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: 7rg[5hP T
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CountBean.java ![tI(TPq
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/* JwczE9~o
* CountData.java ?@(H.
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* DyZ90]N
* Created on 2007年1月1日, 下午4:44 %Q~Lk]B?t
* ::` wx@
* To change this template, choose Tools | Options and locate the template under ijYLf.R<
* the Source Creation and Management node. Right-click the template and choose v a;wQ~&
* Open. You can then make changes to the template in the Source Editor. qZ}XjL
*/ N|LVLsK
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package com.tot.count; ".ZiR7Z:$Y
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/** QD~`UJe>
* YPEd
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* @author c y$$}
*/ r&DK> H
public class CountBean { |i8dI )b
private String countType; \&90$>h
int countId; %"2B1^o>
/** Creates a new instance of CountData */ lhTbg M
public CountBean() {} _F EF+I
public void setCountType(String countTypes){ /B7
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this.countType=countTypes; dp+Y?ufr
} x6tY _lzJ
public void setCountId(int countIds){ !W7ekPnK
this.countId=countIds;
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} e>)5j1
public String getCountType(){ eX@q'Zi
return countType; Uo
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} 7 '/&mX>
public int getCountId(){ Hyg?as>}u
return countId; 0k 8SDRWU
} $z]l4Hj
} /K<Nlxcm
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CountCache.java 0]~n8mB>
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/* XN;eehB?aE
* CountCache.java Wg1WY}zG
* Y<XDR:]A,
* Created on 2007年1月1日, 下午5:01 |93%,
* wP9C\W;
* To change this template, choose Tools | Options and locate the template under '5--eYG
* the Source Creation and Management node. Right-click the template and choose Vp$ckr
* Open. You can then make changes to the template in the Source Editor. -(G2@NG
*/ !c7Od
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package com.tot.count; QPEv@laM
import java.util.*; BKEB,K=K@
/** =Yk$Q\c
* 0*/~9n-Vl
* @author z-j \S7F
*/ `39U I7
public class CountCache { O.dNhd$
public static LinkedList list=new LinkedList(); /'(P{O>{j
/** Creates a new instance of CountCache */ `h'^S,'*
public CountCache() {} (I5ra_FVs
public static void add(CountBean cb){ 8Bvjj|~ (@
if(cb!=null){ ngjbE+
list.add(cb); RFdN13sJv
} Q~kwUZ
} u4'Lm+&O
} .YkKIei
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CountControl.java :xV&%Qa1
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/* 4hs4W,2!
* CountThread.java SccU@3.X~
* |7-tUHMo[
* Created on 2007年1月1日, 下午4:57 HNPr|
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* ^ytd~iK8
* To change this template, choose Tools | Options and locate the template under $j/F7.S
* the Source Creation and Management node. Right-click the template and choose : Ej IV]e
* Open. You can then make changes to the template in the Source Editor. !QovpO">z
*/ )94R\f
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package com.tot.count; ln.~ >FO
import tot.db.DBUtils; Mx
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import java.sql.*; o%.cQo=v*
/** Ow
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* U#}.r<
* @author e_TM#J(3
*/ ".u?-xcbJ
public class CountControl{ 9maw+ c!~
private static long lastExecuteTime=0;//上次更新时间 gyK"#-/_d
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 f2=s{0SX0
/** Creates a new instance of CountThread */ M: 6cma5
public CountControl() {} QbWD&8T0O
public synchronized void executeUpdate(){ &,/T<V
Connection conn=null; ){}#v&
PreparedStatement ps=null; n7G$gLX
try{ a_yV*N`D
conn = DBUtils.getConnection(); i@RjG
conn.setAutoCommit(false); }bVyvH
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); SZPu"O\
for(int i=0;i<CountCache.list.size();i++){ ?r+tU
CountBean cb=(CountBean)CountCache.list.getFirst(); 9HE)!Col
CountCache.list.removeFirst(); ;P_Zen
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ ]~P?
//ps.addBatch();⑵ 9pgct6BO
} 'K1w.hC<
//int [] counts = ps.executeBatch();⑶ =aCv
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conn.commit(); aE"t['
}catch(Exception e){ Wac8x%J
e.printStackTrace(); -=RXhE_{
} finally{ rtpjx%
try{ &}FYz8w 2/
if(ps!=null) { Qi%A/~
ps.clearParameters(); z 4-wvn<*
ps.close(); %lPP1
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ps=null; DM&"oa50
} #FcYJH
}catch(SQLException e){} CeQcnJU
DBUtils.closeConnection(conn); !>tXib]:
} ,'j5tU?c
} it,%T)2H
public long getLast(){ wKYfqNCH
return lastExecuteTime; 38#(ruv
} mf3 G$=[
public void run(){ LP~$7a
long now = System.currentTimeMillis(); Dt ?Fs
if ((now - lastExecuteTime) > executeSep) { 4c% :?H@2
//System.out.print("lastExecuteTime:"+lastExecuteTime); C {))T5G
//System.out.print(" now:"+now+"\n"); =mZw71,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); DXUI/C f
lastExecuteTime=now; 0KZ 3h|4lP
executeUpdate(); 'Zzm'pC
} sxqXR6p{
else{ ,LW0{(&z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,d7@*>T&
} +a|4XyN
} 09"~<W8
} _RmrjDk
//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.q%O1
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类写好了,下面是在JSP中如下调用。 q8oEb
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<% xQ[YQ!l
CountBean cb=new CountBean(); ji2#O.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); oGM.{\i
CountCache.add(cb); #GF1MFkoS
out.print(CountCache.list.size()+"<br>"); >M!>Hl/
CountControl c=new CountControl(); W+#?3s[FV
c.run(); @MM|.#
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out.print(CountCache.list.size()+"<br>"); +]6 EkZO
%>