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: (.%:Q0i1
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CountBean.java kc~Z1
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/* GsqrKrbJ
* CountData.java ttZ!P:H2
* Ik;~u8j1e
* Created on 2007年1月1日, 下午4:44 ,D
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* ,589/xTA@
* To change this template, choose Tools | Options and locate the template under z56W5g2
* the Source Creation and Management node. Right-click the template and choose =,gss&J!!
* Open. You can then make changes to the template in the Source Editor. _Mq@58q'
*/ .HZYSY:X
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package com.tot.count; 1K^/@^
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/** `9S<E
* vhWj_\m
* @author I+`~6
*/ /,E%)K;
public class CountBean { 6sQ"go$}
private String countType; 1mI)xDi9
int countId; w4(DR?[nC
/** Creates a new instance of CountData */ w`>xK
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public CountBean() {} ,@Ed)Zoh
public void setCountType(String countTypes){ )_xM)mH
this.countType=countTypes; qZ_^#%zO
} uO7Ti]H
public void setCountId(int countIds){ \vFkhm
this.countId=countIds; H[]j6D
} ]C)PZZI='
public String getCountType(){ ru'Xet
return countType; bB)EJCPq>
} g[H7.
public int getCountId(){ ;\Wg>sq
return countId; ]7dm`XV
} u@|GQXC
} m&2<?a}l
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CountCache.java $`l- cSH;
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/* tTWYlbDFN
* CountCache.java VEb}KFyP
* Z33wA?9
* Created on 2007年1月1日, 下午5:01 ?F?!QrL
* ua4QtDSs
* To change this template, choose Tools | Options and locate the template under Q
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* the Source Creation and Management node. Right-click the template and choose $G*$j!
* Open. You can then make changes to the template in the Source Editor. ##k=='dR
*/ J,{sRb%
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package com.tot.count; *QjFrw3
import java.util.*; )JuD !
/** (]mN09uE
* O^U{I?gQ
* @author wk8XD(&
*/ ~(I\O?k>H
public class CountCache { Bsz kQ>#6
public static LinkedList list=new LinkedList(); 9-bDgzk
/** Creates a new instance of CountCache */ #<v3G)|aS
public CountCache() {} *]x]U >EF
public static void add(CountBean cb){ Ae`K9
if(cb!=null){ s'} oVx]
list.add(cb); gtCd#t'(V
} `n5)oU2q
} !n)2HDYhx,
} "'6KQnpZ
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CountControl.java lD
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/* r%_)7Wk*
* CountThread.java T:na\y/{j
* f>p;Jh{2fn
* Created on 2007年1月1日, 下午4:57 -f Zm_FE
* s)ZL`S?</
* To change this template, choose Tools | Options and locate the template under mjB%"w!S
* the Source Creation and Management node. Right-click the template and choose WnUYZ_+e!
* Open. You can then make changes to the template in the Source Editor. i'`Z$3EF)
*/ ]'T-6
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package com.tot.count; o1I{^7/
import tot.db.DBUtils; BS+N
import java.sql.*; E >SnH
/** 3&3S*1b-H
* ?N $
* @author ~poy`h'
*/ Ov?k4kJ
public class CountControl{ mQJRq??P
private static long lastExecuteTime=0;//上次更新时间 a8Ci 7<V
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 oqUtW3y
/** Creates a new instance of CountThread */ +XFF@h&=t
public CountControl() {} uWi+F)GS^K
public synchronized void executeUpdate(){ :[\}Hn=
Connection conn=null; 7CM<"pV
PreparedStatement ps=null; Q> @0'y=s
try{ ivw2EEo,
conn = DBUtils.getConnection(); WBTX~%*U
conn.setAutoCommit(false); `sJkOEc`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?L{[84GSO
for(int i=0;i<CountCache.list.size();i++){ hQ8/-#LO_
CountBean cb=(CountBean)CountCache.list.getFirst(); f5d"H6%L
CountCache.list.removeFirst(); tR0o6s@v/<
ps.setInt(1, cb.getCountId()); k\x>kJ}0
ps.executeUpdate();⑴ `4 w0*;k;
//ps.addBatch();⑵ #/5jWH7U
} I^\YD9~=x
//int [] counts = ps.executeBatch();⑶ F!'b_gmz
conn.commit(); p~+)!Z#
}catch(Exception e){ p0'A\@|
e.printStackTrace(); vpOzF>O
} finally{ HPr5mWs:
try{ A*MlK"
if(ps!=null) { H.wp{m{
ps.clearParameters(); 2x3&o|J
ps.close(); p# O%<S@?
ps=null; H4^-M Sw
} X^fMt]
}catch(SQLException e){} }MXZ
DBUtils.closeConnection(conn); 9$UjZ$ v
} (K^9$w]tf
} NaB8cLURp
public long getLast(){ n1.]5c3p
return lastExecuteTime; ;se-IDN
} M/R#f9W
public void run(){ X#gZgz ='
long now = System.currentTimeMillis(); nmS3
if ((now - lastExecuteTime) > executeSep) { h"]v+u`!SM
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3D;\V&([
//System.out.print(" now:"+now+"\n"); ~A [ Ju%R
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }UQBaqDH
lastExecuteTime=now; [S-NGip
executeUpdate(); m3P%E8<Q#
} $&k zix
else{ I)Lg=n$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Aw9^}k}UfD
} jyLpe2 S
} r`B8Cik
} Vk@u|6U'
//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 rc9 \
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类写好了,下面是在JSP中如下调用。 /Q})%j1S0
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<% 4N*Fq!k~
CountBean cb=new CountBean(); l|U=(aA]h
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .5KRi6
CountCache.add(cb); "%-HZw%X
out.print(CountCache.list.size()+"<br>"); |giK]Z
CountControl c=new CountControl(); V:F)m!
c.run(); IWuR=I$t
out.print(CountCache.list.size()+"<br>"); VU}UK$JN
%>