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: 9[\$\l
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CountBean.java u@[JX1&3"n
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/* )d?L*X~y'
* CountData.java 5fhe{d"si
* T
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* Created on 2007年1月1日, 下午4:44 pXxpEv
* #J
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* To change this template, choose Tools | Options and locate the template under pB]+c%\
* the Source Creation and Management node. Right-click the template and choose Je~Ybh
* Open. You can then make changes to the template in the Source Editor. ]M9r<x*
*/ ZEU/6.
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package com.tot.count; |f&=9%
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/** 7;:Uv=
* Rwz (20n\^
* @author Q(YQ$i"S
*/ 2Yd;#i)
public class CountBean { {{4Sgb
private String countType; O>L
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int countId; 9"k^:}8.
/** Creates a new instance of CountData */ =dI2j@}c
public CountBean() {} 1|\/2
public void setCountType(String countTypes){ w=75?3c7 F
this.countType=countTypes; 2SVJKX_V+
} z2A1h!Me
public void setCountId(int countIds){ 1:iT#~n
this.countId=countIds; ?`D/#P
} Y]t)k9|vv
public String getCountType(){ };;6706a
return countType; 0j|JyS:}G
} @460r
public int getCountId(){ Gl>_C@n0h
return countId; !tofO|E5
} ::rKW*?
} -}*YfwK
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CountCache.java 41`&/9:"_M
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/* vb Mv8Nk
* CountCache.java ];o[Yn'>o
* ~~'UQnUN4
* Created on 2007年1月1日, 下午5:01 zc#aQ.
* >)PcK
* To change this template, choose Tools | Options and locate the template under U
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* the Source Creation and Management node. Right-click the template and choose w[wrZ:[
* Open. You can then make changes to the template in the Source Editor. </8F
*/ J'>i3eLq
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package com.tot.count; ~<#!yRy>r
import java.util.*; U#!f^@&AB
/** !G3d5d2)C
* 07L1 "
* @author |cE 69UFB
*/ $>fMu
public class CountCache { ^h@1t FF
public static LinkedList list=new LinkedList(); :|?nz$
/** Creates a new instance of CountCache */ WwM/M!98J
public CountCache() {} Ui`Z>,0sFi
public static void add(CountBean cb){ (AnM_s
if(cb!=null){ Xm2p<Xu8h
list.add(cb); UjU*`}k3
} tZ]/?+1G
} *^&2L,w
} +8AGs,
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CountControl.java sh %snLw
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/* gjVKk
* CountThread.java )N4_SA
* #\]:lr{>?4
* Created on 2007年1月1日, 下午4:57 }XiV$[xHd
* .UuCTH;6`
* To change this template, choose Tools | Options and locate the template under n^AQ!wC
* the Source Creation and Management node. Right-click the template and choose 2& l~8,
* Open. You can then make changes to the template in the Source Editor. hs"=>(P)
*/ o4"7i 9+g
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package com.tot.count; q-fxs8+m|
import tot.db.DBUtils; (
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import java.sql.*; !5P\5WF~Y
/** _JjR=
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* 'bXm,Ed
* @author 1c}
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*/ A%pBvULH
public class CountControl{ #X(KW&;m
private static long lastExecuteTime=0;//上次更新时间 .;0?r9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Ol~jq;75
/** Creates a new instance of CountThread */ jCMr[ G=
public CountControl() {} AVys`{*c
public synchronized void executeUpdate(){ $i+
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Connection conn=null; ni@N/Z?!pA
PreparedStatement ps=null; }0P5~]S<5A
try{ i<*{Z~B
conn = DBUtils.getConnection(); xmEmdOoD
conn.setAutoCommit(false); v/E_A3Ay&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;9r `P_r
for(int i=0;i<CountCache.list.size();i++){ 2%'iTXF
CountBean cb=(CountBean)CountCache.list.getFirst(); Xk_xTzJ
CountCache.list.removeFirst(); %!G]H
ps.setInt(1, cb.getCountId()); XJ|CC.]1u
ps.executeUpdate();⑴ jQp7TdvLE$
//ps.addBatch();⑵ 2?9SM@nAY
} EVW{!\8[
//int [] counts = ps.executeBatch();⑶ JEK6Ms;)A
conn.commit(); w}<CH3cx
}catch(Exception e){ ^f-?xXPx
e.printStackTrace(); Q}N.DM@d3
} finally{ oc>ne]_'
try{ v^ a.
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if(ps!=null) { gm63dE>
ps.clearParameters(); Q}a 1P8?S
ps.close(); tf?u ;n
ps=null; WdGjvs
} yk4Huq&2
}catch(SQLException e){} q#$4Kt;
DBUtils.closeConnection(conn); 3:f<cy
} 3JiJ,<,7
} ~@x@uY$5
public long getLast(){ <(YmkOS+
return lastExecuteTime; xbFoXYqgP
} ZLBv\VQ
public void run(){ )2|'`
long now = System.currentTimeMillis(); =#AeOqs( q
if ((now - lastExecuteTime) > executeSep) { cvR|qHNX
//System.out.print("lastExecuteTime:"+lastExecuteTime); !}D!_z,)u
//System.out.print(" now:"+now+"\n"); GB1[`U%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); uM\(#jZ
lastExecuteTime=now; m/)Wn
executeUpdate(); }vRs n-E@
} >bia
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else{ xHv<pza:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'J (4arN
} jJc?/1 jv
} HG2i^y
} E-NuCP%|c
//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 em
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类写好了,下面是在JSP中如下调用。 fA!uSqR$V
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<% T-)Ur/qp
CountBean cb=new CountBean(); $6~D 2K
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \Gh]$sp
CountCache.add(cb); m L#-U)?F
out.print(CountCache.list.size()+"<br>"); [-)N}rL>
CountControl c=new CountControl(); ~VZ)LQ'7
c.run(); 1us-ootsjP
out.print(CountCache.list.size()+"<br>"); _L mDF8Q(
%>