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: 11T\2&Q
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CountBean.java xwxj j
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/* D5b_m|7%
* CountData.java c]r|I%D
* NKKOA
* Created on 2007年1月1日, 下午4:44 ?t42=nvf
* UhTr<(@
* To change this template, choose Tools | Options and locate the template under kf!/9
* the Source Creation and Management node. Right-click the template and choose ?KXQ)Y/su
* Open. You can then make changes to the template in the Source Editor. x=#5\t9
*/ .8!0b iS
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package com.tot.count; |Z^g\l.j{
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/** q$rA-`jw
* vUs7#*
* @author 'uzv\[
*/ ^z;,deoGh
public class CountBean { tuUXW5!/
private String countType; o#) !b:/
int countId; BZc-
/** Creates a new instance of CountData */ <xjv7`G7
public CountBean() {} xm0#4GFUS
public void setCountType(String countTypes){ J-<B*ot+lX
this.countType=countTypes; B[B<U~I}
} kw:D~E(
public void setCountId(int countIds){ j/pQSlV
this.countId=countIds; Le
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} ee^_Dh4
public String getCountType(){ MEnHC'nI
return countType; JwtI(>cI
} Q3q.*(#
public int getCountId(){ I=yj
return countId; 3F} KrG
} 5yiiPK$qr
} E}vO*ZZEw
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CountCache.java m
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/* 5l/l]
* CountCache.java <^_Vl8%
* HHTsHb{7
* Created on 2007年1月1日, 下午5:01 2\\3<
* Su$ 1 t
* To change this template, choose Tools | Options and locate the template under [(F<|f:n
* the Source Creation and Management node. Right-click the template and choose dd7nO
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* Open. You can then make changes to the template in the Source Editor. F'$S!K58
*/ $jh>zf
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package com.tot.count; EJ ~kZ3
import java.util.*; Q9xx/tUW
/** )$h9Y
* XJ~l5}y ]
* @author 3t{leuO'
*/ lO:{tV
public class CountCache { &N_c-@2O
public static LinkedList list=new LinkedList(); 7QiCZcb\
/** Creates a new instance of CountCache */ xyjVdD\
public CountCache() {} nCMa$+
public static void add(CountBean cb){ kz;_f
if(cb!=null){ A=C3e4.C
list.add(cb); wy-
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} qZsddll
} ~)a;59<$
} G0
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CountControl.java `h9)`*
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/* 2C]la
* CountThread.java %SO%{.}Zf
* SKpPR;=q|:
* Created on 2007年1月1日, 下午4:57 $dp#nyP
* 7(~H77
* To change this template, choose Tools | Options and locate the template under kTZx-7~
* the Source Creation and Management node. Right-click the template and choose U%t/wq
* Open. You can then make changes to the template in the Source Editor. km\ld&d]$
*/ .e2A*9,
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package com.tot.count; :-\ yy
import tot.db.DBUtils; %^5 @z1d,
import java.sql.*; ?6iatI !
/** n?LIphc\
* 0 {JK4]C
* @author Kxl,]
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*/ 7Fi2^DlgX
public class CountControl{ Pb8Z))9j
private static long lastExecuteTime=0;//上次更新时间 2vkB<[tSs
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >6I.%!jU
/** Creates a new instance of CountThread */ !UMo4}Y
public CountControl() {} aR)en{W
public synchronized void executeUpdate(){ V9E6W*IE
Connection conn=null; H[7cA9FI
PreparedStatement ps=null; x:?a;m uf
try{ oCKM5AVWsv
conn = DBUtils.getConnection(); Hg9.<|+yo
conn.setAutoCommit(false); <@e+-$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); |[37:m
for(int i=0;i<CountCache.list.size();i++){ /Fo/_=FE 2
CountBean cb=(CountBean)CountCache.list.getFirst(); C. Ja;RFq
CountCache.list.removeFirst();
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ps.setInt(1, cb.getCountId()); 2yQ}Lxr(
ps.executeUpdate();⑴ XJh:U0
//ps.addBatch();⑵ 7ZL#f![{
} IjDT'p_
//int [] counts = ps.executeBatch();⑶ crNjI`%tw
conn.commit(); `N,Vs n"
}catch(Exception e){ 5{ FM#@
e.printStackTrace(); Ybt_?Q9#]
} finally{ ?ng14e
try{ <m>l-]
if(ps!=null) { PNJe&q0*
ps.clearParameters(); M[K0t>ih
ps.close(); ;>Ca(Y2M
ps=null; /iUUM
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} P YF.#@":&
}catch(SQLException e){} \|~?x#aA
DBUtils.closeConnection(conn); !FB \h<6
} %Nm @f'
} q qe2,X?
public long getLast(){ o3F|#op
return lastExecuteTime; !)%>AH'
} d=?Mj]
public void run(){ 3Rd`Ysp
long now = System.currentTimeMillis(); Jh\:X<q
if ((now - lastExecuteTime) > executeSep) { j6e}7
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7rdw`
//System.out.print(" now:"+now+"\n"); ^S#\O>GHP
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ("?&p3];b
lastExecuteTime=now; NuD[-;N]
executeUpdate(); |)-|2cPRur
} }. xrJ52Tz
else{ B.YMP;7>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ;vJ\]T ml
} 2Io6s'
} Ns2,hQFc
} m4"N+_j
//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 3ximNQ}S
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类写好了,下面是在JSP中如下调用。 ut$,?k!M
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<% Uvh~B^6
CountBean cb=new CountBean(); 7$ =Y\P
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); BIV<ti$.
CountCache.add(cb); Y$`eg|$
out.print(CountCache.list.size()+"<br>"); I7fb}j`/
CountControl c=new CountControl(); *#1y6^
c.run(); rBD(2M
out.print(CountCache.list.size()+"<br>"); 2$
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