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: X{cB%to
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CountBean.java e/g9r
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/* fI;nVRfp
* CountData.java 8SroA$^n
* "kcix!}&
* Created on 2007年1月1日, 下午4:44 $ZyOBxI
* ]Gm4gd`
* To change this template, choose Tools | Options and locate the template under <^>
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* the Source Creation and Management node. Right-click the template and choose ~5|R`%
* Open. You can then make changes to the template in the Source Editor. l=P)$O|=w
*/ VSUWX1k4%
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package com.tot.count; b(@GKH"W
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/** ^2BiMH3j
* Q$p3cepsK
* @author ;8MQ'#
*/ M*T!nwb
public class CountBean { :_HdOm
private String countType; au=@]n#<(
int countId; W^HE1Dt]
/** Creates a new instance of CountData */ a|y'-r90
public CountBean() {} 7fWZ/;p
public void setCountType(String countTypes){ 8H};pu2
this.countType=countTypes; |ul{d|
} % mPv1$FH
public void setCountId(int countIds){ fA1{-JzV<4
this.countId=countIds; VPO~veQ
} PQ_A^ 95
public String getCountType(){ M7Xn=jc
return countType; be-HF;lZe'
} zI^:{]p
public int getCountId(){ UT{`'#iT
return countId; Dby|l#X
} dlZ2iDQ%
} Ed0}$b
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CountCache.java j7I?K
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/* =s.0 f:(
* CountCache.java #$U/*~m $
* k&[6Ld0~56
* Created on 2007年1月1日, 下午5:01 W"\`UzOLQ
* 1)97AkN(O
* To change this template, choose Tools | Options and locate the template under a|]deJU^
* the Source Creation and Management node. Right-click the template and choose .*"KCQGOgM
* Open. You can then make changes to the template in the Source Editor. op-\|<i
*/ /ioBc}]
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package com.tot.count; A[fTpS ~~%
import java.util.*; 7zN7PHT=$t
/** NyC&j`d
* TntTR"6aD
* @author ZjY?T)WE9
*/ z^9rM"
public class CountCache { XLYGhM
public static LinkedList list=new LinkedList(); >ZgV8X:
/** Creates a new instance of CountCache */ X<W${L$G
public CountCache() {} b
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public static void add(CountBean cb){ V4Qy^nn1
if(cb!=null){ PD^ 6Ywn>s
list.add(cb); /={N^8^=x
} vqoK9
} 8ZjRMr}
} }{PG^ Fc<P
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CountControl.java G"L`9E<0V
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/* |eye) E:
* CountThread.java f*xv#G
* KT(v'KE 1
* Created on 2007年1月1日, 下午4:57 iN0'/)ar
* :T@} CJ
* To change this template, choose Tools | Options and locate the template under 'F/uD1;
* the Source Creation and Management node. Right-click the template and choose c%wztP;L
* Open. You can then make changes to the template in the Source Editor. jc!V|w^
*/ LV$Ko_9eA
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package com.tot.count; Ed-3-vJej6
import tot.db.DBUtils; g#1Y4
import java.sql.*; ]TtID4qL
/** Ms3GvPsgv
* s6}SdmE
* @author 211T}a
*/ {5ehm
public class CountControl{ Tk 'Pv
private static long lastExecuteTime=0;//上次更新时间 ;>5]KNj
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Bz%wV-
/** Creates a new instance of CountThread */ m9c`"!
public CountControl() {} $Dv5TUKw
public synchronized void executeUpdate(){ ^rY18?XC+:
Connection conn=null; OYmutq
PreparedStatement ps=null; ]w4?OK(j
try{ ^,f^YL;
conn = DBUtils.getConnection(); CZy3]O"qW
conn.setAutoCommit(false); g{>0Pa1?C
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .Tw:Y,G
for(int i=0;i<CountCache.list.size();i++){ WD kE
5
CountBean cb=(CountBean)CountCache.list.getFirst(); i>-#QKqJ
CountCache.list.removeFirst(); .>}Z3jUrf
ps.setInt(1, cb.getCountId()); #tw_`yh
ps.executeUpdate();⑴ bl10kI:F
//ps.addBatch();⑵ 8aM\B%NGWi
} p*1B*R
//int [] counts = ps.executeBatch();⑶ R S>qP;V*-
conn.commit(); sC2NFb-+&
}catch(Exception e){ Pv)^L
e.printStackTrace(); UbIUc}ge
} finally{ =jxy4`oF
try{ @li/Y6Wh
if(ps!=null) { R7h3O0@!
ps.clearParameters(); 0#m=76[b
ps.close(); NP4u/C<
ps=null; f1U8 b*F<
} v7hw% 9(=
}catch(SQLException e){} m9DTz$S.
DBUtils.closeConnection(conn); VT~%);.#
} dd
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} a>d`g
public long getLast(){ +`$$^x
return lastExecuteTime; ])?h~
} yVK l%GO
public void run(){ GlC (uhCpV
long now = System.currentTimeMillis(); *L Y6hph"
if ((now - lastExecuteTime) > executeSep) { 7j#Ix$Ur
//System.out.print("lastExecuteTime:"+lastExecuteTime); bkpN`+c
//System.out.print(" now:"+now+"\n"); <{YzmN\Z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 23'{{@30
lastExecuteTime=now; /Ah'KN|EN
executeUpdate(); %z.d;[Hs
} P)Oe?z;G?
else{ B"5xs
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); QOPh3+.5
} SL+n y(y
} p"H/N_b4
} <7L-25 =
//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 *.D{d0A
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类写好了,下面是在JSP中如下调用。 c@nh>G:y{&
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<% tehWGqx)
CountBean cb=new CountBean(); XJwgh y?(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t56PzT'M
CountCache.add(cb); ^Q+z^zlC
out.print(CountCache.list.size()+"<br>"); |942#rM
CountControl c=new CountControl(); 6g#E/{kQw
c.run(); zF? 6"
out.print(CountCache.list.size()+"<br>"); ~RBa&Y=Mb
%>