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: ('hT
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CountBean.java 3^wC<ZXcD
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/* >o/95xk2
* CountData.java `}fw1X5L
* VagT_D
* Created on 2007年1月1日, 下午4:44 zN!j%T.e
* BStk&b
* To change this template, choose Tools | Options and locate the template under rs]I
* the Source Creation and Management node. Right-click the template and choose Sh&PNJ-*
* Open. You can then make changes to the template in the Source Editor. aG{$Ic
*/ vzXag*0
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package com.tot.count; 3t"4TjAy
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/** O0huqF$K
* O{]9hm(tN
* @author <f>akT,W
*/ h<x4YB5Mj
public class CountBean { 80;n|nNB
private String countType; +Xy*?5E;C
int countId; PsnGXcj
/** Creates a new instance of CountData */ (=
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public CountBean() {} $,27pkwHeW
public void setCountType(String countTypes){ [6tSYUZs
this.countType=countTypes; 314=1JbL
} I#G0, &Gv
public void setCountId(int countIds){ Eu,`7iQ?(
this.countId=countIds; z|N3G E(.@
} %d;ezY '2
public String getCountType(){ Q(Gl{#b
return countType; v }\,o%t^
} X.FGBR7=q
public int getCountId(){ w>e
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return countId; GP a`e
} '@=PGpRF
} T!|=El>
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CountCache.java d~9!,6XM
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/* RU#F8O
* CountCache.java 1/Zh^foG
* I#rubAl
* Created on 2007年1月1日, 下午5:01 z#6?8y2-
* -{jdn%Y7CK
* To change this template, choose Tools | Options and locate the template under ytAWOt}`
* the Source Creation and Management node. Right-click the template and choose YY5!_k
* Open. You can then make changes to the template in the Source Editor. R 94^4I
*/
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package com.tot.count; &
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import java.util.*; #&
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/** h2Bz F
* 3V<&|
* @author L{fFC%|l2L
*/ ~O6\6$3b5E
public class CountCache { \jU |(DE
public static LinkedList list=new LinkedList(); O XP\R
/** Creates a new instance of CountCache */ I]`-|Q E
public CountCache() {} g(E"4M@t!
public static void add(CountBean cb){ 2kh"8oQ
if(cb!=null){ CH#k(sy
list.add(cb); PBjmGwg7
} S<wj*"|.s
} PoSpkJH
} \cJa;WM>
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CountControl.java gABr@>Vv
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/* sW@krBxMv
* CountThread.java na+d;h*~y
* F7*wQ{~
* Created on 2007年1月1日, 下午4:57 9&]M**X
* \wvg,j=
* To change this template, choose Tools | Options and locate the template under 0Q5^C!K
* the Source Creation and Management node. Right-click the template and choose U9hS<}<Ki
* Open. You can then make changes to the template in the Source Editor. ]/X(V|t
*/ ~FU@wV^
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package com.tot.count; 9ooY?J
import tot.db.DBUtils; IH*s8tPc
import java.sql.*; K4ZolWbU
/** &HZmQ>!R D
* :mcYZPX#
* @author zbkMFD.{y
*/ }f}}A=
public class CountControl{ <If35Z)~
private static long lastExecuteTime=0;//上次更新时间 }2 8=
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *Mc7f ?H
/** Creates a new instance of CountThread */ 5s{j=.O
public CountControl() {} yR5XJ;Tct
public synchronized void executeUpdate(){ ne}+E
Connection conn=null; r=.A'"Kf
PreparedStatement ps=null; J Yb}Zw;
try{ O[@q%&_
conn = DBUtils.getConnection(); i]{1^pKq
conn.setAutoCommit(false); 3>M&D20Z
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /b#l^x:j
for(int i=0;i<CountCache.list.size();i++){ >/$Fh:R-
CountBean cb=(CountBean)CountCache.list.getFirst();
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CountCache.list.removeFirst(); &EGqgNl
ps.setInt(1, cb.getCountId()); gY-5_Ab
ps.executeUpdate();⑴ 7r#ymQ
//ps.addBatch();⑵ \c,pEXG
} I{'f|+1
//int [] counts = ps.executeBatch();⑶ y]
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conn.commit(); ENVk{QE!
}catch(Exception e){ x3+oAb@o/
e.printStackTrace(); I?#85l{>
} finally{ l\0w;:N3
try{ &C<yfRDu
if(ps!=null) { )j l8!O7
ps.clearParameters(); >4` dy
ps.close(); SMr13%KN/
ps=null; @D^^_1~
} `O?T.p)
}catch(SQLException e){} K kW;-{c
DBUtils.closeConnection(conn); )::>q5c
} ;h=*!7:
} k*rZ*sSp
public long getLast(){ {PU!=IkTS
return lastExecuteTime; ]va>ex$d
} 8LkP)]4^sO
public void run(){ ~T7B$$
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { \2-@' ^i
//System.out.print("lastExecuteTime:"+lastExecuteTime); Xr63?N
//System.out.print(" now:"+now+"\n"); 3chPY4~A
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); lA(Q@yEW
lastExecuteTime=now; INs!Ame2
executeUpdate(); M,5j5<7
} g:l.MJT
else{ u9woEe?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +yob)%
} N{SQ(%V
} ^$>XW\yCs
} eK_*2=;XRW
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 bu7'oB~:V^
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类写好了,下面是在JSP中如下调用。 >Hb^P)3
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<% ]M>9ULQ
CountBean cb=new CountBean(); g>0XxjP4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); -{XRA6
CountCache.add(cb); tY${M^^<J
out.print(CountCache.list.size()+"<br>"); _mvxsG
CountControl c=new CountControl(); d,vNem-Z*L
c.run(); WW2Ob*
out.print(CountCache.list.size()+"<br>"); Jf)bHjC_V
%>