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: K5P Gi#
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CountBean.java /0Z|+L9Jo
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/* 5){tBK|
* CountData.java zx
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* +2-
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* Created on 2007年1月1日, 下午4:44 6kP7
* &foD&
* To change this template, choose Tools | Options and locate the template under MinbE13?U
* the Source Creation and Management node. Right-click the template and choose IeO-O'^&`
* Open. You can then make changes to the template in the Source Editor. 6a7vlo
*/ [m~b[ZwES
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package com.tot.count; {d| |q<.-
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/** LEWa6'0rq
* r])Z9bbi
* @author AnRlH
*/ _o\>V:IZ
public class CountBean { - o4@#p> >
private String countType; \^Ep>Pq`]
int countId; 7 n\mj\
/** Creates a new instance of CountData */ $2Ka u 1
public CountBean() {}
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public void setCountType(String countTypes){ PoJmW^:}
this.countType=countTypes; -UJ?L
} 3voW
public void setCountId(int countIds){ aD+0\I[x
this.countId=countIds; z9^c]U U)E
} ~D*b3K8X
public String getCountType(){ <'W=]IAV
return countType; ldK>HxM%Z
} f(!E!\&n^
public int getCountId(){ &j3`
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return countId; GaHA%
} Ft3I>=f{
} BlL|s=dlQV
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CountCache.java HC?0Lj
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/* /CH(!\bQ
* CountCache.java 7LG+$LEz
* %Nl`~Kz9U
* Created on 2007年1月1日, 下午5:01 oL#xDG
* +a #lofhv
* To change this template, choose Tools | Options and locate the template under Gv;;!sZ
* the Source Creation and Management node. Right-click the template and choose jH(&oV
* Open. You can then make changes to the template in the Source Editor. JwjI{,jY
*/ A1Ka(3"
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package com.tot.count; ]\7lbLv
import java.util.*; 9MT? .q
/** JfbKf~g
* s\_l=v3
* @author `{DG;J03[
*/ 6nc0=~='$
public class CountCache { FW_G\W.
public static LinkedList list=new LinkedList(); <8f(eP\*F
/** Creates a new instance of CountCache */ u %'y_C3
public CountCache() {} U7E
public static void add(CountBean cb){ '5AvT:
^u
if(cb!=null){ .?B{GnB>
list.add(cb); )AJ=an||5
} TiQ^}5~M
} lw s(/a*c
} {$0&R$v3
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CountControl.java `%oIRuYG]j
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/* mGO>""<:
* CountThread.java
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* xHHV=M2l(s
* Created on 2007年1月1日, 下午4:57 V`[P4k+b
* |gW
* To change this template, choose Tools | Options and locate the template under 3524m#4&@
* the Source Creation and Management node. Right-click the template and choose Qo.Uqz.C
* Open. You can then make changes to the template in the Source Editor. alc]
*/ +ZclGchw
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package com.tot.count; b_|u<
import tot.db.DBUtils; ;Xyte
import java.sql.*; BB63xEx
/** Z2#`}GI_m
* IfMpY;ow=
* @author +1/b^Ac
*/ +qhnP$vIe
public class CountControl{ JD ]OIh
private static long lastExecuteTime=0;//上次更新时间 1Fs-0)s8
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 i|S:s
/** Creates a new instance of CountThread */ p0Gk j-
public CountControl() {} &L%Jy #=
public synchronized void executeUpdate(){ PyFj@n
Connection conn=null; srK53vKMHW
PreparedStatement ps=null; =-Nsc1&
try{ ;\x~ '@
conn = DBUtils.getConnection(); HxZ.OZbR
conn.setAutoCommit(false); ;SKcbws
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); LQqfi
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for(int i=0;i<CountCache.list.size();i++){ q? 9GrwL8F
CountBean cb=(CountBean)CountCache.list.getFirst(); ]IS;\~
CountCache.list.removeFirst(); iX%n0i
ps.setInt(1, cb.getCountId()); > ws!5q
ps.executeUpdate();⑴ @cIgxp
//ps.addBatch();⑵ j=9ze op
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} 2d 8=h6
//int [] counts = ps.executeBatch();⑶ 6{.J:S9n
conn.commit(); pv&^D,H,
}catch(Exception e){ _f|/*.
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e.printStackTrace(); (ND%}
} finally{ Z(;AyTXA
try{ HxIoA
if(ps!=null) { P6YQK+
ps.clearParameters(); s"coQ!e1.
ps.close(); \(fq8AL?
ps=null; TF\sP8>V
} Xpl?g=B&u
}catch(SQLException e){} 88 l,&2q
DBUtils.closeConnection(conn); n P1GW6Pu
} 8_a3'o%5
} `%=<R-/#7S
public long getLast(){ iP#=:HZu;
return lastExecuteTime; aMJ;bQD
} W#{la`#Bu
public void run(){ h/K@IAd
long now = System.currentTimeMillis(); .$0Pr%0pWI
if ((now - lastExecuteTime) > executeSep) { #9:2s$O[x
//System.out.print("lastExecuteTime:"+lastExecuteTime); bi$VAYn.^
//System.out.print(" now:"+now+"\n"); mxp Y&Y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); yFjVKp'P
lastExecuteTime=now; |dk[cX>
executeUpdate(); 8W -@N
} H^
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else{ xA #H0?a]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); k':s =IXW
} >f$NzJ}
} vq>l>as9O
} b\giJ1NJB
//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=M!e<'
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类写好了,下面是在JSP中如下调用。 "!KpXBc,>
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<% 3m=2x5{L
CountBean cb=new CountBean(); LT_iS^&1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *_"u)<J
CountCache.add(cb); 3sbK7,4
out.print(CountCache.list.size()+"<br>"); {G*OR,HN
CountControl c=new CountControl(); d!V$Y}n
c.run(); j?-R]^-5
out.print(CountCache.list.size()+"<br>"); 7&+Ys
%>