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: C#h76fpH
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CountBean.java !-ZP*V3}h
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/* sS|<&3
* CountData.java Rf?%Tv0\
* O{nC^`X
* Created on 2007年1月1日, 下午4:44 g}YToOs
* B*2{M
* To change this template, choose Tools | Options and locate the template under zsQF,7/}B
* the Source Creation and Management node. Right-click the template and choose qh H+m
* Open. You can then make changes to the template in the Source Editor. c&b/Joi7@
*/ :l;,m}#@
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package com.tot.count; 8yvJ`eL-
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/** i(P>Y2s
* M/l95fp
* @author *#6|!%?g
*/ 2^J/6R$
public class CountBean { 7N6zqjIB
private String countType; hR0]8l|
int countId; r.?+gW!C
/** Creates a new instance of CountData */ A]#_"fayo
public CountBean() {} W#VfX!~
public void setCountType(String countTypes){ [NjajA~z>F
this.countType=countTypes; 8;0^'Qr8
} ~T7\8K+ $
public void setCountId(int countIds){ 7BS/T
this.countId=countIds; <\p&jk?
} Z@u ;Z[@
public String getCountType(){ %xHu,*
return countType; &*jixqzvn
} %uW<
public int getCountId(){ R@&?i=gk
return countId; }-dF+m:
} v|>BDN@,6
} tpE3|5dZF
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CountCache.java TtZrttCE6
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/* ^>eFm8`N
* CountCache.java Nl=+.d6Qo
* +yvBSpY
* Created on 2007年1月1日, 下午5:01 0$!.c~
* sv@}x[L
* To change this template, choose Tools | Options and locate the template under [|jIC
* the Source Creation and Management node. Right-click the template and choose .N&QW
`
* Open. You can then make changes to the template in the Source Editor. /%;/pi
*/ $sM]BE:
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package com.tot.count; 4">84,-N
import java.util.*; N*?
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/** CO7CNN
* )|Jr|8
* @author ,I=O"z>9
*/ 6B
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public class CountCache { Z"+(LO!
public static LinkedList list=new LinkedList(); RBPYGu'6B
/** Creates a new instance of CountCache */ c'SM>7L
public CountCache() {} \/pVcR
public static void add(CountBean cb){ N0=b[%g;n
if(cb!=null){ ?fm2qrV@fp
list.add(cb); \#HL`R"
} N#mK7|\c?:
} dfnX!C~6 \
} eUYG96Jw
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CountControl.java dnk1Mu<
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/* 3$;J0{&[i
* CountThread.java N
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* Ogn,1nm%
* Created on 2007年1月1日, 下午4:57 oK%K+h
* #xDDh`
* To change this template, choose Tools | Options and locate the template under +38Lojb}
* the Source Creation and Management node. Right-click the template and choose e$gaE</
* Open. You can then make changes to the template in the Source Editor. x[zKtX
*/ Tm0?[[3hC
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package com.tot.count; <ihhV e
import tot.db.DBUtils; Gt?!E6^!
import java.sql.*; f45x%tha %
/** tPQ2kEW
* }6F_2S3c
* @author NWaI[P
*/ }kpfJLjY
public class CountControl{ }x>}:"P;W
private static long lastExecuteTime=0;//上次更新时间 bwv/{3G,Ys
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 vr5<LNCLQ
/** Creates a new instance of CountThread */ (8+.#1!*
public CountControl() {} hrUm}@d
public synchronized void executeUpdate(){ )WzGy~p8K
Connection conn=null; 3XM Bu*
PreparedStatement ps=null; \;4L~_2$q
try{ -<u-
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conn = DBUtils.getConnection(); yN%3w0v
conn.setAutoCommit(false); Q3'(f9
x
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ] `b<"
for(int i=0;i<CountCache.list.size();i++){ [J(@$Qix
CountBean cb=(CountBean)CountCache.list.getFirst(); EY=\C$3J:
CountCache.list.removeFirst(); bL6L-S
ps.setInt(1, cb.getCountId()); ufHuI*
ps.executeUpdate();⑴ 6yV5Yjs
//ps.addBatch();⑵ PTfN+
} ";%e~
=
//int [] counts = ps.executeBatch();⑶ ?Yynd
conn.commit(); /r #b
}catch(Exception e){ 7R%
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e.printStackTrace(); $sB48LJuU'
} finally{ My`josJ`Pb
try{ $fq-wl-=
if(ps!=null) { n3-GnVC][
ps.clearParameters(); 4+Li)A:4.
ps.close(); p7?CeyZ-V
ps=null; k:&?$
} h+ `J=a|\
}catch(SQLException e){} 5x93+DkO\
DBUtils.closeConnection(conn); eP-R""uPw
} r? 6Z1
} 8+@1wks
public long getLast(){ R]V~IDs
return lastExecuteTime; f=-!2#%
} zM3H@;}m
public void run(){ nA{ncTg1\
long now = System.currentTimeMillis(); 98"z0nI%
if ((now - lastExecuteTime) > executeSep) { sYW1T @
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3"2<T^H]
//System.out.print(" now:"+now+"\n"); n]kQtjJ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); fS8XuT
lastExecuteTime=now; _ d(Ks9
executeUpdate(); v ](G?L9b
} |TNiKy
else{ &Nj:XX;X
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Gx~"iM
} Cv?<}q
} +qu@dU0\`|
} x _YV{
//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 9/8@
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类写好了,下面是在JSP中如下调用。 wd2P/y42;;
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<% <Bob#Tf
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CountBean cb=new CountBean(); .3g\[p
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); GSUOMy[M-
CountCache.add(cb); @ B}c4,
out.print(CountCache.list.size()+"<br>"); &j
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CountControl c=new CountControl(); .yHHogbt
c.run(); eX]9mQ]E
out.print(CountCache.list.size()+"<br>"); lL(}dbT~N
%>