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: qIy9{LF
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CountBean.java W"~"R
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/* pXNH
* CountData.java ZTGsZ}{5
* N>j*{]OY+{
* Created on 2007年1月1日, 下午4:44 <qoPBm])
* c!$~_?]
* To change this template, choose Tools | Options and locate the template under 1JGww]JZo
* the Source Creation and Management node. Right-click the template and choose lP(<4mdP
* Open. You can then make changes to the template in the Source Editor. M;z )c|Z
*/ .D=#HEshk
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package com.tot.count; v9D[|4
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/** 'F1<m^
* Hc0V4NHCaL
* @author x;7p75Wm
*/ <Lle1=qQ
public class CountBean { @a]`C
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private String countType; "+&@iL
int countId; _=qk.| p/
/** Creates a new instance of CountData */ nzB!0U
public CountBean() {} ]#rmk!VT?
public void setCountType(String countTypes){ ZI!;~q
this.countType=countTypes; MLmk=&d
} Y=UN`vRR
public void setCountId(int countIds){ h9%.tGx
this.countId=countIds; 1(VskFtZF
} z)&&Ym#
public String getCountType(){ ]V"B`ip[2
return countType; U`4t4CHA
} Bo*Wm
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public int getCountId(){ *u34~v16,
return countId; 4Gh%PUV#
} !NhVPb,
} @jr$4pM?
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CountCache.java (bogAi3<F
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/* ;Ac!"_N?7
* CountCache.java zL+M-2hV
* yA<\?Ps
* Created on 2007年1月1日, 下午5:01 I]~UOl
* i:^
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* To change this template, choose Tools | Options and locate the template under *pGbcBQ
* the Source Creation and Management node. Right-click the template and choose y(r(q
* Open. You can then make changes to the template in the Source Editor. ~HX'8\5
*/ aFy'6c}
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package com.tot.count; ZN`I4Ak
import java.util.*; 04E#d.o'
/** e0o)Jo.P
* O FlY"OS[
* @author
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*/ 2CPh'7|l
public class CountCache { _4t
public static LinkedList list=new LinkedList(); k'd=|U;(FV
/** Creates a new instance of CountCache */ T!H }^v
public CountCache() {} 4V5h1/JPm
public static void add(CountBean cb){ Nu%MXu+
if(cb!=null){ sTYA
list.add(cb); <(o) * Zmo
} z`y^o*qc]
} yLvU@V@~
} Z1+1>|-iW
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CountControl.java vQ
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/* lLL) S
* CountThread.java yKOC1( ~
* j1$s^ -9
* Created on 2007年1月1日, 下午4:57 wb-_CQ
* Cy\! H&0wg
* To change this template, choose Tools | Options and locate the template under &o)eRcwH`
* the Source Creation and Management node. Right-click the template and choose WS ^%<
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* Open. You can then make changes to the template in the Source Editor.
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*/ EYKV}`
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package com.tot.count; K!SFS
import tot.db.DBUtils; y$HV;%G{26
import java.sql.*; O>2i)M-h9x
/** yUFT9bD
* ,S=ur%
* @author Md1ePp]
*/ oei2$uu
public class CountControl{ #;>v,Jo
private static long lastExecuteTime=0;//上次更新时间 ]KRw[}z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 2xpI|+a%
/** Creates a new instance of CountThread */ /.[78:G\,
public CountControl() {} n ]P,5
public synchronized void executeUpdate(){ ;[[oZ
Connection conn=null; e[L%M:e9U
PreparedStatement ps=null; IM~2=+
try{ [Xo[J?w],2
conn = DBUtils.getConnection(); eq$.np
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); &\M<>>IB
for(int i=0;i<CountCache.list.size();i++){ QetyuhS~
CountBean cb=(CountBean)CountCache.list.getFirst(); _{YUWV50}
CountCache.list.removeFirst(); Vqxxm&^P
ps.setInt(1, cb.getCountId()); GUqBnRA8j
ps.executeUpdate();⑴ @L5s.]vg=
//ps.addBatch();⑵ V82N8-l
} h2m@Q={
//int [] counts = ps.executeBatch();⑶ xIa8Ac
conn.commit(); Z(a,$__
}catch(Exception e){ 3g5
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e.printStackTrace(); /X97dF)zt
} finally{ 59M\uVWR
try{ a}/ A]mu
if(ps!=null) { 8{4jlL;"`?
ps.clearParameters(); }:hN}*H
ps.close(); /}$D&KwYg
ps=null; 7y'2
} p`06%"#
}catch(SQLException e){} h_K!ch}
DBUtils.closeConnection(conn); JWvL
} c^EU&q{4
} F>s5<pKAX
public long getLast(){ xg_9#
return lastExecuteTime; ,LVZ
} 9._owKj
public void run(){ J'Y;j^
long now = System.currentTimeMillis(); !juh}q&}|
if ((now - lastExecuteTime) > executeSep) { ) i=.x+Q
//System.out.print("lastExecuteTime:"+lastExecuteTime); f#b;s<G
//System.out.print(" now:"+now+"\n"); ])NQzgS
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); aLt2fB1 )
lastExecuteTime=now; 4
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executeUpdate(); MI\35~JAN
} {#4F}@Q
else{ fy|$A@f
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); vKmV<*K
} %oHK=],|1
} .h[yw$z6
} LF\HmKM,
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 bOS; 1~~
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类写好了,下面是在JSP中如下调用。 J>p6')Y6~
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<% B
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CountBean cb=new CountBean(); B0|!s
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); -]kvM
CountCache.add(cb); ;HoBLxb P
out.print(CountCache.list.size()+"<br>"); .l$:0a
CountControl c=new CountControl(); bn6WvC3?
c.run(); sA!$}W
out.print(CountCache.list.size()+"<br>"); 2c1L[]h'
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