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: 1d/NZJ9
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CountBean.java +.S#=
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/*
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* CountData.java y>>vGU;
* UaH26fWs
* Created on 2007年1月1日, 下午4:44 lTxY6vi
* @c6"RHG9
* To change this template, choose Tools | Options and locate the template under \s.1R/TyD
* the Source Creation and Management node. Right-click the template and choose P#w}3^
* Open. You can then make changes to the template in the Source Editor. r hiS
*/ m$7x#8gF
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package com.tot.count; m5X3{[a:
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/** wy,Jw3
* wCV>F-
* @author 5dg-d\6S
*/ UN-T^
public class CountBean { \R6;Fef
private String countType; =Dh$yC-Zr
int countId; oP+kAV#]
/** Creates a new instance of CountData */ 44'=;/
public CountBean() {} n33JTqX
public void setCountType(String countTypes){ 1y},9ym
this.countType=countTypes; [B}1z
} 7k'=F m6za
public void setCountId(int countIds){ [SCw<<l<
this.countId=countIds; hO^&0?
} hZp=BM"bJ
public String getCountType(){ 8]sTX9
return countType; 'q{PtYr
} >(IITt
public int getCountId(){ }%-UL{3%
return countId; 6.7`0v?,n
} vh<]aiY
} //#xK D
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CountCache.java I(z>)S'7r
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/* A Oby*c
* CountCache.java (iHf9*i CV
* B@ZqJw9J[
* Created on 2007年1月1日, 下午5:01 @o}1n?w
* `V]egdO
* To change this template, choose Tools | Options and locate the template under u&1j>`~qJ
* the Source Creation and Management node. Right-click the template and choose =nJOaXR0
* Open. You can then make changes to the template in the Source Editor. g2+l@$W
*/ o,*folL
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package com.tot.count; &eThH,w$2
import java.util.*; w^ixMn~nLF
/** *Te4U5F
* E9yFREvQc
* @author "2)+)Db
*/ * \=2KIF'
public class CountCache { mtSNl|O&{
public static LinkedList list=new LinkedList(); =?meO0]y
/** Creates a new instance of CountCache */ r!{w93rPX
public CountCache() {} y+K7WUwhq
public static void add(CountBean cb){ )z]q"s5 Y
if(cb!=null){ anHBySI3
list.add(cb); PY^^^01P
} 8C*6Fjb#
} J>HLQP
} Ck ~V5
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CountControl.java PphR4 sIM
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/* >u BV
* CountThread.java
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* ~[d=s
* Created on 2007年1月1日, 下午4:57 Nb^zkg
* /3)YWFZZc
* To change this template, choose Tools | Options and locate the template under u~/M
* the Source Creation and Management node. Right-click the template and choose !A'`uf4u
* Open. You can then make changes to the template in the Source Editor.
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*/ GNhtnB
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package com.tot.count; OYqYI!N/
import tot.db.DBUtils; "C$!mdr7
import java.sql.*; )
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/** Bq$e|t)'
* -4*'WzWr
* @author s=^r/Sz902
*/ u^#4G7<
public class CountControl{ l}2%?d
private static long lastExecuteTime=0;//上次更新时间 %\(y8QV
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {Y3_I\H8{
/** Creates a new instance of CountThread */ `nd#< w>
public CountControl() {} p|bc=`TD
public synchronized void executeUpdate(){ ,<uiitOo
Connection conn=null; Pe+ 8~0o=R
PreparedStatement ps=null; U /1[~429
try{ mV:RmA
conn = DBUtils.getConnection(); (ybtXoQs
conn.setAutoCommit(false); br34Eh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); O?C-nw6kP
for(int i=0;i<CountCache.list.size();i++){ Sy+]SeF&
CountBean cb=(CountBean)CountCache.list.getFirst(); Uy$U8b-ov
CountCache.list.removeFirst(); Y{Y;EY4
ps.setInt(1, cb.getCountId()); }5o~R~H
ps.executeUpdate();⑴ U:mq7Rd8
//ps.addBatch();⑵ PBxK>a
} v @$evmA
//int [] counts = ps.executeBatch();⑶ 'f=) pc#&g
conn.commit(); Ckl7rpY+
}catch(Exception e){ jm#d7@~4
e.printStackTrace(); _SBp66
r
} finally{ H0D>A<Ue
try{ SQ~N X)
if(ps!=null) { a`EGx{q(
ps.clearParameters(); :|n>H+Y
ps.close(); g:.,}L
ps=null; *O(/UVuD\
} o@<6TlZM
}catch(SQLException e){} ecY ^C3+S
DBUtils.closeConnection(conn); @n~>j&Kp
} 4i[v
ew
} 5oT2)yz
public long getLast(){ m'Ek p
return lastExecuteTime; L#7)X5a__
} [x$eF~Kp
public void run(){ -CU7u=*b
long now = System.currentTimeMillis(); A]tf>H#1
if ((now - lastExecuteTime) > executeSep) { Kh:#S|
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;G%wc!
//System.out.print(" now:"+now+"\n"); j$|Yd=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); G)tq/`zNw
lastExecuteTime=now; )F%wwc^r
executeUpdate(); rx}ujjx
} e~t}z_>F
else{ \4\\575zp'
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); c5B_WqjJ
} gq/ePSa
} qSpa4W[
} +c]N]?k&
//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?g]qy,1)
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类写好了,下面是在JSP中如下调用。 zCGmn& *M
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<% 7?Qt2tr
CountBean cb=new CountBean(); D)O6|DiO
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0'V-
CountCache.add(cb); skR,M=F~
out.print(CountCache.list.size()+"<br>"); ld!6|~0U
CountControl c=new CountControl(); +QXYU8bYZ
c.run(); uwH)/BW)[
out.print(CountCache.list.size()+"<br>"); EMW4<