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: 7}e73
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CountBean.java 3ud_d>
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/* $kef_*BQg
* CountData.java oMV<Yn_<
* /G h?z
* Created on 2007年1月1日, 下午4:44 /
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* Th6xwMq
* To change this template, choose Tools | Options and locate the template under 3B5GsI
* the Source Creation and Management node. Right-click the template and choose OWRT6R4v
* Open. You can then make changes to the template in the Source Editor. G&HCOR!h
*/ aqk0+
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package com.tot.count; a.yCd/
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/** TxD,A0
* r#%z1u
* @author Xo:!U=m/#
*/ vP{22P
public class CountBean { [Q2"OG@Q
private String countType; E9IU,P6a
int countId; >qBQfz:U>
/** Creates a new instance of CountData */ hY@rt,! 8
public CountBean() {} j:;[Y `2
public void setCountType(String countTypes){ :"9P {xe^
this.countType=countTypes; $R2iSu{kO
} W5^m[,GU'
public void setCountId(int countIds){ w+NdEE4H9z
this.countId=countIds; Pn*+g!`
} ROyG+dUy
public String getCountType(){ V_T.#"C4=z
return countType; n@)Kf
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} ~<?+(V^D
public int getCountId(){ n5~7x
return countId; ^T#bla893
} $-}a<UFE;
} .m]"lH*
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CountCache.java <B?@,S>
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/* a$*)d($
* CountCache.java oXef<- :
* Wz~=JvRHh
* Created on 2007年1月1日, 下午5:01 s?8vs%(l
* .I"Qu:``
* To change this template, choose Tools | Options and locate the template under W'BB FG
* the Source Creation and Management node. Right-click the template and choose .m&JRzzV
* Open. You can then make changes to the template in the Source Editor. *t JgQ[
*/ gua +-##)
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package com.tot.count; 2L<iIBSJwm
import java.util.*; Be=J*D!E=>
/** H<|ilL'fX
* O#,Uz2
* @author GxL;@%B
*/ R; wq
public class CountCache { qW1d;pt
public static LinkedList list=new LinkedList(); pu:Ie#xTDf
/** Creates a new instance of CountCache */ jo8hVWJ7V*
public CountCache() {} 0@K?'6
public static void add(CountBean cb){ K/,y"DUN&
if(cb!=null){ =r3 %jWH6
list.add(cb); O]\6Pv@N
} E,S[3 +
} 6V"|
} 3++}4%w
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CountControl.java Ua>lf8w<
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/* Nq`@ >Ml
* CountThread.java eD4qh4|u.
* (h}5*u%h
* Created on 2007年1月1日, 下午4:57 G234UjN%
* M7O5uW`
* To change this template, choose Tools | Options and locate the template under IMKyFp]h-
* the Source Creation and Management node. Right-click the template and choose xpJ6M<O{8
* Open. You can then make changes to the template in the Source Editor. ZPktZ
*/ 6`>WO_<z
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package com.tot.count; E<j}"W$a
import tot.db.DBUtils; $)1i)/]9U
import java.sql.*; pSjJ u D
/** 0]3 ,0s $}
* hV(>}hb
* @author WF)(Q~op0U
*/ G E=J Y
public class CountControl{ yqaLqZ$
private static long lastExecuteTime=0;//上次更新时间 l EcZ/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 JnWG_|m)
/** Creates a new instance of CountThread */ 1S&GhJ<wJ
public CountControl() {} #H'j;=]:
public synchronized void executeUpdate(){ 81gcM?
Connection conn=null; O_zW/#
PreparedStatement ps=null; LW={| 3}
try{ vD=>AAvG
conn = DBUtils.getConnection(); mv5=>Xc6
conn.setAutoCommit(false); +VJS/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ! :[`>=!
for(int i=0;i<CountCache.list.size();i++){ #Tz$ona
CountBean cb=(CountBean)CountCache.list.getFirst(); a.n;ika]-
CountCache.list.removeFirst(); FeW}tKH
ps.setInt(1, cb.getCountId()); @%(Vi!Cv"R
ps.executeUpdate();⑴ SdOa#U)
//ps.addBatch();⑵ E[:eMJR
} zTgY=fuz
//int [] counts = ps.executeBatch();⑶ j20/Q)=h
conn.commit(); Lro[ |A
}catch(Exception e){ +-DF3(
e.printStackTrace(); OcA_m.
} finally{ |WiE`&?xP
try{ hA6
if(ps!=null) { iKJ-$x_5
ps.clearParameters(); kLsp0%2
ps.close(); WH>= *\
ps=null; )\S3Q
} o!]muO*Rm
}catch(SQLException e){} Jy#c 6
DBUtils.closeConnection(conn); dRdI('
} bW]7$?acv
} ?QDHEC62
public long getLast(){ y*F !k{P
return lastExecuteTime; wbIgZ]o!/;
} N('=qp9
public void run(){ /|<Pn!}J
long now = System.currentTimeMillis(); ,Wv@D"4?
if ((now - lastExecuteTime) > executeSep) { |/qwR~
//System.out.print("lastExecuteTime:"+lastExecuteTime); 'YKzs ;y$
//System.out.print(" now:"+now+"\n"); / [s TN.MG
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); YFJw<5&
lastExecuteTime=now; ~.Wlv;
executeUpdate(); jmp0 %:+L
} j*.K|77WHj
else{ O'm5k l
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &z;bX-"E
} TANv)&,|9
} i;flK*HOZ9
} -w dbH`2Z"
//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 e^LjB/<Th
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类写好了,下面是在JSP中如下调用。 XIGz_g;#'w
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<% B\73Vf
CountBean cb=new CountBean(); kB)u@`</mV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); i/C`]1R/
CountCache.add(cb); }508wwv
out.print(CountCache.list.size()+"<br>"); \aN*x
CountControl c=new CountControl();
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c.run(); t3qPocYQ
out.print(CountCache.list.size()+"<br>"); Silh[8
%>