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: --h\tj\U
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CountBean.java @SfQbM##%
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/* >$q
* CountData.java <4r8H-(%
* i)#-VOhX)
* Created on 2007年1月1日, 下午4:44 0X)vr~`
* *)m:u :
* To change this template, choose Tools | Options and locate the template under zlMh^+rMX
* the Source Creation and Management node. Right-click the template and choose C-M_:kQ[U
* Open. You can then make changes to the template in the Source Editor. Ejug2q
*/ tYA@J[" ^
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package com.tot.count; <rC%$tr
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/** 20Zxv!
*
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* @author Ow0>qzTg
*/ eV7;#w<]
public class CountBean { 9xA4;)36
private String countType;
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int countId; W3:j Z:
/** Creates a new instance of CountData */ r1!1u7dr
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public CountBean() {} FJ_JaIby
public void setCountType(String countTypes){ &'6/H/J
this.countType=countTypes; n#!c!EfG
} `gSMb
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public void setCountId(int countIds){ l";Yw]:^
this.countId=countIds; <]Td7-n
} .7Mf(1:
public String getCountType(){ ~ QRjl
return countType; |>Q>d8|k
} N~/'EaO
public int getCountId(){ YsmRY=3
return countId; =l(euBb
} .xIAep_
} 4cQP+ n
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CountCache.java ebA95v`Vms
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/* 4/
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* CountCache.java /&Q{B f
* x2v0cR"KL
* Created on 2007年1月1日, 下午5:01 (d4btcg
* tW/k
* To change this template, choose Tools | Options and locate the template under @)>Z+g
* the Source Creation and Management node. Right-click the template and choose UZ<K'H,q
* Open. You can then make changes to the template in the Source Editor. oq7G=8gTp
*/ HH*y$
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package com.tot.count; Q`F1t
import java.util.*; WW:G(
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/** Q6m8N
* Vn5T Jw
* @author
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*/ A}ZZQ
public class CountCache { g8O6
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public static LinkedList list=new LinkedList(); pGD@R=8
/** Creates a new instance of CountCache */ z&;8pZr
public CountCache() {} g}MUfl-L
public static void add(CountBean cb){ a``|sn9
if(cb!=null){ +q&Hj|;8r
list.add(cb); ~,/@]6S&Y
} xhP~]akHN7
} 4Ly>x>b<
} 1AAyzAP9`
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CountControl.java Z3]I^i
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/* \Kf\%Q
* CountThread.java uw \@~ ,d
* * zp tbZ
* Created on 2007年1月1日, 下午4:57 +vkmS
* uHU@j(&c
* To change this template, choose Tools | Options and locate the template under ,D{7=mDVm
* the Source Creation and Management node. Right-click the template and choose tA#Pc6zBuC
* Open. You can then make changes to the template in the Source Editor. w(@r-2D"
*/ IV,4BQ$
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package com.tot.count; %)j&/QdzF&
import tot.db.DBUtils; R!dC20IMvH
import java.sql.*; nL
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/** 'dwW~4|B
* hC2Fup1 @
* @author CNN9a7
*/ u ON(LavB
public class CountControl{ ZR!8hw8
private static long lastExecuteTime=0;//上次更新时间 HAn{^8"@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *$=i1w
/** Creates a new instance of CountThread */ ]LB_ @#
public CountControl() {} h]<S0/
public synchronized void executeUpdate(){ *X.1b!
Connection conn=null; u=0O3-\h
PreparedStatement ps=null; ~YH?wdT
try{ =\6)B{#T
conn = DBUtils.getConnection(); Um+_S@h
conn.setAutoCommit(false); h~>1-T8
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $!O@Z8B
for(int i=0;i<CountCache.list.size();i++){ -K/+}4i3N
CountBean cb=(CountBean)CountCache.list.getFirst(); h,{Q%sqO
CountCache.list.removeFirst(); h:fiUCw
ps.setInt(1, cb.getCountId()); "L2*RX.R
ps.executeUpdate();⑴ 5e7Y M@ng
//ps.addBatch();⑵ 0%bCP/
} bqbG+g
//int [] counts = ps.executeBatch();⑶ 5t:Zp\$+`
conn.commit(); .{ v$;g
}catch(Exception e){ \dHqCQ
e.printStackTrace(); r<0E[~
} finally{ ebze_:
try{ k>ErDv8
if(ps!=null) { UPH#~D!
ps.clearParameters(); &m3-][!n
ps.close(); @V:K]M 5
ps=null; GDLi?3q
} V,KIi_Z
}catch(SQLException e){} CFFb>d
DBUtils.closeConnection(conn); eKr>>4,-P
} 4.,EKw3
} [ K?
public long getLast(){ 9p8ajlYg,
return lastExecuteTime; _&l8^MD
} jV2H61d
public void run(){ ?J2{6,}O*.
long now = System.currentTimeMillis(); w>2lG3H<
if ((now - lastExecuteTime) > executeSep) { P|Aac,nE+^
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,g?ny<#o
//System.out.print(" now:"+now+"\n"); SNqSp.>-U"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &6\&McmkX
lastExecuteTime=now; "]"0d[d
executeUpdate(); cB,^?djJ3
} Fizrsr 6%
else{ 0#NMNZ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); i6paNHi*
} ,t 2CQ
} P"NI> HM
} <pk*z9
//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 l-w4E"n3
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类写好了,下面是在JSP中如下调用。 L<V20d9
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<% L9/'zhiZBx
CountBean cb=new CountBean(); :kHk'.V1(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); w5z]=dN
CountCache.add(cb); d_
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out.print(CountCache.list.size()+"<br>"); Mg\588cI
CountControl c=new CountControl(); k$v7@|Aw
c.run(); c&T5C,]
out.print(CountCache.list.size()+"<br>"); 7ZI{A*^vB
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