { RkBbu4uQ-
//System.out.print("lastExecuteTime:"+lastExecuteTime); :WdiH)Zv
//System.out.print(" now:"+now+"\n"); W_G'wU3R
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); z,=k F I
lastExecuteTime=now; @c{b\is2
executeUpdate(); TWJ%? /d
} r1X\$&
else{ )WazbT@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sMAu*
} $Z^HI
} i^DZK&B@u
} FG5t\!dt<
//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 k-\RdX)E
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类写好了,下面是在JSP中如下调用。 tsu Mt
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<% 8_F 5c@7
CountBean cb=new CountBean(); KZSvT{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;-X5#
CountCache.add(cb); ln6Hr^@5
out.print(CountCache.list.size()+"<br>"); }e* OprF
CountControl c=new CountControl(); l>O~^41[
c.run(); r+%}XS%;h
out.print(CountCache.list.size()+"<br>"); X,8]g.<
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