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: oAgU rl;R
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CountBean.java v9"03=h
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/* @T%8EiV
* CountData.java B-h@\y
* B^Hhrz!
* Created on 2007年1月1日, 下午4:44 xu.TS
* O% 8>siU
* To change this template, choose Tools | Options and locate the template under Lum5Va%0
* the Source Creation and Management node. Right-click the template and choose `5SQ4
* Open. You can then make changes to the template in the Source Editor. HL%|DCo
*/ ,L\>mGw
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package com.tot.count; <OTx79m
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/** q
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* c~u91h?
* @author !M}ZK(
*/ YL/B7^fd8
public class CountBean { Hb\['VhzM
private String countType; t:YMF$Z
int countId; KM/c^a4V
/** Creates a new instance of CountData */ ufJHC06
public CountBean() {} q<Y#-Io%3
public void setCountType(String countTypes){ |%@pjJ`3
this.countType=countTypes; P52qt N<
} #9t3 <H[
public void setCountId(int countIds){ FiKGB\_]
this.countId=countIds; |Q$Dj!!1P
} bzh:
public String getCountType(){ %*OQH?pyx}
return countType; 0zE(:K
} Iz8gZ:rd0
public int getCountId(){ 2E0oLl[
return countId; D~)bAPAD
} 3x)jab
} D!mx &O9
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CountCache.java \7G.anY
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/* yC[Q-P *rG
* CountCache.java d
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* 9yp'-RKjw
* Created on 2007年1月1日, 下午5:01 4P?@NJp
* bJ]blnH
* To change this template, choose Tools | Options and locate the template under B1TWOl?d{
* the Source Creation and Management node. Right-click the template and choose $V;0z~&!'
* Open. You can then make changes to the template in the Source Editor. _Zus4&'
*/ P?J\pJ1|7
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package com.tot.count; =m6<H
import java.util.*; aa}U87]k
/** M:oZk&cs
* f=-R<l
* @author VYkUUp
*/ @_
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public class CountCache { 6Oy6r
public static LinkedList list=new LinkedList(); ohi0_mBz
/** Creates a new instance of CountCache */ #!t6'*
public CountCache() {} {/i&o
public static void add(CountBean cb){ *RFBLCt
if(cb!=null){ r-,u)zf"
list.add(cb); mpD[k9`x#
} r |2{(+
} c"P:p%\m&u
} S}6xkX
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CountControl.java :(;ho.zz
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/* 7#C3E$gn?
* CountThread.java ,%U\@*6=
* Y^eF(
* Created on 2007年1月1日, 下午4:57 5YLc4z*
* qfF2S
* To change this template, choose Tools | Options and locate the template under lqvP
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* the Source Creation and Management node. Right-click the template and choose . dJBv
* Open. You can then make changes to the template in the Source Editor. s?PB ]Tr
*/ =z\/xzAwX
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package com.tot.count; mt4X
import tot.db.DBUtils; 5:%`&B\
import java.sql.*; 4c<\_\\ck
/** )\J~KB4
* T1;>qgp4b
* @author u56F;y
*/ 1i;Cw/mr
public class CountControl{ fvj
private static long lastExecuteTime=0;//上次更新时间 yh{U!hG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 G-'CjiMu
/** Creates a new instance of CountThread */ izR#XeBm
public CountControl() {} nI/kX^Pd
public synchronized void executeUpdate(){ ( +(bw4V/
Connection conn=null; zEDN^K '
PreparedStatement ps=null; w@H@[x
try{ K;]Dh?
conn = DBUtils.getConnection(); 9&{HD
conn.setAutoCommit(false); PNH>LT^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); f/U~X;
for(int i=0;i<CountCache.list.size();i++){ (#+81 Dr
CountBean cb=(CountBean)CountCache.list.getFirst(); y w:=$e5
CountCache.list.removeFirst(); ON"p^o>/_?
ps.setInt(1, cb.getCountId()); AJ
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ps.executeUpdate();⑴ i:H]Sb)<b
//ps.addBatch();⑵ x^McUfdr|
} ol}}c6
//int [] counts = ps.executeBatch();⑶ zIr4!|X
conn.commit(); G6s3\de#U
}catch(Exception e){ |Rz}bsrZ
e.printStackTrace(); #I#_gjJkx
} finally{ +1c[!;'
try{ %DKC/%
if(ps!=null) { 8F/zrPG
ps.clearParameters(); |][PbN
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ps.close(); 3U*4E?g
ps=null; 0O(V y y
} (O/W`qo
}catch(SQLException e){} oSl}A,aQ(
DBUtils.closeConnection(conn); [d=BN ,?
} |}@teN^J*U
} bVr`a*EM
public long getLast(){ lU.aDmy<
return lastExecuteTime; |(uo@-U
} V-18~+F~"a
public void run(){ n!U1cB{
long now = System.currentTimeMillis(); 6n
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if ((now - lastExecuteTime) > executeSep) { w I[Hoi
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//System.out.print("lastExecuteTime:"+lastExecuteTime); Nhtc^DX
//System.out.print(" now:"+now+"\n"); WLH ;{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &:~9'-O
lastExecuteTime=now; /*Gbl
executeUpdate(); z6fY_LL
} yF-`f
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else{ 3dgPP@7d$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); pL: r\Y:R
}
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} a..LbQQ
} KBA&s
//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 Z>*a:|
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类写好了,下面是在JSP中如下调用。 sTvw@o*
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<% U"Y/PBs,
CountBean cb=new CountBean(); 'tt4"z2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); zL3I!& z2
CountCache.add(cb); TRr%]qd{Hr
out.print(CountCache.list.size()+"<br>"); e@PY(#ru
CountControl c=new CountControl(); u ^M'[<{
c.run(); 7gREcL2
out.print(CountCache.list.size()+"<br>"); I0G[K~gb
%>