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: no`> r}C
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CountBean.java q,->E<8
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/* <:gNx%R
* CountData.java m-h+UKt
* }X;LR\^u[f
* Created on 2007年1月1日, 下午4:44 YlP8fxS
* <6(&w9WY
* To change this template, choose Tools | Options and locate the template under Co%EJb"tk
* the Source Creation and Management node. Right-click the template and choose 8G6[\P3fQ
* Open. You can then make changes to the template in the Source Editor. }-8ZSWog6f
*/ 8E:d!?<^&I
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package com.tot.count; q=+AN</
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/** ZY Ci&l
* W.O]f.h
* @author fkjo
*/ *>%tx k:)
public class CountBean { kTQvMa-X9D
private String countType; OU /=w pt
int countId; u+
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/** Creates a new instance of CountData */ Tz"Xm/Gy
public CountBean() {} JJ=%\j
public void setCountType(String countTypes){ 7B"*< %<
this.countType=countTypes; $Z2Y% z6y
} [$bK%W{f
public void setCountId(int countIds){ UW?(-_8
this.countId=countIds; =Co[pt
} q0a8=o"|
public String getCountType(){ s;[OR
return countType; 0K*|B.O
} 0qPbmLMK
public int getCountId(){ }+wvZq +c
return countId; -ghmLMS%t
} zZ11J0UI
} ^zs]cFN#%
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CountCache.java F CbU> 1R
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/* /`b(} m
* CountCache.java 2xx
* c<c"n'
* Created on 2007年1月1日, 下午5:01 P
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* 6|O2i j-J
* To change this template, choose Tools | Options and locate the template under ;vDjd2@
* the Source Creation and Management node. Right-click the template and choose Oz:J8l%
* Open. You can then make changes to the template in the Source Editor. #,4CeD|(D,
*/ )8rN
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package com.tot.count; VYj*LiR
import java.util.*; lNQ8$b
/** oieZopYA
* Up/s)8$.
* @author n=+K$ R
*/ U fzA/
public class CountCache { M&/([>Q
public static LinkedList list=new LinkedList(); 6S2u%-]
/** Creates a new instance of CountCache */ {ejJI/o0
public CountCache() {} />EH]-|
public static void add(CountBean cb){ 1;Dug
if(cb!=null){ *NEA(9
list.add(cb); Zc<fopi h
} 0<{zW%w
} `]0E)
} a1 I"Sh
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CountControl.java av.L%l&d
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/* sr*3uI-)L
* CountThread.java rphfW:
* GF3"$?Cw
* Created on 2007年1月1日, 下午4:57 vp>,}nx4
* g3`:d)|
* To change this template, choose Tools | Options and locate the template under 4.^1D';(
* the Source Creation and Management node. Right-click the template and choose jQgy=;?Lwm
* Open. You can then make changes to the template in the Source Editor. iO 9fg
*/ fF"\$Ny
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package com.tot.count; Gh:hfHiG
import tot.db.DBUtils; r@XH=[:
import java.sql.*; ?<l,a!V'6
/** z'(][SB
* # RG/B2
* @author )0Lno|l
*/ ^Iz(V2
public class CountControl{ x2KIGG^
private static long lastExecuteTime=0;//上次更新时间 ;Rz+4<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ZMI!Sl
/** Creates a new instance of CountThread */ etPb^$
public CountControl() {} EzXGb
public synchronized void executeUpdate(){ J=*X%^jX9Z
Connection conn=null; <H,q( :pM
PreparedStatement ps=null; PS13h_j
try{ Buue][[
conn = DBUtils.getConnection(); _2wU(XYH
conn.setAutoCommit(false); !='?+Ysxs
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); S"/M+m+ ]
for(int i=0;i<CountCache.list.size();i++){ m-M.F9R
CountBean cb=(CountBean)CountCache.list.getFirst(); nisW<Q`uB
CountCache.list.removeFirst(); vwlPFrLl
ps.setInt(1, cb.getCountId()); dCF!.
ps.executeUpdate();⑴ !5/jDvh
//ps.addBatch();⑵ }aPx28:/
} |Zn|?#F
//int [] counts = ps.executeBatch();⑶ $eI=5
conn.commit(); [KT'aGK$
}catch(Exception e){ D(m2^\O[
e.printStackTrace(); %s^2m"ca}=
} finally{ ~; emUU
try{ !@r1B`]j+"
if(ps!=null) { 2}ttCm
ps.clearParameters(); KXAh0A?&+
ps.close(); exnFy-
ps=null; ^o*$OM7x
} C_&-2Z
}catch(SQLException e){} ?_!} lg
DBUtils.closeConnection(conn); ;Tn$c70
} "-pQL )f
} 4t%g:9]vr
public long getLast(){ aMxg6\8
return lastExecuteTime; Q1?0R<jOU
} ;~2RWj=-
public void run(){ w=UFj
long now = System.currentTimeMillis(); )o:%Zrk
if ((now - lastExecuteTime) > executeSep) { /O@dqEbc
//System.out.print("lastExecuteTime:"+lastExecuteTime); OF4iGFw
//System.out.print(" now:"+now+"\n"); (.:!_OB0N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); O e-FI+7
lastExecuteTime=now; 7B|ddi7Q>
executeUpdate(); %`kO\q_
} 7V^\fh5~
else{ E&}@P0^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sNet[y:O3
} J <<Ph
} Ic%c%U=i
} 2=&4@c|cn
//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 Stzv
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类写好了,下面是在JSP中如下调用。 WB:NV=&^
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<% .ykCmznf*
CountBean cb=new CountBean(); u@;6r"8q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); LQ7.RK
CountCache.add(cb); Xx=jN1=,
out.print(CountCache.list.size()+"<br>"); U]aH4N
CountControl c=new CountControl(); K>"]*#aBv
c.run(); ?"d25LyN
out.print(CountCache.list.size()+"<br>"); WSt&?+Y
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