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: %hQMC'c
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CountBean.java 61+pryW%g
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/* fs3-rXoB
* CountData.java L=$?q/=-
* 8MeO U
* Created on 2007年1月1日, 下午4:44 orQV'
* R%)2(\
* To change this template, choose Tools | Options and locate the template under "x.6W!
* the Source Creation and Management node. Right-click the template and choose }[KDE{,V
* Open. You can then make changes to the template in the Source Editor. Qw6KX#n
*/ l)i&ATvCE
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package com.tot.count; !rsa4t@t
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/** G>[
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* 0V>ESyae5
* @author @`IXu$Wm(
*/ C"U[ b%
public class CountBean { ebO`A2V'(
private String countType; Ere?d~8
int countId; ,#P,B;r~
/** Creates a new instance of CountData */ 3XAp Y'
public CountBean() {} 2xL!PR-
public void setCountType(String countTypes){ SLQ\Y%F
this.countType=countTypes; z\Pe{J
} t?]\M&i&
public void setCountId(int countIds){ h V|v6 _
this.countId=countIds; "}'8`k+d
} KdOh'OrT9.
public String getCountType(){ KrdZEi vb
return countType; 7x[LF ^o
} Ism^hyL
public int getCountId(){ /RJ6nmN@}
return countId; >-_:*/66!
} l)tTg+:
} F,p`-m[q
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CountCache.java {h/OnBwG
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/* YVQ_tCC_!
* CountCache.java "*Lj8C3|n
* 8iMF 8\
* Created on 2007年1月1日, 下午5:01 E;6Y? vJ
* lv<iJH\
* To change this template, choose Tools | Options and locate the template under ]&Y#)ebs
* the Source Creation and Management node. Right-click the template and choose N5pinR5 H
* Open. You can then make changes to the template in the Source Editor.
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*/ zAeGkP ~K
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package com.tot.count; 0K=Qf69Y
import java.util.*; zW*}`S"
/** !GlnQ`T
* P'a0CE%
* @author Q)x?B]b-
*/ Uj4Lu
public class CountCache { Yw6DJY
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ !UBy%DN~k
public CountCache() {} "KMLk
public static void add(CountBean cb){ ,\BVV,
if(cb!=null){ NJn&>/vM
list.add(cb); T?W[Z_D
} 2{Wo-B,wt~
} BX@pt;$ek7
} w-
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CountControl.java .CVUEK@Z4
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/* "Kyifw?
* CountThread.java _Ny8j~
* cvKV95bn
* Created on 2007年1月1日, 下午4:57 Y.q>EUSH
* ?3`q+[:
* To change this template, choose Tools | Options and locate the template under ;4!=DFbU
* the Source Creation and Management node. Right-click the template and choose #MUiL=
* Open. You can then make changes to the template in the Source Editor. }<SNO)h3
*/ 3@&bxYXm
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package com.tot.count; GP* +
import tot.db.DBUtils; Q4X7Iu:
import java.sql.*; mKV'jm0
/** :v`o6x8
* \3r3{X
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* @author [!G)$<
*/ ^"1TPd|
public class CountControl{ p"KU7-BfvC
private static long lastExecuteTime=0;//上次更新时间 UV4u.7y
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 X6xx2v%D
/** Creates a new instance of CountThread */ )%s +?
public CountControl() {} o
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public synchronized void executeUpdate(){ i`+B4I8[
Connection conn=null; I0DM=V>;
PreparedStatement ps=null; BBvZeG $Y
try{ }'lNi^"XL
conn = DBUtils.getConnection(); P<u"97@8a
conn.setAutoCommit(false); 27>a#vCT
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); vh
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for(int i=0;i<CountCache.list.size();i++){ &s:=qQa1
CountBean cb=(CountBean)CountCache.list.getFirst(); f/ajejYo?,
CountCache.list.removeFirst(); hY+R'9
ps.setInt(1, cb.getCountId()); Y;,Hzmbs6w
ps.executeUpdate();⑴ a+41Ojv (
//ps.addBatch();⑵ %w7m\nw@
} .B>B`q;B
//int [] counts = ps.executeBatch();⑶ 0 O~p7D
conn.commit(); azo0{`S?
}catch(Exception e){ x5OC;OQc
e.printStackTrace(); Zm(dY*z5:J
} finally{ o 7G> y#Y
try{ (;}tf~~r
if(ps!=null) { ?U_9{}r
ps.clearParameters(); dv7<AJ
ps.close(); &x0C4Kh
ps=null; ,GrB'N{8e
} `U{mbw,
}catch(SQLException e){} .^[_V
DBUtils.closeConnection(conn); gDCOLDM
} t\r:E2
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} Ax!Gu$K2o
public long getLast(){ =XT)J6z^"
return lastExecuteTime; WA.AFt
} gi]ZG
public void run(){ ]` ]g@v
long now = System.currentTimeMillis(); 5j{Np,K
if ((now - lastExecuteTime) > executeSep) { :.iyR
//System.out.print("lastExecuteTime:"+lastExecuteTime); %6ub3PLw8
//System.out.print(" now:"+now+"\n"); xNpg{cQ=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); \iU] s\{).
lastExecuteTime=now; "&lN\&:
executeUpdate(); #U=;T]!'$
} }"zC
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else{ 5]"SGP
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); M3pjXc<O
} T&xt`|
} 7>i2OBkAhB
} {J]-<:XD
//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 d~*TIN8Ke~
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类写好了,下面是在JSP中如下调用。 6)e5zKW!?
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<% ._CP%
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CountBean cb=new CountBean(); |dmh
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); dDtFx2(R
CountCache.add(cb); 0^~\COa
out.print(CountCache.list.size()+"<br>"); nl1-kB)$e|
CountControl c=new CountControl(); Ip?]K*sq
c.run(); rt4Z;
out.print(CountCache.list.size()+"<br>"); g4&jo_3:p
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