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: z]%c6ty
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CountBean.java ..K@'*u
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/* +v.<Fw2k#
* CountData.java h]>QGX[kC
* P2!+ZJ&
* Created on 2007年1月1日, 下午4:44 28!
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* "M!]t,?S
* To change this template, choose Tools | Options and locate the template under f'oO/0lx
* the Source Creation and Management node. Right-click the template and choose sOyL
* Open. You can then make changes to the template in the Source Editor. ^cnTZzT#Q
*/ 4F`&W*x
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package com.tot.count; WR<?_X_
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/** @"G+kLv0
* $VxKv7:
* @author nf0]<x2
*/ \V_Tc`
public class CountBean { hjgB[
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private String countType; r6QshCA"
int countId; Ht"?ajW{
/** Creates a new instance of CountData */ \:m1{+l
public CountBean() {} Bc*FH>E
public void setCountType(String countTypes){ &|K9qa~)Y
this.countType=countTypes; *yZ `aKfH
} {zTnE?(o`
public void setCountId(int countIds){ z}a9%Fb
this.countId=countIds; fjd)/Gg
} =G9I7Y@
public String getCountType(){ rk-GQ#SKU
return countType; a_3w/9L4r
} (uVL!%61k
public int getCountId(){ W8_$]}G8E
return countId; sxn{uRF
} !kS/Ei
} k.ttrKy<q/
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CountCache.java X5tx(}j
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/* KK}ox%j
* CountCache.java kK|D&Xy`
* 6dncUfB
* Created on 2007年1月1日, 下午5:01 oMNSQMlI
* T' > MXFLh
* To change this template, choose Tools | Options and locate the template under &\y`9QpVF
* the Source Creation and Management node. Right-click the template and choose %XBMi~
* Open. You can then make changes to the template in the Source Editor. Nl'@Y^8N
*/ +,1 Ea )
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package com.tot.count; >/4N :=.h
import java.util.*; 4q"4N2
/** <Ej`zGhWz
* o1?S*
* @author x']Fe7nv
*/ Gsu?m
public class CountCache { Rc vp@
public static LinkedList list=new LinkedList(); ij,Rq`}l
/** Creates a new instance of CountCache */ #,9s\T
public CountCache() {} }a%1$>sj
public static void add(CountBean cb){ GO)5R,
if(cb!=null){ a D+4uGN
list.add(cb); wJZuJ(
} q5G`q&O5
} {e5DQ 21.
} iax0V
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CountControl.java *M^<oG
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/* cLf<YF
* CountThread.java `W:z#uNG]
* bq2f?uD-}
* Created on 2007年1月1日, 下午4:57 FeZ*c~q
* Za,myuI+
* To change this template, choose Tools | Options and locate the template under 3rY\y+m
* the Source Creation and Management node. Right-click the template and choose T&4f}g/
* Open. You can then make changes to the template in the Source Editor. U=WS]
*/ x5|^p=
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package com.tot.count; "AP$)xM-:
import tot.db.DBUtils; )Dp0swJ
import java.sql.*; B@U'7`v
/** q
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* \n`/?\r.z
* @author 4T-"\tmg/
*/ B!
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public class CountControl{ +e,c'.
private static long lastExecuteTime=0;//上次更新时间 9a]{|M9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 \zcR75
/** Creates a new instance of CountThread */ $J):yhFs e
public CountControl() {} )8!*,e=4
public synchronized void executeUpdate(){ W7. +
Connection conn=null; la}cGZ; p.
PreparedStatement ps=null; f^ja2.*%?
try{ a^8PB|G
conn = DBUtils.getConnection(); ^
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conn.setAutoCommit(false); /J(vqYK"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); d_Jj&:"l
for(int i=0;i<CountCache.list.size();i++){ Z5p
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CountBean cb=(CountBean)CountCache.list.getFirst(); h*R w^5,c
CountCache.list.removeFirst(); {a__/I>)
ps.setInt(1, cb.getCountId()); S:XsO9:{
ps.executeUpdate();⑴ 7=D,D+f
//ps.addBatch();⑵ ,5x#o
} ;80^ GDk~S
//int [] counts = ps.executeBatch();⑶ !B92W
conn.commit(); OD9z7*E@
}catch(Exception e){ 16>D?;2o(
e.printStackTrace(); P2@Z7DhQ
} finally{ RRXp9{x`
try{ 51u\am'T
if(ps!=null) { L9<\vJ
ps.clearParameters(); 3vKTCHbk9
ps.close(); J?dLI_{<
ps=null; !Sw=ns7
} 4i
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}catch(SQLException e){} ~8yh,U
DBUtils.closeConnection(conn); Z+u.LXc|c
} 51`&%V{daL
} yVgC1-8i*
public long getLast(){ T9I$6HAi
return lastExecuteTime; ]B UirJ,2
} t>AOF\
public void run(){ =7JSJ98
long now = System.currentTimeMillis(); x.#E3xI
if ((now - lastExecuteTime) > executeSep) { m^0vux
//System.out.print("lastExecuteTime:"+lastExecuteTime); F(#?-MCs
//System.out.print(" now:"+now+"\n"); $btu=_|f
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); *FktI\tS
lastExecuteTime=now; EK5$z>k>m
executeUpdate(); 0>8w On
} uorX;yekC
else{ c-PZG|<C[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); TZ+ p6M8G
} araXE~Ac
} 7f}uRXBV$A
} 14"57Jt8
//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 J
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类写好了,下面是在JSP中如下调用。 w|6/ i/X
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<% vc&v+5Y
CountBean cb=new CountBean(); pY@QR?F\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); swxX3GR
CountCache.add(cb); Pmo<t6
out.print(CountCache.list.size()+"<br>"); :dh; @kp
CountControl c=new CountControl(); &92/qRh7
c.run(); tsJR:~
out.print(CountCache.list.size()+"<br>");
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