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: jxiC
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CountBean.java lJ+0P2@h*
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/* 9k9_mjLZ
* CountData.java RZ6xdq}>
* 6Ztq
* Created on 2007年1月1日, 下午4:44 1h>yu3O
* 1?)Xp|O
* To change this template, choose Tools | Options and locate the template under bB
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* the Source Creation and Management node. Right-click the template and choose 'sLiu8G
* Open. You can then make changes to the template in the Source Editor. "+\ lws
*/ h tx;8:
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package com.tot.count; vgD {qg@
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/** D6CS8
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* hOFOO_byzO
* @author
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*/ eFBeJZuE|
public class CountBean { :`E8Z:-R
private String countType; $p#%G#T
int countId; kgy:Q'
/** Creates a new instance of CountData */ 4VHqBQ4
public CountBean() {} ;^La"m
public void setCountType(String countTypes){ xBUya4w
this.countType=countTypes; n"+[ :w4
} /R~1Zj2&
public void setCountId(int countIds){ *4U^0e
this.countId=countIds; Jo$G,Q
} IGS1|
public String getCountType(){ Dw=gs{8D
return countType; wUiys/OVM
} 3l[McZ
public int getCountId(){ ?notxE7 ]
return countId; :[\v
} %@;6^=
} d}LR l" _n
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CountCache.java 9Q(+ZG=JkV
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/* 7@Zx@
* CountCache.java b8$gx:aJ>$
* CSGz3uC2D
* Created on 2007年1月1日, 下午5:01 ^Y u6w\QM
* nt;haeJ
* To change this template, choose Tools | Options and locate the template under S{FROC~1R
* the Source Creation and Management node. Right-click the template and choose %YSpCI
* Open. You can then make changes to the template in the Source Editor. #Y0-BYa^
*/ %uJ<M-@r=u
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package com.tot.count; \%/#x V
import java.util.*; 0VckocF
/** pWPIJ>2G:
* A,V\"KU
* @author BYO"u6
*/ TpmwD{c[\
public class CountCache { $={:r/R`i
public static LinkedList list=new LinkedList(); T21ky>8E
/** Creates a new instance of CountCache */ e%4:)
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public CountCache() {} CNr/U*+
public static void add(CountBean cb){ vo\fUT@k
if(cb!=null){ 2-=\~<)
list.add(cb); j<2m,~k`V
} N2oRJ,:B
} {GKy'/[
} $&$w Y/F
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CountControl.java Ubh{!Y
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/* %FS$zOsgGK
* CountThread.java
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* N=5)fe%{4
* Created on 2007年1月1日, 下午4:57 hty0Rb[dH
* XYS'.6k(
* To change this template, choose Tools | Options and locate the template under aFe`_cnG
* the Source Creation and Management node. Right-click the template and choose {K4+6p
* Open. You can then make changes to the template in the Source Editor. JYrY[',u
*/ [q_`X~3
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package com.tot.count;
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import tot.db.DBUtils; ZA Jp%
import java.sql.*; masT>vM
/** k% sO 0
* is1' s[
* @author y"6y!
*/ }j2Y5
public class CountControl{ rC.eyq,105
private static long lastExecuteTime=0;//上次更新时间 <V7>?U l
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {NPuu?&
/** Creates a new instance of CountThread */ 1G0fp:\w
public CountControl() {} 7]x3!AlV
public synchronized void executeUpdate(){ %]gn?`O
Connection conn=null; Rw6;Z
PreparedStatement ps=null; ?gO8kPg/D
try{ za:a)U^n
conn = DBUtils.getConnection(); 'WI^nZM
conn.setAutoCommit(false); 2:BF[c`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 9Ro6fjjE
for(int i=0;i<CountCache.list.size();i++){ \k]x;S<a
CountBean cb=(CountBean)CountCache.list.getFirst(); B!dU>0&Ct
CountCache.list.removeFirst(); kloR#?8A
ps.setInt(1, cb.getCountId()); R*oXmuOsYA
ps.executeUpdate();⑴ V7Z4T6j4
//ps.addBatch();⑵ o]ag"Q
} uGwJK`!~
//int [] counts = ps.executeBatch();⑶ [6)UhS8
conn.commit(); KjFK/Og.
}catch(Exception e){ Ti2Ls5H}
e.printStackTrace(); bn(`O1r[(
} finally{ JXixYwm
try{ ~`GhS<D
if(ps!=null) { kdxz !
ps.clearParameters(); WYIQE$SEv
ps.close(); sK"9fU
ps=null; Dy]I8_
} -*~CV:2iq-
}catch(SQLException e){} N7b1.]<
DBUtils.closeConnection(conn); OdQT2PA_
} Qd_Y\PzS
} .MVY B\6Q0
public long getLast(){ 4EXB;[]
return lastExecuteTime; rUlS'L;$"
} Cv>o.Bp|
public void run(){ iweD
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long now = System.currentTimeMillis(); 'S<%Xm
if ((now - lastExecuteTime) > executeSep) { L>!8YUz7p$
//System.out.print("lastExecuteTime:"+lastExecuteTime); TDg@Tg0
//System.out.print(" now:"+now+"\n"); :qR=>n=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]Ni;w]KE
lastExecuteTime=now; `/"nTB
executeUpdate(); jYVE8Y)my
} iJv48#'ii
else{ (=16PYs
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); y8s!M
} [3W*9j
} ;uqx@sx ;
} `:wvh(
//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 f`8OM}un&
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类写好了,下面是在JSP中如下调用。 9Ew7A(BG_3
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<% SVa6V}"Iv
CountBean cb=new CountBean(); FZ|CqD"#
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); yoRU_%xA
CountCache.add(cb); Uu"0rUzt
out.print(CountCache.list.size()+"<br>"); QN>7~=`
CountControl c=new CountControl(); rVtw-[p
c.run(); @ct+7v~
out.print(CountCache.list.size()+"<br>"); .6m "'m0;
%>