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: }tT"vCu
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CountBean.java "gXz{$q
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/* R_ojK&%
* CountData.java b>AFhj :
* KwOn<0P
* Created on 2007年1月1日, 下午4:44 dV<|ztv
* ;Y#~2eYCz
* To change this template, choose Tools | Options and locate the template under :e:jILQ[
* the Source Creation and Management node. Right-click the template and choose ~HsPYc8Fz
* Open. You can then make changes to the template in the Source Editor. .,[zI@9
*/ r#wMd9])
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package com.tot.count; l9XK;0R9
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/** E~xK1x"
* HONrt|c
* @author Y9ueE+6
*/ LD5n_W
public class CountBean { QD%~A0
private String countType; Pp1HOJYJp0
int countId; `<2y
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/** Creates a new instance of CountData */ Tm@d;O'E1
public CountBean() {} IB:Wh;_x
public void setCountType(String countTypes){ "; tl>Ot
this.countType=countTypes; > bWsUG9
} iIu
public void setCountId(int countIds){ MNO T<(
this.countId=countIds; ce&)djC7U
} Me[T=Tt`@w
public String getCountType(){
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return countType; C)/uX5
} K:fK!/
public int getCountId(){ 7f_4qb8
return countId; 8'?V5.6?|~
} W'6~`t
} e!b?SmNN
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CountCache.java *yOpMxE
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/* nC^?6il
* CountCache.java Ok[y3S
* GEXT8f(7
* Created on 2007年1月1日, 下午5:01 P9vN5|"M
* Z3Os9X9p
* To change this template, choose Tools | Options and locate the template under *xXa4HB
* the Source Creation and Management node. Right-click the template and choose mV0F^5
* Open. You can then make changes to the template in the Source Editor. nY"9"R\.=
*/ @47MJzC
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package com.tot.count; |&WeXVH E
import java.util.*; 7. 9n
/** ;|e {J$
* qYc]Y9fi
* @author jftoqK-
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*/ \k_0wt2x1
public class CountCache { :<4:h.gO8
public static LinkedList list=new LinkedList(); 5FcKY_
/** Creates a new instance of CountCache */ rVq=,>M9
public CountCache() {} aPaGnP:^
public static void add(CountBean cb){ 4A.ZMH
if(cb!=null){ C,+6g/{
list.add(cb); C"_f3[Z
} 8P.UB{QNe
} @$z/=g sy
} v;AMx-_WH
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CountControl.java kxp$Nnk
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/* 7F.t>$'
* CountThread.java q}*"0r
* !tBNA
* Created on 2007年1月1日, 下午4:57 /Za'L#=R
* 5fPYtVm
* To change this template, choose Tools | Options and locate the template under t=J\zyX!
* the Source Creation and Management node. Right-click the template and choose 2KMLpO&De
* Open. You can then make changes to the template in the Source Editor. /`#sp
*/ =XsdR?C
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package com.tot.count; EU.vw0}u8
import tot.db.DBUtils; 3Vj uk7
import java.sql.*; h[72iVn
/** }C.M4{a\
* W@v@|D@
* @author 8WK%g0gm
*/ WJCEiH
public class CountControl{ $Z(fPKRN/
private static long lastExecuteTime=0;//上次更新时间
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 bs$x%CR
/** Creates a new instance of CountThread */ jC>l<d_
public CountControl() {} rXXIpQRi$S
public synchronized void executeUpdate(){ L{(\k$>'
Connection conn=null; ^l;nBD#nJ
PreparedStatement ps=null; Z<6xQTx
try{ \^2%v~
conn = DBUtils.getConnection(); mz@`*^7?
conn.setAutoCommit(false); cMOvM0f
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); JCZ"#8M3
for(int i=0;i<CountCache.list.size();i++){ &x19]?D"+
CountBean cb=(CountBean)CountCache.list.getFirst(); /WXy!W30<
CountCache.list.removeFirst(); FU/yJy
ps.setInt(1, cb.getCountId()); ",	
ps.executeUpdate();⑴ d)`XG cx{=
//ps.addBatch();⑵ "H\'4'hg
} 0o2o]{rM{2
//int [] counts = ps.executeBatch();⑶ `'9Kj9}
conn.commit(); sL|lfc'bB
}catch(Exception e){ H S/1z
e.printStackTrace(); Tyt:Abym=
} finally{ g9(zJ
try{ 4Z>hP]7
if(ps!=null) { t]LCe\#
ps.clearParameters(); Z)Y--`*
ps.close(); *F/ uAI^)
ps=null; c(Zar&z,E
} 0:UK)t)3I
}catch(SQLException e){} c n#JO^8
DBUtils.closeConnection(conn); 'bp*hqG[
} xxOo8+kA
} HVaWv ].
public long getLast(){ 9k =-8@G9
return lastExecuteTime; ^~}|X%q3
} WLGx=
;
public void run(){ .CH0PK=l
long now = System.currentTimeMillis(); 9{@ #tx
if ((now - lastExecuteTime) > executeSep) { ;m$F~!Y
//System.out.print("lastExecuteTime:"+lastExecuteTime); =t1.j=oC
//System.out.print(" now:"+now+"\n"); 4K` N3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3)v6N_
lastExecuteTime=now; ;Vc@]6Ck
executeUpdate(); S@]7
} u38FY@U$
else{ JmdXh/X
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (x,w/1
} d&'z0]mOe
} eA9U|&o
} <Ur(< WTV
//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 fo~8W`H&
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类写好了,下面是在JSP中如下调用。 'SF+P)Kmz
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<% FSv')`}
CountBean cb=new CountBean(); a6=mE?JTB
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Vr/UbgucJ
CountCache.add(cb); /=Bz[O
out.print(CountCache.list.size()+"<br>"); <y5V],-U
CountControl c=new CountControl(); mMmzi4HL
c.run(); iJ_`ZM.w
out.print(CountCache.list.size()+"<br>"); (;YO]U4
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