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: Vh=10Et
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CountBean.java $IUe](a{d
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/* w`ebZa/j
* CountData.java d^pzMaCI
* .Aj4?AXWc
* Created on 2007年1月1日, 下午4:44 H+lBb$
* [ 'aSPA
* To change this template, choose Tools | Options and locate the template under `?P)RS30
* the Source Creation and Management node. Right-click the template and choose m}`!FaB #
* Open. You can then make changes to the template in the Source Editor. nz+k ,
*/ U}hQVpP#
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package com.tot.count; T3H\KRe6
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/** t:$^iUrx
* z"D'rHxy
* @author Lgr(j60s
*/ q#pD}Xe$
public class CountBean { 2":{3=oW~
private String countType; 3pU/Zbb,:
int countId; {&3{_Ml
/** Creates a new instance of CountData */ S1SsJo2\
public CountBean() {} 5|:t$
public void setCountType(String countTypes){ }:SWgPfc
this.countType=countTypes; `!- w^~c
} V\|V1c
public void setCountId(int countIds){ O>
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this.countId=countIds; Z2@_F7cXt
} iC(&U YL
public String getCountType(){ $e#V^dph
return countType; 5,vw%F-m
} ^(79SOZC
public int getCountId(){ V)q|U6R
return countId; {PBm dX
} D^dos`L0b
} fC|NK+Xd`
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CountCache.java ais@|s;
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/* "1I\~]]
* CountCache.java @vHj>N
* ]'q"Kw/10
* Created on 2007年1月1日, 下午5:01
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* jt5:rWB
* To change this template, choose Tools | Options and locate the template under a|Yry
* the Source Creation and Management node. Right-click the template and choose CQ;.}=j
,
* Open. You can then make changes to the template in the Source Editor. |g)/6jG<-
*/ ;nx? 4f+6h
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package com.tot.count; T>P[0`*)
import java.util.*; rP%B#%;S"
/** SOg>0VH)
* 3OZu v};k
* @author Z4VNm1qs
*/ md
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public class CountCache { <0sT
public static LinkedList list=new LinkedList(); GI.=\s
/** Creates a new instance of CountCache */ B QxU~s
public CountCache() {} 3{/[gX9
public static void add(CountBean cb){ XSBh+)0Ww
if(cb!=null){ a]]>(Txc
list.add(cb); myq:~^L
;
} LFwRTY,G
} | >
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} ]:g;S,{
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CountControl.java 'O:QS)
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/* 9$Dsm@tX
* CountThread.java pVN) k
* (U?*Z/
* Created on 2007年1月1日, 下午4:57 wgPkSsuBuC
* !8jr $
* To change this template, choose Tools | Options and locate the template under N.1@!\z@@
* the Source Creation and Management node. Right-click the template and choose h+d \u
* Open. You can then make changes to the template in the Source Editor. u&-Zh@;Q7
*/ 'h*^;3@*
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package com.tot.count; I
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import tot.db.DBUtils; XLq%nVBM8\
import java.sql.*; Gm1[PAj
/** y/9aI/O'
* C]01(UoSZ
* @author D-KQRe2@
*/ aK+jpi4?
public class CountControl{ I UZ@n0/T
private static long lastExecuteTime=0;//上次更新时间 Xg^9k00C
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Tm) (?y
/** Creates a new instance of CountThread */ -ufO,tJRLL
public CountControl() {} tqYwPSr
public synchronized void executeUpdate(){ &i{>Li
Connection conn=null; 3*<?'O7I0
PreparedStatement ps=null; 5vSJjhS
try{ &:@)roCR
conn = DBUtils.getConnection(); |G(9mnZ1
conn.setAutoCommit(false); @!np
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "j*{7FBqk
for(int i=0;i<CountCache.list.size();i++){ .$~zxd#zo
CountBean cb=(CountBean)CountCache.list.getFirst(); jM07&o]D
CountCache.list.removeFirst(); :=cZ,?PQp1
ps.setInt(1, cb.getCountId()); c7~>uNgJ
ps.executeUpdate();⑴ @w[2 BaDt
//ps.addBatch();⑵ drkY~!a
} bw[s<z|LKA
//int [] counts = ps.executeBatch();⑶ 9L+g;Js$4
conn.commit(); sgxD5xj}4
}catch(Exception e){ zQ>|`0&8
e.printStackTrace(); r!C#PiT}I
} finally{ YYs/r
try{ HQ0fY
if(ps!=null) { 2Y-NxW^]
ps.clearParameters(); }j\_XaB
ps.close(); y}
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ps=null; a 9H^e<g
} ;jZfVRl
}catch(SQLException e){} E(p*B8d
DBUtils.closeConnection(conn); qh)10*FB
} !M*$pQi}
} XI/LVP,.
public long getLast(){ =bgu2#%Z
return lastExecuteTime; X8uAwHa6F
} y(92 Th$
public void run(){ EG;y@\]
long now = System.currentTimeMillis(); GFX$vn-/F
if ((now - lastExecuteTime) > executeSep) { A^3M~
//System.out.print("lastExecuteTime:"+lastExecuteTime); I/vQP+w O
//System.out.print(" now:"+now+"\n"); ze_q+Z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Hsl0|jy(/
lastExecuteTime=now; /$Ca}>
executeUpdate(); 7,BULs\g
} L!l`2[F|
else{ kWW$*d$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); XhEJF !
} + _"AF|
} ]ur_G`B
} |9*8u>|RC
//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 }\Ri:&?
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类写好了,下面是在JSP中如下调用。 b>]MZhLJe
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<% w;=g$Bn
CountBean cb=new CountBean(); *%p`Jk-U
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); JQ"R%g`8
CountCache.add(cb); g\~n5=-D
out.print(CountCache.list.size()+"<br>"); *74VrAo
CountControl c=new CountControl(); lD41+x7
c.run(); ?#]wxH,
out.print(CountCache.list.size()+"<br>"); ^Yg}>?0
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