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: f5*hOzKG6
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CountBean.java 7Y
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/* ;(Z9.
* CountData.java O}z-g&e.U
* AZ.
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* Created on 2007年1月1日, 下午4:44 F{eI[A
* VP }To
* To change this template, choose Tools | Options and locate the template under A ?[Wfq|
* the Source Creation and Management node. Right-click the template and choose MwD8a<2Dg
* Open. You can then make changes to the template in the Source Editor. LKM;T-
*/ >B$B|g~
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package com.tot.count; X(;WY^i!
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/** }4q1"iMlO
* N3\vd_D(
* @author T=[/x=
*/ u y13SkW
public class CountBean { U ?6.UtNf
private String countType; }Rq{9j,%
int countId; /kqa|=-`q
/** Creates a new instance of CountData */ xH>j
public CountBean() {} 4@9xq<<5
public void setCountType(String countTypes){ eY`o=xN
this.countType=countTypes; Hw,@oOh.
} l-8rCaq&J
public void setCountId(int countIds){ pE{Ecrc3|
this.countId=countIds; B#o6UO\
} $g
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public String getCountType(){ :;w#l"e7<
return countType; =DXN`]uN
} 4
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public int getCountId(){ qy/t<2'
return countId; Wfsd$kN6{
} |u#7@&N1
} Z)<lPg!YAR
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CountCache.java O&@CT] )8
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/* scy_
* CountCache.java CWSc #E
* UYhxgPGsj
* Created on 2007年1月1日, 下午5:01 ,Y7QmbX^
* 5jsZJpk$
* To change this template, choose Tools | Options and locate the template under wB"`lY
* the Source Creation and Management node. Right-click the template and choose C/q!!
* Open. You can then make changes to the template in the Source Editor. 3 ]pHc)p!.
*/ se29IhS!e
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package com.tot.count; pzeCdHF
import java.util.*; JD]uDuE
/** a" L9jrVrw
* sY&Z/Y
* @author G
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*/ 9<5S!?JL
public class CountCache { ~P'i
/*:
public static LinkedList list=new LinkedList(); eaDG7+iS
/** Creates a new instance of CountCache */ D=}\]Krmay
public CountCache() {} #j)"#1IE2W
public static void add(CountBean cb){ BCh|^Pk
if(cb!=null){ ">vi=Tr
list.add(cb); #GzowI'
} OU<v9`<
} dQy K4T
} aAgQ^LY
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CountControl.java '%y;{,g*
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/* gzN51B =D
* CountThread.java !i\ gCLg2_
* +tJ 7ZR%
* Created on 2007年1月1日, 下午4:57 WF<3
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* 22 feYm|
* To change this template, choose Tools | Options and locate the template under \q^:$iY~
* the Source Creation and Management node. Right-click the template and choose ;?%_jB$P
* Open. You can then make changes to the template in the Source Editor. 4B)%I`
*/ [OR"9W&
6 !wk5#
package com.tot.count; (QQkXlJ
import tot.db.DBUtils; 6i%Xf i
import java.sql.*; i ;^Ya
/** Pk;YM}
* od^ylg>K
* @author `i<Z<
<c>
*/ ?@;#|^k9
public class CountControl{ PJ^qE|X
private static long lastExecuteTime=0;//上次更新时间 J|`.d46
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 w8a49 Fv
/** Creates a new instance of CountThread */ wZWAx
public CountControl() {} ;RYIc0%
public synchronized void executeUpdate(){ DKF
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Connection conn=null; 5<YL^m{/L
PreparedStatement ps=null; tTWEhHQ`
try{ 'UM *7
conn = DBUtils.getConnection(); d{Owz&PL
conn.setAutoCommit(false); A#Y:VavQ?
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); OsKtxtLO
for(int i=0;i<CountCache.list.size();i++){ [pInF
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CountBean cb=(CountBean)CountCache.list.getFirst(); %*#+(A"V
CountCache.list.removeFirst(); `@#rAW D
ps.setInt(1, cb.getCountId()); ^9kx3Pw?8
ps.executeUpdate();⑴ nlA:C>=
//ps.addBatch();⑵ (p<pF].
} }b/P\1#z
//int [] counts = ps.executeBatch();⑶ Nnq1&j"m
conn.commit(); iUk#hLLC
}catch(Exception e){ zE~Xxp
e.printStackTrace(); o7@C$R_#
} finally{ zjOOEvi
try{ cQm4q19
if(ps!=null) { K~B
ps.clearParameters(); =}.gU WV
ps.close(); P>(FCX
ps=null; ;; ;=)'o
} n~.$iN
}catch(SQLException e){} GxEShSGOE
DBUtils.closeConnection(conn); wxYGr`f
} ZB`d&!W>
} 6@eF|GoP
public long getLast(){ :>U+HQll
return lastExecuteTime; E;[Uhh|78!
} dT[JVl+3=
public void run(){ pTXF^:8
long now = System.currentTimeMillis(); A0:rn\$l3
if ((now - lastExecuteTime) > executeSep) { W#=,FZT
//System.out.print("lastExecuteTime:"+lastExecuteTime); W1EYVXN
//System.out.print(" now:"+now+"\n"); N1B$z3E*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9Vo*AK'&U
lastExecuteTime=now; 8:>V'j
executeUpdate(); ZJ.an%4
} SMzq,?-`
else{ m xqY
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <'N:K@Cs
} </u=<^ire
} *QV"o{V
} ambr}+}
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 z+- o}i
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类写好了,下面是在JSP中如下调用。 %D5F7wB
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<% P-3f51 Q
CountBean cb=new CountBean(); =1@LMIi5x
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); EC 1|$Co
CountCache.add(cb); 6|~^P!&
out.print(CountCache.list.size()+"<br>"); 9\c]I0)3p
CountControl c=new CountControl(); : ^("L,AF
c.run(); ~?FhQd\Q
out.print(CountCache.list.size()+"<br>"); gn&Zt}@[
%>