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+v`
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CountBean.java Vl0Y'@{
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/* r,cK#!<%
* CountData.java R6qC0@*
* (V#*}eGy
* Created on 2007年1月1日, 下午4:44 g/`z.?
* 0{sYD*gK]
* To change this template, choose Tools | Options and locate the template under d?>pcT)G_
* the Source Creation and Management node. Right-click the template and choose I0(nRu<
* Open. You can then make changes to the template in the Source Editor.
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*/ y+P$}Nru
}!@X(S!do
package com.tot.count; ki9vJ<
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/** J|N>}di
* 1eMaKT_=
* @author 2hE+Om^n
*/ P*9L3R*=N
public class CountBean { f%c-
private String countType; & 6~AY:0r
int countId; S")*~)N@
/** Creates a new instance of CountData */ Oy~X@A
public CountBean() {} x<h-F
public void setCountType(String countTypes){ $iOkn|~<@W
this.countType=countTypes; * ;<>@*
} T``~YoIdz
public void setCountId(int countIds){ Fn*)!,)
this.countId=countIds; PZSi}j/
} 5vj tF4}7!
public String getCountType(){ xZp`Ke!
return countType; 7G9o%!D5
} o]m56
public int getCountId(){ BV6
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return countId; LKI2R_|n
} M;1B}x@
} Ub<^;Du5
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CountCache.java mKhlYVn
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/* 5.FAuzz
* CountCache.java E>w|i
* k{B;J\`E;
* Created on 2007年1月1日, 下午5:01 \>(S?)6
* $_b^p=
* To change this template, choose Tools | Options and locate the template under R9O[`~BA2
* the Source Creation and Management node. Right-click the template and choose j#JE4(&
* Open. You can then make changes to the template in the Source Editor. bAm ,gP
*/ `KzNBH,W
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package com.tot.count; TrmU
import java.util.*; +hKH\]
/** Y#aHGZ$i
* %!QY:[
* @author zwpgf
*/ |4A938'4j
public class CountCache { #\r5Q>
public static LinkedList list=new LinkedList(); 6qp'
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/** Creates a new instance of CountCache */ Hy0l"CA*|
public CountCache() {} \)mV2r!%
public static void add(CountBean cb){ FV W&)-I
if(cb!=null){ ^=gzms
list.add(cb); 6I,4 6 XZ-
} #ZvDf5A
} !BikqTM
} 2%zJI"Ic
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CountControl.java !$|h[ct
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/* NamO5(1C
* CountThread.java ]@bu%_s"
* ;H:+w\?8f$
* Created on 2007年1月1日, 下午4:57 VUE6M\&z>
* &fuJ%
* To change this template, choose Tools | Options and locate the template under yM-3nwk
* the Source Creation and Management node. Right-click the template and choose (S4[,Sx6E
* Open. You can then make changes to the template in the Source Editor. 5u3SP?.&
*/ _ZU.;0
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package com.tot.count; o$,Dh?l
import tot.db.DBUtils; #X?#v7i",D
import java.sql.*; bEc @"^)
/** y+.E}
* <.qhW^>X
* @author
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*/ w~I;4p~(N
public class CountControl{ iS%md
private static long lastExecuteTime=0;//上次更新时间 o#ajBOJ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 iYHCa }
/** Creates a new instance of CountThread */ jWL;ElM'
public CountControl() {} ]&l%L4Z
public synchronized void executeUpdate(){ ~GZpAPg*
Connection conn=null; 'HdOW[3o
PreparedStatement ps=null; ",&c"r4c
try{ Zc Y* TGx
conn = DBUtils.getConnection(); onOvE Y|R
conn.setAutoCommit(false); "Yu';&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {F~:86z(g
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); b=-LQkcZhK
CountCache.list.removeFirst(); Rw9 *!<Izt
ps.setInt(1, cb.getCountId()); |Q _]+[
ps.executeUpdate();⑴ =*Ad
//ps.addBatch();⑵ uI*2}Q
} 6q!smM
//int [] counts = ps.executeBatch();⑶ J6 VG j=/
conn.commit(); O]nZr
}catch(Exception e){ `p.O
e.printStackTrace(); IT~pp_6g
} finally{ )]?"H
try{ "ccP,#Y
if(ps!=null) { Vg+jF!\7
ps.clearParameters(); Xw2tCRzD
ps.close(); H!+T2<F9R
ps=null; Ef2#}%>
} GG@&jcp7
}catch(SQLException e){} NpIx\\d
DBUtils.closeConnection(conn); 8eVQnp*
} XtV=Gr8"
} 1ukCH\YgU
public long getLast(){ ]_ON\v1
return lastExecuteTime; Qs^RhF\d
} ;1&7v
public void run(){ 8+irul{H_
long now = System.currentTimeMillis(); A]FjV~PB
if ((now - lastExecuteTime) > executeSep) { B[I
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//System.out.print("lastExecuteTime:"+lastExecuteTime); ?l3PDorR
//System.out.print(" now:"+now+"\n"); >,v,4,c
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Cy~Pfty
lastExecuteTime=now; Ao:<aX,=
executeUpdate(); S1R:/9
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} jnl3P[uQ
else{ ;6?VkF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); AxOn~fZ!
} QE.a2
}
} zoU-*Rs6
} f[bx|6
//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 $g?`yE(K
v/Z!Wp1LV
类写好了,下面是在JSP中如下调用。 yE \dv)(<
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<% lAM"l)Ij
CountBean cb=new CountBean(); Of*z9YI
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^@&RJa-kb
CountCache.add(cb); BpGK`0H
out.print(CountCache.list.size()+"<br>"); UqP %S$9
CountControl c=new CountControl(); %e@Jc3
c.run(); !/6`<eQ
`
out.print(CountCache.list.size()+"<br>"); jNIZ!/K
%>