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: G#n27y nh
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CountBean.java h6la+l?x
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/* -F@Rpfrj_#
* CountData.java /]iv9e{uh(
* Rq9v+Xq2
* Created on 2007年1月1日, 下午4:44 UiF ?Nx~
* nv@$'uQRp
* To change this template, choose Tools | Options and locate the template under RLecKw&1{3
* the Source Creation and Management node. Right-click the template and choose VA.:'yQtJ
* Open. You can then make changes to the template in the Source Editor. El]Rrku
*/ j$Gb>Ex>
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package com.tot.count; VO[s:e9L
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/** qdNYY&6>?u
* 'Pr(7^
* @author _T8#36iR
*/ Gl`Yyw@84
public class CountBean { 'mG[#M/Y
private String countType; )\'U$
int countId; [ gx<7}[
/** Creates a new instance of CountData */ >*{\N^:z
public CountBean() {} fg+Q7'*Vq
public void setCountType(String countTypes){ Z!7#"wO9+V
this.countType=countTypes; 8H3|^J
} :Uj+iYE8Z8
public void setCountId(int countIds){ Ah)_mxK
this.countId=countIds; .B_)w:oF
} 3($%A GKJ
public String getCountType(){ :Y~fPke
return countType; IHMZE42
} Z/6B[,V
public int getCountId(){ )r5QOa/
return countId; ]X;Ty\UD&
} _U%!&_m6
} >jRz4%
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CountCache.java pZ%/;sxYa
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/* ~'=s?\I
* CountCache.java ko$bCG%
* 9bq#&~+
* Created on 2007年1月1日, 下午5:01 !+=jD3HTJ
* ?4(uwXp
* To change this template, choose Tools | Options and locate the template under a[[u>oHyd
* the Source Creation and Management node. Right-click the template and choose j*rra
* Open. You can then make changes to the template in the Source Editor. UYD(++
*/ %'%r.
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package com.tot.count; `lqMifD
import java.util.*; <s)+V6\E
/** FsTE.PT
* qun#z$
* @author $xa#+
*/ 7V%}U5
public class CountCache { CKmoC0.
public static LinkedList list=new LinkedList(); MjQKcL4%7
/** Creates a new instance of CountCache */ I[WW1P5
public CountCache() {} p
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public static void add(CountBean cb){ /{\tkvv-Z
if(cb!=null){ >A7),6
list.add(cb); a>(LFpVk}
} }<9*eAn`
} t8E'd:pE
} 6 80i?=z
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CountControl.java n$F&gx'^
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/* \[%[`m
* CountThread.java /}]X3ng
* YFy5>*W
* Created on 2007年1月1日, 下午4:57 3)Wi?
-
* 7-nwfp&|$
* To change this template, choose Tools | Options and locate the template under ,H'O`oV!1E
* the Source Creation and Management node. Right-click the template and choose & 2& K9R
* Open. You can then make changes to the template in the Source Editor. o{(-jhR
*/ Z; r}Gm
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package com.tot.count; qXn%c"
import tot.db.DBUtils; M%/ML=eLi
import java.sql.*; /<\>j+SC
/** w*e O9k
* 66,?f<b
* @author s>9w+|6Ji
*/ ]<WKi=
public class CountControl{ XuVbi=pN.2
private static long lastExecuteTime=0;//上次更新时间 %($sj|_l
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 hIuKs5`
/** Creates a new instance of CountThread */ H
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public CountControl() {} h?p&9[e`
public synchronized void executeUpdate(){ @D[jUC$E
Connection conn=null; t.v@\[{-
PreparedStatement ps=null; S6*3."Sk
try{ W1w)SS
conn = DBUtils.getConnection(); 24}r;=U
conn.setAutoCommit(false); gxycw4kz
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Sx5r u?$.
for(int i=0;i<CountCache.list.size();i++){ wv #1s3
CountBean cb=(CountBean)CountCache.list.getFirst(); ]/XNfb
CountCache.list.removeFirst(); ^D/:[
ps.setInt(1, cb.getCountId()); MW &iNioX
ps.executeUpdate();⑴ Q4JwX=ZVj
//ps.addBatch();⑵ 5#p [Q _
} Qb!9QlW
//int [] counts = ps.executeBatch();⑶ C%85Aq* 4
conn.commit(); T+8F'9i`
}catch(Exception e){ ?dVF@
e.printStackTrace(); T_lexX[\
} finally{ (x2I*<7P
try{ 5 S$*YRp
if(ps!=null) { 4(B{-cK
ps.clearParameters(); Z,.*!S=?h
ps.close(); N1jj\.nB
ps=null; %u-l6<w#R
} BI?M/pIm
}catch(SQLException e){} g<-x"$(C&
DBUtils.closeConnection(conn); f>g>7OsD]
} B5hk]=Ud
} iEux`CcJ.
public long getLast(){ =5a~xlBjD
return lastExecuteTime; Q+*o-
} {0WLY@7 2?
public void run(){ L5Rj;qhi
long now = System.currentTimeMillis(); j)?I]j/
if ((now - lastExecuteTime) > executeSep) { iqig~fjK~
//System.out.print("lastExecuteTime:"+lastExecuteTime); U{gJn#e/.
//System.out.print(" now:"+now+"\n"); ]7}2"?J4v
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]xBQ7Xqf|
lastExecuteTime=now; ^EdY:6NJ=A
executeUpdate(); pP;GDW4
} D:sQHJ.y
else{ v4kk4}lE
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); r3<yG"J86
} *IJctYJaX
} <\|f;7/
} Z#IRNFj
//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 8
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类写好了,下面是在JSP中如下调用。 s
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<% ;]34l."85
CountBean cb=new CountBean(); m;)[gF
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $/ew'h9q
CountCache.add(cb); qP-*
out.print(CountCache.list.size()+"<br>"); EtK,C~C}8
CountControl c=new CountControl(); LSv0zAIe/
c.run(); j
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out.print(CountCache.list.size()+"<br>"); I:Wrwd
%>