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: @%okaj#IO
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CountBean.java TuT=
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/* m0K2 p~
* CountData.java uc
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* vcUM]m8k
* Created on 2007年1月1日, 下午4:44 -1Ki7|0,
* z@40g)R2A
* To change this template, choose Tools | Options and locate the template under RI].LB_
* the Source Creation and Management node. Right-click the template and choose Tr+Y@]"
* Open. You can then make changes to the template in the Source Editor. JZ*?1S>
*/ <GU(/S!}
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package com.tot.count; O"w_sw
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/** Vf* B1Zb
* ]4pC\0c
* @author )fcpE,g'
*/ [;\<
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public class CountBean { r4qV}-E
private String countType; ^*T{-U'
int countId;
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/** Creates a new instance of CountData */ D_`)T;<Sp
public CountBean() {} w+ )GM
public void setCountType(String countTypes){ [}B{e=`!
this.countType=countTypes; {hp@j#
} S+=@d\S}"
public void setCountId(int countIds){ D"><S<C\C
this.countId=countIds; &rE l
} oz7udY=]0
public String getCountType(){ OTbjZ(
return countType; vnT
} G7#~=W
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public int getCountId(){ xn#I7]]G
return countId; `E%d$
} x[<#mt
} ^.aEKr
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CountCache.java <UHf7:0V
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/* iY`7\/H!L
* CountCache.java vVRCM
* K>E!W!-PJ
* Created on 2007年1月1日, 下午5:01 XsCbJ[Z_?q
* 8YkH
* To change this template, choose Tools | Options and locate the template under i7E7%~S
* the Source Creation and Management node. Right-click the template and choose Q? |M BTo
* Open. You can then make changes to the template in the Source Editor. k{&E}:A
*/ =cX"gI[
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package com.tot.count; vG=$UUh@~
import java.util.*; *`/@[S2,cu
/** g{.@|;d<p
* <\Dl#DH
* @author )=y6s^}
*/ |Szr=[
public class CountCache { ~.=HN}E
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ $XzlW=3y
public CountCache() {} )Syf5I
public static void add(CountBean cb){ G\+MT(&5
if(cb!=null){ [1X5r<(W5
list.add(cb); Jywz27j
} \^Q)`Lqp:g
} Z#t.wWSq
} E<[
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CountControl.java eyp\h8!u_
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/* bGLp0\0[
* CountThread.java >.sN?5}y
* z:?
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* Created on 2007年1月1日, 下午4:57 {dH<Un(4Z
* Z4tq&^ :c=
* To change this template, choose Tools | Options and locate the template under <JuJ`t
* the Source Creation and Management node. Right-click the template and choose 3S21DC@Y
* Open. You can then make changes to the template in the Source Editor. xVo)!83+Q
*/ "uNxKLDB
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package com.tot.count; _A~gqOe
import tot.db.DBUtils; \r&@3a.>
import java.sql.*; n Fn`>kQ
/** g#&##f
* {:j!@w 3
* @author d|HM
*/ AMiFsgBj
public class CountControl{ _\6(4a`,
private static long lastExecuteTime=0;//上次更新时间 M?CMN.Dw
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ph+tk5k
/** Creates a new instance of CountThread */ tOVm~C,R
public CountControl() {} 0(6`dr_
public synchronized void executeUpdate(){ gx.]4v
Connection conn=null; 3Q"+
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PreparedStatement ps=null; Tj~#Xc
try{ r\D8_S_
conn = DBUtils.getConnection(); :cz]8~i\
conn.setAutoCommit(false); c3BL2>c
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); NGzqiu"J
for(int i=0;i<CountCache.list.size();i++){ {iteC
CountBean cb=(CountBean)CountCache.list.getFirst(); 1Ac1CsK*
CountCache.list.removeFirst(); g0$k_
ps.setInt(1, cb.getCountId()); f@g
ps.executeUpdate();⑴ 6XU5T5+P^
//ps.addBatch();⑵ H2KY$;X[
} 2$UR"P
//int [] counts = ps.executeBatch();⑶ q{(&:~M
conn.commit(); !Z)^c&
}catch(Exception e){ B)NB6dCp
e.printStackTrace(); (ytkq(
} finally{ I(S6DkU
try{ e4LNnJU\|
if(ps!=null) { QQcj"s
ps.clearParameters(); (HxF\#r?
ps.close(); ^%^0x'"
ps=null; 9jO+ew
} U$Z}<8
}catch(SQLException e){} oa7Hx<Y
DBUtils.closeConnection(conn); (`xnA~BN
} dkC / ?R
} B\yq%m
public long getLast(){ pP&M]'
return lastExecuteTime; ^a5>`W
} {HDlv[O%
public void run(){ z#/*LP#oY
long now = System.currentTimeMillis(); c^k.
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if ((now - lastExecuteTime) > executeSep) { iB-s*b<`~
//System.out.print("lastExecuteTime:"+lastExecuteTime); K>eG5tt
//System.out.print(" now:"+now+"\n"); 1=.?KAXR
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); b>EUa> h
lastExecuteTime=now; *5)!y
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executeUpdate(); >$F]Ss)$
} ]vErF=[U,
else{ RkM! BcB
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); b>WT-.b0
} ) P])0Y-
} I-"{m/PEdg
} n5/Q)*e0'#
//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 (v}:
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类写好了,下面是在JSP中如下调用。 bS<p dOX_
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<% Awh)@iTL
CountBean cb=new CountBean(); mws.)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); A@r,A?(
CountCache.add(cb); G.T1rUh=
out.print(CountCache.list.size()+"<br>"); !HYqM(|{.
CountControl c=new CountControl(); xcA:Q`c.{
c.run(); 4N&}hOM'S
out.print(CountCache.list.size()+"<br>"); 2D"/k'iA
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