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: nb(#;3DQ
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CountBean.java %6kD^K-
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/* 6;[iX`LL
* CountData.java q+|Dm<Ug
* $?wX*
* Created on 2007年1月1日, 下午4:44 /HI#8
* (O/hu3
* To change this template, choose Tools | Options and locate the template under W53i5u(
* the Source Creation and Management node. Right-click the template and choose ^9qncvV
* Open. You can then make changes to the template in the Source Editor. vnXpC!1
*/ #H M0s~^w&
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package com.tot.count; u+XZdV
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/** /of,4aaK7
* +#'exgGU^[
* @author @qg=lt|(F
*/ )]X_')K
public class CountBean { V..m2nQj
private String countType; Q9FY.KUM
int countId; 1=W>zC
/** Creates a new instance of CountData */ :+!hR4Z~\;
public CountBean() {} 6D w[n
public void setCountType(String countTypes){ .VTHZvyn
this.countType=countTypes; *8X: fq
} 7NoB
public void setCountId(int countIds){ Ql
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this.countId=countIds; "sL#)<%
} YujhpJ<
public String getCountType(){ M6y:ze
return countType; !3?HpR/nV
} R &T(S
public int getCountId(){ 80axsU^H0
return countId; OC"W=[Myl
} S(9fGh
} Q]IpHNt[>
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CountCache.java gQ,PG
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/* LGRX@nF#
* CountCache.java FW=oP>f]w
* 8;Yx a8i e
* Created on 2007年1月1日, 下午5:01 +<8r?d2
* T4J(8!7
* To change this template, choose Tools | Options and locate the template under [fO \1J
* the Source Creation and Management node. Right-click the template and choose ~hYG%
* Open. You can then make changes to the template in the Source Editor. 5wiU4-{
*/ vKol@7%N
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package com.tot.count; N\<M4fn
import java.util.*; DoNbCVZ
/** v\0[B jhL?
* l9#M`x9
* @author |c dQJW
*/ Pou`PNvH
public class CountCache { rjx6Ad/\
public static LinkedList list=new LinkedList(); }\P9$D+
/** Creates a new instance of CountCache */ 4~DFtWbf
public CountCache() {} [p[Kpunr{l
public static void add(CountBean cb){ 56d,Sk)
if(cb!=null){ 0rjxWPc
list.add(cb); C!%BW%"R
} "4oY F:h
} ?psvhB{O
} :74)nbS
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CountControl.java yG2j!D
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/* F{ B__Kf
* CountThread.java O-}{%)[ F
* ~t.*B& A
* Created on 2007年1月1日, 下午4:57 ]k
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j
* !T#~.QP4
* To change this template, choose Tools | Options and locate the template under ,*}SfCon
* the Source Creation and Management node. Right-click the template and choose (7;}F~?h
* Open. You can then make changes to the template in the Source Editor. )&;?|X+p
*/ s(r(! FZ
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package com.tot.count; o!gl
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import tot.db.DBUtils; =K-B
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import java.sql.*; u-f_,],p
/** Fp'k{
* Gt2NUGU
* @author Qf6Vj,~N
*/ gle_~es'K
public class CountControl{ aS-rRL|\L
private static long lastExecuteTime=0;//上次更新时间 A8dIL5
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 R'u M7,7
/** Creates a new instance of CountThread */ q 6%jCt2'
public CountControl() {} D42Bm&JocO
public synchronized void executeUpdate(){ 0ua.aL'
Connection conn=null; zdlysr#
PreparedStatement ps=null; k8Qm +r<p
try{ {I&>`?7.
conn = DBUtils.getConnection(); @M?;~M?B]J
conn.setAutoCommit(false); 27<~m=`}d
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++){ p.SEW5
CountBean cb=(CountBean)CountCache.list.getFirst(); &S>m+m'
CountCache.list.removeFirst(); nX7{09
ps.setInt(1, cb.getCountId()); /608P:U
ps.executeUpdate();⑴ g0:mm,t\
//ps.addBatch();⑵ 2E9Cp
} W`*S?QGzl@
//int [] counts = ps.executeBatch();⑶ 4@&8jZ)a
conn.commit(); C{`+h163\
}catch(Exception e){ D'$ki[{,
e.printStackTrace(); &}_E~jKK
} finally{ }Dc0 Y
try{ WZOi,
if(ps!=null) { n,!PyJ
ps.clearParameters(); O-[ lL"T
ps.close(); k1e0kxn
ps=null; C!6?.\U/:c
} jQxv`H
}catch(SQLException e){} $b,o3eC
DBUtils.closeConnection(conn); 56Z 1jN^U
} Ikv@}^p 7
} OSY$qL2
public long getLast(){ />=)=CGv;
return lastExecuteTime; vq-Tq>
} 4E/Q+^?
public void run(){ q+<X*yC
long now = System.currentTimeMillis(); i0;
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if ((now - lastExecuteTime) > executeSep) { `O4Ysk72x9
//System.out.print("lastExecuteTime:"+lastExecuteTime); ZV=O oLt,
//System.out.print(" now:"+now+"\n"); 9#Gz2u $
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }SpjB
lastExecuteTime=now; G;#-CT
executeUpdate(); *{5p/}p
} lO&TSPD^
else{ `"`/_al^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); =aR'S\<
} AJ1(q:P
} <mN.6@*{
} `}<x"f7.z
//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 QT)D|]bH
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类写好了,下面是在JSP中如下调用。 GG@GjP<_
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<% [*^`rQ
CountBean cb=new CountBean(); "O@L
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); o,}`4_N||
CountCache.add(cb); ,v(K|P@
out.print(CountCache.list.size()+"<br>"); Awy-kou[C
CountControl c=new CountControl(); qYjR
c.run(); GF]V$5.ps
out.print(CountCache.list.size()+"<br>"); G>"=Af(t?Y
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