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: uN0fWj]
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CountBean.java L\CM);y
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/* <KPx0g?=b
* CountData.java rB|:r\Z(jG
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* Created on 2007年1月1日, 下午4:44 ,5uDEXpt{
* 8vo7~6yy
* To change this template, choose Tools | Options and locate the template under ibUPd."W
* the Source Creation and Management node. Right-click the template and choose v$/i5kcWx
* Open. You can then make changes to the template in the Source Editor. B_jI!i{N%o
*/ Pm;*Jv%
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package com.tot.count; <[l}^`IC^4
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/** z( [ $,e\
* l8us6
* @author S%#Mu|
*/ h,?Yw+#o"
public class CountBean { u`,R0=<4
private String countType; A_U0HVx_
int countId; K
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/** Creates a new instance of CountData */ N ] /d
public CountBean() {} 3"D00~
public void setCountType(String countTypes){ x+`3G.
this.countType=countTypes; R:x04!}
} [;8fL
public void setCountId(int countIds){ Xb
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this.countId=countIds; #N}}8RL
} sswAI|6ou
public String getCountType(){ 5g7}A`
return countType; W?Abx
} ?+o7Y1 k,
public int getCountId(){ -3U}
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return countId; 7B"aFnK;[J
} |noTIAI
} $:Zxb
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CountCache.java Z i&X ,K~
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/* ED&KJnquWJ
* CountCache.java W\Y
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* O4mWsr
* Created on 2007年1月1日, 下午5:01 S^=/}PT'
* aKr4E3`
* To change this template, choose Tools | Options and locate the template under [c )\?MWW
* the Source Creation and Management node. Right-click the template and choose m]pvJJ@
* Open. You can then make changes to the template in the Source Editor. G=Bj1ss.
*/ Y%8QFM
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package com.tot.count; v3#47F)
import java.util.*; n:z>l,`C]
/** g&5VorGx
* 0k]N%!U
* @author sRI8znus
*/ `P*j~ZLlXN
public class CountCache { /^ 7
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public static LinkedList list=new LinkedList(); XaSl6CH
/** Creates a new instance of CountCache */ >pHvBFa3G
public CountCache() {} 3e1"5~?'<
public static void add(CountBean cb){ h0}-1kVT^
if(cb!=null){ KJZY.7
list.add(cb); _fw'c*j
} <-7Ha_#
} x9s`H)
} 13
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CountControl.java =J\7(0Dz4t
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/* ]xs\,}I%
* CountThread.java mz'8
* n&&y\?n
* Created on 2007年1月1日, 下午4:57 ?id^v 7d
* ]TN}`]
* To change this template, choose Tools | Options and locate the template under .1M>KRSr,
* the Source Creation and Management node. Right-click the template and choose uS.a9
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* Open. You can then make changes to the template in the Source Editor. 'iK*#b8l
*/ :D-vE7
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package com.tot.count; 5@5="lNjS
import tot.db.DBUtils; N`fY%"5U>
import java.sql.*; LnIJw D
/** UkQocZdZ
* FiL
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* @author qILr+zH
*/ 5J3kQ;5Q?
public class CountControl{ '-{jn+,
private static long lastExecuteTime=0;//上次更新时间 oaE3Aa
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]P^ +~
/** Creates a new instance of CountThread */ FA,CBn5%
public CountControl() {} "WL
public synchronized void executeUpdate(){ _bsfM;u.%
Connection conn=null; H8U*oLlc
PreparedStatement ps=null; x$sQ .aT
try{ w"J(sVy4
conn = DBUtils.getConnection(); gUQCKNw
conn.setAutoCommit(false); ?c*d
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~o$=(EC
for(int i=0;i<CountCache.list.size();i++){ Kz;VAH
CountBean cb=(CountBean)CountCache.list.getFirst(); c8MNo'h
CountCache.list.removeFirst(); G&-h,"yo^
ps.setInt(1, cb.getCountId()); UI'eD)WR
ps.executeUpdate();⑴ huE#VY
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//ps.addBatch();⑵ Uy=eHwU?J
} "w1jr 6"
//int [] counts = ps.executeBatch();⑶ <u\G&cd_tA
conn.commit(); Zx0c6d!B
}catch(Exception e){ S/aPYrk>6
e.printStackTrace(); ,"v%
} finally{ 9X~^w_cdk
try{ 1??RX}8[L+
if(ps!=null) { !b=$FOC>
ps.clearParameters(); eS|p3jk;
ps.close(); -)GfSk
ps=null; >6j`ZWab>
} zQJbZ=5Bu"
}catch(SQLException e){} b%F*N r
DBUtils.closeConnection(conn); x&wUPo{
} !bg3
} glpdYg *
public long getLast(){ HIAd"}^
return lastExecuteTime; &gfQZxT
} ~x+w@4)a>
public void run(){ )Ec;kr b+
long now = System.currentTimeMillis(); s+11) ~
if ((now - lastExecuteTime) > executeSep) { @ ri.r1
//System.out.print("lastExecuteTime:"+lastExecuteTime); Fk:(%ci
//System.out.print(" now:"+now+"\n"); /uVB[Tk^
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &0`L; 1R
lastExecuteTime=now; q ^?{6}sy
executeUpdate(); xM,3F jF
} `JCC-\9T_
else{ rO~D{)Nu
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); t30V_`eQ
} A(B2XBS!?
} t Ks0]8tc
} HT'dft #
//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 H#D=vx'
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类写好了,下面是在JSP中如下调用。 <LE>WfmC
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<% QX4I+x~oo\
CountBean cb=new CountBean(); f$L5=V
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); sAxn
;
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CountCache.add(cb); y[vjqfdmU
out.print(CountCache.list.size()+"<br>"); n3w2&
CountControl c=new CountControl(); _)Ms9RN
c.run(); D~Su822
out.print(CountCache.list.size()+"<br>"); |(fWT}tg
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