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: $=>:pQbBVX
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CountBean.java Bk.`G)t
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/* [Z'4YXS
* CountData.java OmK0-fa/
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* Created on 2007年1月1日, 下午4:44 S=<
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* c\P}ZQ
* To change this template, choose Tools | Options and locate the template under lr)MySsu#H
* the Source Creation and Management node. Right-click the template and choose Cu$`-b^y
* Open. You can then make changes to the template in the Source Editor. /Yww G;1
*/ )i39'0a
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package com.tot.count; T3)m{gv0`
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/** ;F, 6]LH!
* W^:g_
* @author RC"xnnIJv
*/ D 5Z7?Y
public class CountBean {
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private String countType; ^CDh! )
int countId; odcrP\S
/** Creates a new instance of CountData */ ]%Whtj.,x7
public CountBean() {} _#P5j#
public void setCountType(String countTypes){ ER]C;DYX
this.countType=countTypes; z"sv,W
} OnW,R3eg
public void setCountId(int countIds){ 5=MM^$QG
this.countId=countIds; kP~ ;dJD
} 5FNf)F
public String getCountType(){ Zr\G=0`
return countType; !G~\9
} t&bE/i_T
public int getCountId(){ =U~\iJ
return countId; 5i3nz=~o
} ybm&g( -\
} ORV'dr
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CountCache.java ==7=1QfP
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/* l>>,~
* CountCache.java U
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* oxqD/fY
* Created on 2007年1月1日, 下午5:01 .3,Ow(3l
* 0.t1p(x;
* To change this template, choose Tools | Options and locate the template under Zo(QU5m0
* the Source Creation and Management node. Right-click the template and choose o{QPW
* Open. You can then make changes to the template in the Source Editor. G|]39/OO3{
*/ ]
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package com.tot.count; nxYp9,c"
import java.util.*; p>]2o\["
/**
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* Os7 3u#!'
* @author HV6'0_R0
*/ ViT$]Nv
public class CountCache { -@_V|C'?
public static LinkedList list=new LinkedList(); #
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/** Creates a new instance of CountCache */ ?_c*(2i&^
public CountCache() {} Q|}Pc>ae
public static void add(CountBean cb){ ~v<,6BS<$Z
if(cb!=null){ 5zBsu lRt
list.add(cb); Z66@@?`
} 3F0:v,+;
} mM7S9^<UH
} _7zER6#}
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CountControl.java 6,|)%~VUm
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/* VXAgp6
* CountThread.java L~jKx)S%
* l0$
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* Created on 2007年1月1日, 下午4:57 uU]4)Hp
* ^CwzAB
* To change this template, choose Tools | Options and locate the template under 6!n%SUt
* the Source Creation and Management node. Right-click the template and choose DjjG?(1
* Open. You can then make changes to the template in the Source Editor. x+9aTsZ
*/ nNFZ77lg
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package com.tot.count; ` 0k
import tot.db.DBUtils; `?VB)
import java.sql.*; F+S;u=CKx
/** NY
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* J,E'F!{
* @author T(^<sjOs
*/ E0}jEl/{
public class CountControl{ PU^Z7T);
private static long lastExecuteTime=0;//上次更新时间 *r+i=i8{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 X] /r'Tz
/** Creates a new instance of CountThread */ yl%F}kBR
public CountControl() {} @&]j[if(s
public synchronized void executeUpdate(){ tsZrn
Connection conn=null; :r[`bqC;\*
PreparedStatement ps=null; zTP3JOe(
try{ y@G5I>v
conn = DBUtils.getConnection(); C``%<)WC
conn.setAutoCommit(false); AtA}OY]D/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !G#3jh:kiY
for(int i=0;i<CountCache.list.size();i++){ vpUS(ztvs
CountBean cb=(CountBean)CountCache.list.getFirst(); s"G6aM
CountCache.list.removeFirst(); Au"[2cG
ps.setInt(1, cb.getCountId()); X.g")Bt7
ps.executeUpdate();⑴ l\*}
//ps.addBatch();⑵ Db=
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} 2|#3rF
//int [] counts = ps.executeBatch();⑶ 59p'Ega.
conn.commit(); BjJ$I^
}catch(Exception e){ ])a?ri
e.printStackTrace(); ;/SM^&Y
} finally{ o;\0xuM@
try{ >0SF79-RE
if(ps!=null) { &S<tX]v
ps.clearParameters(); HlY4%M5q/
ps.close(); ^[8e|,U
ps=null; ,l`q
} C 9,p-
}catch(SQLException e){} 6lq7zi}'w
DBUtils.closeConnection(conn); l<{]%=Qg
} $d!Sl
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} U^~K-!0
public long getLast(){ =[?2'riI
return lastExecuteTime; ALwkX"AN
} 2:/'
public void run(){ %dS7u$Rnh
long now = System.currentTimeMillis(); }jfU qqFd
if ((now - lastExecuteTime) > executeSep) { n\.K:t[:
//System.out.print("lastExecuteTime:"+lastExecuteTime); <0 R7uH
//System.out.print(" now:"+now+"\n"); iH(
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r&xqsZ%R
lastExecuteTime=now; _d]w)YMO
executeUpdate(); )"jG)c^1*
} <i~ (
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else{ 1U~AupHE
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); o~gduNG#
} ^QB/{9 #
} i,S%:0c7)
} #:vos VqG
//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 X!CLOHVAa
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类写好了,下面是在JSP中如下调用。 Yiu)0\ o
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<% 2ADUJ
CountBean cb=new CountBean(); x7l)i!/$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); TpZ) wC
CountCache.add(cb); ?;|$R
out.print(CountCache.list.size()+"<br>"); 3oxQ[.o
CountControl c=new CountControl(); h^~eTi;c]Q
c.run(); %6L!JN
out.print(CountCache.list.size()+"<br>"); '7wI 2D
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