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: #mioT",bm=
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CountBean.java L#D)[v"
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/* i+Ne.h
* CountData.java 1mh7fZgn
* \Rt>U|%
* Created on 2007年1月1日, 下午4:44 U1yspHiZ
* 8%; .H-
* To change this template, choose Tools | Options and locate the template under W }Ll)7(|T
* the Source Creation and Management node. Right-click the template and choose -'oxenu
* Open. You can then make changes to the template in the Source Editor. ]We0 RD"+
*/ Vl(id_~ _
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package com.tot.count; N>s3tGh
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/** A[Ce3m
* ,o
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* @author $Zi{1w
*/ SoCN.J30
public class CountBean { I_Gm2Dd
private String countType; Z0~,cO8~
int countId; RXWdqaENx
/** Creates a new instance of CountData */ RY,L'GtO
public CountBean() {} |e+r~).4B
public void setCountType(String countTypes){ pP\^bjI
this.countType=countTypes; sBxCi~
} o9{1_7K
public void setCountId(int countIds){ ]G!
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this.countId=countIds; "|WKK}
} A6;[r #C
public String getCountType(){ &`"uKO]
return countType; ye
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} dDYor-g>
public int getCountId(){ #LYx;[D6
return countId; >^f]Lgp
} nwDW<J{f|U
} {!4ZRNy(k
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CountCache.java 5tVg++I
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/* Yk7^?W
* CountCache.java =lh&oPc1
* 5B{Eg?
* Created on 2007年1月1日, 下午5:01 ,+5!1>\
* (elkk#
* To change this template, choose Tools | Options and locate the template under @<S'f<>g
* the Source Creation and Management node. Right-click the template and choose %CrpUx
* Open. You can then make changes to the template in the Source Editor. 61b<6r0o
*/ 'Te'wh=Y
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package com.tot.count; kgX"I ?>d
import java.util.*; 0M}Ql5+h,
/** i8/"|+Z
* x}7Xd P.2$
* @author 0w$1Yx~C
*/ ',Oc+jLR
public class CountCache { pAtxEaXh
public static LinkedList list=new LinkedList(); FxX nX
/** Creates a new instance of CountCache */ ]`@<I'?,X
public CountCache() {} ehX4[j6
public static void add(CountBean cb){ KXo[;Db)k
if(cb!=null){ 4d-"kx3X
list.add(cb); 6A} 45
} y|#Fu
} \FIOFbwe
} z)FGbX
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CountControl.java rIj B{X{Z
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/* )]JQlm:H
* CountThread.java 04E#d.o'
* 0^MRPE|f5
* Created on 2007年1月1日, 下午4:57 M`G#cEc
* 74~%4
* To change this template, choose Tools | Options and locate the template under p:4oA<V
* the Source Creation and Management node. Right-click the template and choose \//{\d
* Open. You can then make changes to the template in the Source Editor. Znh<r[p<
*/ #|} EPD9$
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package com.tot.count; Kx,<-]4
import tot.db.DBUtils; RM`iOV,Y
import java.sql.*; bO gVCg
/** K&iU+
* R?kyJ4S
* @author Qb1hk*$=
*/ #$-`+P
public class CountControl{ H[iR8<rhQ
private static long lastExecuteTime=0;//上次更新时间 KQrG|<J
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !*-|s}e
/** Creates a new instance of CountThread */ Jpo(O>\P
public CountControl() {} NFb<fD[C
public synchronized void executeUpdate(){ %t,Fxj4F
Connection conn=null; AhSN'gWpbF
PreparedStatement ps=null; Dn.%+im-u
try{ Y X{F$BM
conn = DBUtils.getConnection(); =&?BPhJE
conn.setAutoCommit(false); zO)3MC7l*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )L7h:%h#
for(int i=0;i<CountCache.list.size();i++){ h!]=)7x;
CountBean cb=(CountBean)CountCache.list.getFirst(); i}LVBx"K(
CountCache.list.removeFirst(); $%3%&+z$I
ps.setInt(1, cb.getCountId()); ,y*|f0&"~
ps.executeUpdate();⑴ $[*<e~?
//ps.addBatch();⑵ DqBiBH[%h
} mp>Ne6\Tu
//int [] counts = ps.executeBatch();⑶ ,A!0:+
conn.commit(); p+1kU1F0
}catch(Exception e){ Sa$-Yf
e.printStackTrace(); Eg#WR&Uq"
} finally{ ksli-Px
try{ ^/$bd4,z
if(ps!=null) { kt hy9<!$
ps.clearParameters(); `9p;LZC1 K
ps.close(); S8)6@ECC
ps=null; |Skhx9};
} kG3m1: :
}catch(SQLException e){} Zm/I &
DBUtils.closeConnection(conn); Gmh6|Dsg
} 2lRE+_qz
} 7,Q>>%/0P
public long getLast(){ :^992]EBEj
return lastExecuteTime;
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} p6W|4_a?
public void run(){ lH1gWe
long now = System.currentTimeMillis(); _air'XQ&!
if ((now - lastExecuteTime) > executeSep) { 7,EdJ[CR$
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ya-kMUW
//System.out.print(" now:"+now+"\n"); I=9sTR)
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9g`o+U{
lastExecuteTime=now; [I5}q&
executeUpdate(); 5Ls
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} UrEfFtH'
else{ rl](0"Y0
t
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6Y&`mgMF'
} P
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} 5Z*6,P0
} % (x9~"
//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 YS+|n%?
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类写好了,下面是在JSP中如下调用。 FWDAG$K@0
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<% 'o]8UD(
CountBean cb=new CountBean(); zP|^) h5
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Y4I;-&d's
CountCache.add(cb); pt=H?{06
out.print(CountCache.list.size()+"<br>"); ]}0QrD
CountControl c=new CountControl(); &Z6s\r%
c.run(); tkKiuh?m
out.print(CountCache.list.size()+"<br>"); xy[aZr
%>