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: p|*b] 36
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CountBean.java HZ2 zL17
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/* v#IZSBvuQK
* CountData.java oU 8o;zk0
* HoM8V"8B
* Created on 2007年1月1日, 下午4:44 VxAR,a1+n
* JY>I
* To change this template, choose Tools | Options and locate the template under DNM~/Oo
* the Source Creation and Management node. Right-click the template and choose uoBPi[nK
* Open. You can then make changes to the template in the Source Editor. ,%m$_wA$
*/ eP3 itrH(
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package com.tot.count; 9Bmgz =8
}S&SL)
/** L/cbq*L
* %^E>~
* @author Fn%:0j
*/ Md m(xUs
public class CountBean { }@A~a`9g
private String countType; .~8IW,[
int countId; &9g#Vq%
/** Creates a new instance of CountData */ Vk~}^;`Y
public CountBean() {} G}~b
public void setCountType(String countTypes){ *JOv
this.countType=countTypes; q`;URkjk
} 4 ]8PF
public void setCountId(int countIds){ 1$2Rs-J
this.countId=countIds; CUw
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} 1r w>gR
public String getCountType(){ %s)E}cGH
return countType; ~GY;{
}
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public int getCountId(){ ^jhHaN]G^
return countId; 7y`~T+
} bmddh2
} CblL1 q8
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CountCache.java /3Gv51'
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/* )5V1HWjU
* CountCache.java ;j_#,Da9<
* %F/tbXy{
* Created on 2007年1月1日, 下午5:01 #6m//0 u
* y.eBFf
* To change this template, choose Tools | Options and locate the template under ;NPb
* the Source Creation and Management node. Right-click the template and choose %r,2ZLZ
* Open. You can then make changes to the template in the Source Editor. *'t`;m~
*/ }&naP
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package com.tot.count; &
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import java.util.*; K|1^?#n
/** p9sxA|O=y
* 4-n.4j|
* @author bKaV]Uy
*/ u})JQ<|
public class CountCache { \)"qN^we
public static LinkedList list=new LinkedList(); ?%0i,p@<
/** Creates a new instance of CountCache */ QY fS-
public CountCache() {} "7
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public static void add(CountBean cb){ ]V]o%onW
if(cb!=null){ ,^,J[F
list.add(cb); bU,&|K/
} LtvyWc`
} ) D`_V.,W
} |Z/ySAFM
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CountControl.java ?8nG F%p
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/* Ek.j@79
* CountThread.java Z,&ywMm/G
* Fu><lN7
* Created on 2007年1月1日, 下午4:57 4%{m7CK}
* \%VoX`B
* To change this template, choose Tools | Options and locate the template under g?+P&FL#I
* the Source Creation and Management node. Right-click the template and choose .lnD]Q
* Open. You can then make changes to the template in the Source Editor. O&0R ~<n
*/ [(K^x?\Y0'
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package com.tot.count; C|JWom\J
import tot.db.DBUtils; >) ^!gz8
import java.sql.*; Q'Tn+}B&
/** /][U$Q;Ke
* U\z+{]<<
* @author ?0<3"2Db~
*/
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public class CountControl{ >y@w-,1he
private static long lastExecuteTime=0;//上次更新时间 rYqvG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 33C#iR1(WJ
/** Creates a new instance of CountThread */ lqs_7HhvRS
public CountControl() {} ;Os3
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public synchronized void executeUpdate(){ +Snjb0
Connection conn=null; :4Vt
PreparedStatement ps=null; !14z4]b
try{ 0.5_,an3
conn = DBUtils.getConnection(); m4
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conn.setAutoCommit(false); (TQXG^n$gY
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 'mM5l*{
for(int i=0;i<CountCache.list.size();i++){ f<'C<xnf
CountBean cb=(CountBean)CountCache.list.getFirst(); G7<X l}
CountCache.list.removeFirst(); Tk:y>P!%a
ps.setInt(1, cb.getCountId()); .PxM
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ps.executeUpdate();⑴ %"6IAt
//ps.addBatch();⑵ NlMx!f>b%/
} o_5@R+&
//int [] counts = ps.executeBatch();⑶ s'^#[%EgB
conn.commit(); &Hqu`A/^
}catch(Exception e){ Lsz`nD5
e.printStackTrace(); a`uT'g[*
} finally{ 1,J.
try{ x@ O:
if(ps!=null) { wtKh8^:YD
ps.clearParameters(); (qrT0D6
ps.close(); 9+']`=a:
ps=null; z=U!D `]v
} }ie]7N6;
}catch(SQLException e){} )qIK7;
DBUtils.closeConnection(conn); hd B[H8Q
} #Grm-W9E
} ]gW J,
public long getLast(){ S7vE[VF5
return lastExecuteTime; @:@rks&
} `4qKQJw
public void run(){ yiq#p"Hs
long now = System.currentTimeMillis(); :KLD~k7yA(
if ((now - lastExecuteTime) > executeSep) { (r4\dp&
//System.out.print("lastExecuteTime:"+lastExecuteTime); dw|0K+-PH
//System.out.print(" now:"+now+"\n");
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;~J~g#
lastExecuteTime=now; _<7FR:oBZ
executeUpdate(); L9@jmh*E
} UK,P?_e
else{ K/-D 5U
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [1U_c*;i
} DvCt^O*
} /WfxI>v
} I'C,'
//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 86g+c
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类写好了,下面是在JSP中如下调用。 'Ap5Aq
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<% a5M>1&j/eC
CountBean cb=new CountBean(); <GN?J.B
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); De_</1Au!2
CountCache.add(cb); as4NvZ@+r
out.print(CountCache.list.size()+"<br>"); F?kVW[h?q
CountControl c=new CountControl(); w$4Lu"N:
c.run(); O|~'-^
out.print(CountCache.list.size()+"<br>"); xJhbGK
%>