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: 6x+ujUBkK
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CountBean.java 7- B.<$uC
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/* A2_ut6&eb
* CountData.java om3
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* <_EKCk
* Created on 2007年1月1日, 下午4:44 peQwH
* B}e/MlX3M
* To change this template, choose Tools | Options and locate the template under a)_3r]sv^
* the Source Creation and Management node. Right-click the template and choose m4:c$5
* Open. You can then make changes to the template in the Source Editor. L*@`i ]jl
*/ mypV[
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package com.tot.count; Ayz*2N`%
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/** (jc@8@Wo.
* ^Hd[+vAvR
* @author ]a $6QS
*/ vygzL U^
public class CountBean { ' \JE>#
private String countType; ]#tB[G
int countId; !3Q0Ahf
/** Creates a new instance of CountData */ ~#_~DqbMZ5
public CountBean() {} :@A&HkF
public void setCountType(String countTypes){ b--=GY))F
this.countType=countTypes; F%OP,>zl
} z7K{ ,y
public void setCountId(int countIds){ Q$%apL
this.countId=countIds; (q)}`1d'
} 7]=&Q4e4
public String getCountType(){ z.vQ1~s
return countType; 6h 0qtXn-
} _`$Q6!Z)l
public int getCountId(){ A*JOp8\)
return countId; 4TtC~#D:
} 3I)~;>meo
} (gt\R}
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CountCache.java Q(|@&83].
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/* yD\q4G
* CountCache.java VB |?S|<
* %hB-$nE
* Created on 2007年1月1日, 下午5:01 *x36;6~W;
* -amo8V;2H
* To change this template, choose Tools | Options and locate the template under ^y<^hKjV
* the Source Creation and Management node. Right-click the template and choose ,d"T2Hy
* Open. You can then make changes to the template in the Source Editor. &<&tdShI
*/ m+QS -woHn
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package com.tot.count; Z@~gN5@,M
import java.util.*; YteIp'T
/** r,5e/X
* Mz@{_*2
* @author iZGbNN
*/ Lg:1zC
public class CountCache { Wu>]R'C
public static LinkedList list=new LinkedList(); @0 +\:F
/** Creates a new instance of CountCache */ P1#g{f
public CountCache() {} LdUz;sb
public static void add(CountBean cb){ [2:d@=%.
if(cb!=null){ ZO+RE7f*?c
list.add(cb); l*CulVX
} g2OnLEF]s
} ,@*5x'auK
} rH}|~
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CountControl.java Nr|Gw
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/* UZdnsG7
* CountThread.java FFT)m^4p.
* x39tnf/F
* Created on 2007年1月1日, 下午4:57 ;
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* *5'8jC"2g
* To change this template, choose Tools | Options and locate the template under YPK@BmAdE
* the Source Creation and Management node. Right-click the template and choose o&JoeKXor
* Open. You can then make changes to the template in the Source Editor. ,!=
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*/ <ZC.9
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package com.tot.count; ?QP>rm
import tot.db.DBUtils; &4Z8df!
import java.sql.*; >d 5-if
/** Hav &vV
* E|=x+M1sH
* @author gS(3 m_
*/ >+O0W)g{o
public class CountControl{ 6IqPZ{g9K'
private static long lastExecuteTime=0;//上次更新时间 u`ir(JIj]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8mX!mYO3c
/** Creates a new instance of CountThread */ +3,7 Apj
public CountControl() {} KOixFn1
public synchronized void executeUpdate(){ /xn|d#4
Connection conn=null; 2> a&m>
PreparedStatement ps=null; @ &jR^`Y.
try{ \kE0h\
conn = DBUtils.getConnection(); fTxd8an{
conn.setAutoCommit(false); <IrhR,@M,L
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Q%CrB>|@
for(int i=0;i<CountCache.list.size();i++){ ^B"LT>.[
CountBean cb=(CountBean)CountCache.list.getFirst(); }T_"Vg q
CountCache.list.removeFirst(); xQR/Xp!h
ps.setInt(1, cb.getCountId()); v.ZUYa|
ps.executeUpdate();⑴ It*U"4lgi
//ps.addBatch();⑵ L15)+^4n
} s}zR@ !`
//int [] counts = ps.executeBatch();⑶ &r,vD,
conn.commit(); EU(e5vO
}catch(Exception e){ C(>!?-.
e.printStackTrace(); ,[n9DPZ
} finally{ 7mtx^
try{ *r.%/^@
if(ps!=null) { >s<Bu' r
ps.clearParameters(); Wvb ~j
ps.close(); /&6{}n
ps=null; 6;E3|st1X
} ,Uh^e]pC
}catch(SQLException e){} +9/K|SB{$
DBUtils.closeConnection(conn); "8Dm7)nB
} `;mgJD
} m%9Yo%l~
public long getLast(){ J;sQvPHV8
return lastExecuteTime; R3g)LnN
} >VhZv75
public void run(){ @tT`s^e
long now = System.currentTimeMillis(); ru:"c^W:[
if ((now - lastExecuteTime) > executeSep) { G[}v?RLI
//System.out.print("lastExecuteTime:"+lastExecuteTime); u<j;+-]8h
//System.out.print(" now:"+now+"\n"); 8P]nO+
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^*jwe^
lastExecuteTime=now; .1(_7!m@
executeUpdate(); `yR/M"u6T
} bAlty}U
else{ \7\sx:!$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &n*ga$Q
} 6TRLHL~B
} fAh|43Y*a
} p$"~vA .
//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 !S~)U{SSK
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类写好了,下面是在JSP中如下调用。 Q 1i5"'][
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<% cO:lpsKYQ
CountBean cb=new CountBean(); ;9~YQW@|
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0L;,\&*u
CountCache.add(cb); *mV?_4!,f7
out.print(CountCache.list.size()+"<br>"); [__P-h{J
CountControl c=new CountControl(); >QDyG8*
c.run(); IFW(nB(
out.print(CountCache.list.size()+"<br>"); r@JMf)a]
%>