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: WFks|D:sB
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CountBean.java a!{hC)d*
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/* Xa6qvg7/
* CountData.java t9n'!
* <sF!]R&4
* Created on 2007年1月1日, 下午4:44 lZ+/\s,]|
* _4S7wOq5
* To change this template, choose Tools | Options and locate the template under BC&^]M
* the Source Creation and Management node. Right-click the template and choose ix+x3OCip
* Open. You can then make changes to the template in the Source Editor. 33S`aJ
*/ @) ]t8(
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package com.tot.count; {.%0@{Y
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/** N}1-2
* .y(@Y6hO
* @author ^W{eO@
*/ Is~yVB02
public class CountBean { @~Rk^/0
private String countType; ?##y`.+O
int countId; J]_)gb'1BR
/** Creates a new instance of CountData */ K
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public CountBean() {} 0c{Gr 0[>
public void setCountType(String countTypes){ p@`4 Qz
this.countType=countTypes; Z 'Zd[."s
} !FO:^P
public void setCountId(int countIds){ (jt*u (C&Y
this.countId=countIds; O/'f$ Zj36
} Zr~"\llk
public String getCountType(){ aw;{<?*
return countType; ZW`HDrP`
} LIc*tsl
public int getCountId(){ e1Dj0s?i~K
return countId; ]oo|o1H87
} H==X0
} ook' u}h
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CountCache.java HXz iDnj
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/* il<gjlyR]L
* CountCache.java )E_!rR
* _p?I{1O
* Created on 2007年1月1日, 下午5:01 3<yCe%I:
* ggzAU6J
* To change this template, choose Tools | Options and locate the template under P'KY.TjWb
* the Source Creation and Management node. Right-click the template and choose vsxvHot=
* Open. You can then make changes to the template in the Source Editor. "1E?3PFJ
*/ Ni/|C19Z
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package com.tot.count; vQE` c@^{
import java.util.*; GWVEIZ
/** qsQ]M^@>
* F\I5fNs@
* @author $XtV8
*/ GXGN;,7EV
public class CountCache { kvY}
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public static LinkedList list=new LinkedList(); :ga 9Db9P
/** Creates a new instance of CountCache */ 9iiU,}M`j
public CountCache() {} w?*'vF_2:#
public static void add(CountBean cb){ 4"rb&$E
if(cb!=null){ 7 B4w.P,B
list.add(cb); %!1@aL]pQ
} ]M02>=1
} z0FR33-
} L2do2_
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CountControl.java Z%(Df3~gmm
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/* BIwgl@t!>
* CountThread.java lU>)n
* ci#Zvhtkr
* Created on 2007年1月1日, 下午4:57 i&?
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* q>wa#1X)
* To change this template, choose Tools | Options and locate the template under AqTR.}H
* the Source Creation and Management node. Right-click the template and choose `XFX`1
* Open. You can then make changes to the template in the Source Editor. =+kvL2nx-
*/ HQjxJd5P
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package com.tot.count; Y,p2eAss
import tot.db.DBUtils; exGhkt~
import java.sql.*; +sV# Z,
/** mCZF5r
* CYY
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* @author 7cJO)cm0'
*/ KR+ aY.
public class CountControl{ 4C2>0O<^s
private static long lastExecuteTime=0;//上次更新时间 @Wlwt+;fT
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 i:NJ>b
/** Creates a new instance of CountThread */ 1`7]C+Pv
public CountControl() {} IDL^0:eg<.
public synchronized void executeUpdate(){ y'i:%n}I
Connection conn=null; bF8xQ<i~Y
PreparedStatement ps=null; t(LlWd
try{ 6=aBD_2@
conn = DBUtils.getConnection(); mUe@Dud
conn.setAutoCommit(false); o%9Ua9|RR
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); k1@
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for(int i=0;i<CountCache.list.size();i++){ wjw<@A9
CountBean cb=(CountBean)CountCache.list.getFirst(); l=<F1L z
CountCache.list.removeFirst(); R
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ps.setInt(1, cb.getCountId()); v{\n^|=])
ps.executeUpdate();⑴ Es ZnGuY
//ps.addBatch();⑵ iLI.e rm
} 1GyA QHx,
//int [] counts = ps.executeBatch();⑶ K%.YNVHHC
conn.commit(); xOX*=Wv
}catch(Exception e){ (PE8H~d
e.printStackTrace(); d[qEP6B
} finally{ %s&E-*X
try{ vi()1LS/!
if(ps!=null) { e{#a{`?Uez
ps.clearParameters(); %^)Ja EUC
ps.close(); nOL 25 Y:
ps=null; fTi{oY,zTg
} 0YTtA]|`4
}catch(SQLException e){} -sGWSC
DBUtils.closeConnection(conn); {R6Zwjs
} HnYFE@Nl:U
} \M1M2(@pDJ
public long getLast(){ MSrY*)n!>O
return lastExecuteTime; GYy!`E
} e
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public void run(){ LbmB([p
long now = System.currentTimeMillis(); wb}N-8x
if ((now - lastExecuteTime) > executeSep) { 6vp8LNSW
//System.out.print("lastExecuteTime:"+lastExecuteTime); WP#_qqO
//System.out.print(" now:"+now+"\n"); ""U?#<}GD
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); MSm`4lw
lastExecuteTime=now; HK,G8:T
executeUpdate(); ]R3pBC"Jv
} v1tN
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else{ 6{,K7FL
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); }G:uzud10
} S<bz7
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} 1Ag ;s
} ofJ]`]~VG
//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 JQVw6*u{
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类写好了,下面是在JSP中如下调用。 Gh>fp
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<% "a%ASy>?g
CountBean cb=new CountBean(); M
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $'mB 8 S
CountCache.add(cb); Ubos#hP
out.print(CountCache.list.size()+"<br>"); Xxsnpb>
CountControl c=new CountControl(); #Ot*jb1
c.run(); R*TGn_J`
out.print(CountCache.list.size()+"<br>"); uJ!s%s2g
%>