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: PPO*&=!]
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CountBean.java D+?/MrP
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/* s>(OK.o
* CountData.java Xdj` $/RI
* >2tQ')%DJ
* Created on 2007年1月1日, 下午4:44 '"&M4.J{
* q eLfO
* To change this template, choose Tools | Options and locate the template under }}y$T(:l
* the Source Creation and Management node. Right-click the template and choose X@KF}x's
* Open. You can then make changes to the template in the Source Editor. "Mzb
*/ c}GmS@
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package com.tot.count; "&*O7cs$pA
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/** -(9>{!",J
* %D_2;
* @author m UY+v>F
*/ `s93P^%
public class CountBean { ]V*s-och'
private String countType; $qG;^1$
int countId; cM%I5F+n
/** Creates a new instance of CountData */ _$%.F|:
public CountBean() {} _7r<RZ
public void setCountType(String countTypes){ RGFanP
this.countType=countTypes; "L^]a$&
} a^_\ #,}
public void setCountId(int countIds){ 0nUcUdIf+
this.countId=countIds; F#_JcEE
} U@21N3_@_
public String getCountType(){ SyFw
return countType; yJ*`OU#
} 21'I-j
public int getCountId(){ tE3#Uq
return countId; [. Vy
} Z5iP1/&D
} |O3wAxc3W
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CountCache.java +bpUb0.W
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/* &R+/Ie#0dz
* CountCache.java ;8\w$SPP
* _b8&$\>
* Created on 2007年1月1日, 下午5:01 ^R- -&{I
* jMv qKJ(<
* To change this template, choose Tools | Options and locate the template under ?'ID7mL
* the Source Creation and Management node. Right-click the template and choose !5I;3EN
* Open. You can then make changes to the template in the Source Editor. EH{m~x[Ei
*/ ~L\KMB/9e=
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package com.tot.count; -X+G_rY
import java.util.*; %(lr.9.]H
/** R-8>,
* \]RPxM:_>
* @author 3!E*h0$}
*/ i) v
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public class CountCache { <q@/Yy32
public static LinkedList list=new LinkedList(); #1fT\aP
/** Creates a new instance of CountCache */ t;005]'Mp
public CountCache() {} )e&U'Fx
public static void add(CountBean cb){ n;&08M5an}
if(cb!=null){ ILi{5L
list.add(cb); ,z<J`n
} E4;vC ?K{
} 8~*<s5H
} ~[n]la
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CountControl.java SOE5`
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/* B(tLV9B3Q
* CountThread.java C\"nlNKw
* )F_vWbg
* Created on 2007年1月1日, 下午4:57 WUOoK$I~K
* A^lJlr:_`
* To change this template, choose Tools | Options and locate the template under sG-$d\
1d
* the Source Creation and Management node. Right-click the template and choose 8<V6W F`e
* Open. You can then make changes to the template in the Source Editor. NGQBOV
*/ A|jmp~@K)+
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package com.tot.count; '-9B`O,&
import tot.db.DBUtils; #snwRW>=[
import java.sql.*; t
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/** =iJfz
* xvo""R/g8
* @author pJ8;7u
*/ U\OfB'Dn
public class CountControl{ TCShS}q;%
private static long lastExecuteTime=0;//上次更新时间 z[Sq7bbYO
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 j v9DQr
/** Creates a new instance of CountThread */ Dp1FX"a)
public CountControl() {} VpmwN`
public synchronized void executeUpdate(){ gbvM2
Connection conn=null; _0HCtx ;
PreparedStatement ps=null; R1'tW=
try{ kyV!ATL1F
conn = DBUtils.getConnection(); vh+ '
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conn.setAutoCommit(false); %3p~5jhm1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }
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for(int i=0;i<CountCache.list.size();i++){ nV`n=x
CountBean cb=(CountBean)CountCache.list.getFirst(); *xHj*
CountCache.list.removeFirst(); =AaTn::e/
ps.setInt(1, cb.getCountId()); }ACWSk WK
ps.executeUpdate();⑴ (!'=?B "
//ps.addBatch();⑵ .`w[A
} ad
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//int [] counts = ps.executeBatch();⑶ 8ckcTNPu
conn.commit(); _6U=7<f
}catch(Exception e){ vP k\b 3E
e.printStackTrace(); {T;A50
} finally{ 5&Y%N(
try{ D,$!.5OA
if(ps!=null) { D1xIRyc/
ps.clearParameters(); k@}?!V*l
ps.close(); Evjvaa^
ps=null; |[6jf!F
} cXcrb4IKD
}catch(SQLException e){} pTzwyj!SD
DBUtils.closeConnection(conn); +=_^4
} TNi4H:\
} SynL%Y9)|,
public long getLast(){ w_gFN%8
return lastExecuteTime; +-%&,>R
} VIIBw
public void run(){ YgiLfz iT
long now = System.currentTimeMillis(); &\n<pXQ
if ((now - lastExecuteTime) > executeSep) { tr[(,kX
//System.out.print("lastExecuteTime:"+lastExecuteTime); mBAI";L3
//System.out.print(" now:"+now+"\n"); aL)}S%5o?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Kivr)cIG
lastExecuteTime=now; v@xbur\L
executeUpdate(); ^4G%*-
} Re[x$rw
else{ ]t2zwHo#
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); v d{`*|x
} [quT&E
} M53{e;.kN
} w(,K
//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 'R-Ly^:Qd
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类写好了,下面是在JSP中如下调用。 h4iz(*
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<% $Gy&
CountBean cb=new CountBean(); kzkrvC+u
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); lwVo%-
CountCache.add(cb); K3Sa6"U
out.print(CountCache.list.size()+"<br>"); S]"U(JmW\
CountControl c=new CountControl(); P0mY/bBU
c.run(); `/e
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out.print(CountCache.list.size()+"<br>"); c6 f=r
%>