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: cNN_KA
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CountBean.java ;c~DBJg'|
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/* ]*S_fme
* CountData.java A&'HlI%J
* F0NNS!WP7^
* Created on 2007年1月1日, 下午4:44 DA4!-\bt@
* `~t$k7wm=
* To change this template, choose Tools | Options and locate the template under Pb D|7IM
* the Source Creation and Management node. Right-click the template and choose qj|B #dU
* Open. You can then make changes to the template in the Source Editor. E{9{%J
*/ YpZ9h@,
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package com.tot.count; 6ud<B
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/** `V ++})5v
* q14A'XW
* @author UE\@7
*/ ]*;+ U6/?
public class CountBean { "=!QSb
private String countType; w1A&p
int countId; ]O&A:Us
/** Creates a new instance of CountData */ Ip0@Q}^
public CountBean() {} 'E8dkVlI
public void setCountType(String countTypes){ s?K4::@Fv
this.countType=countTypes; .Lu=16
} 5p{tt;9[
public void setCountId(int countIds){ s: q15"
this.countId=countIds; m9>nvrQ
} *t |j+*c}
public String getCountType(){ .'AHIR&>
return countType; u&I~%s
} ~(0Y`+gC
public int getCountId(){ j'0*|f ^z
return countId; /0YNB)
} vDOeBw=
} IO_H%/v"jC
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CountCache.java <ct {D|mm
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/* Z*e7W O.
* CountCache.java t@19a6:Co
* nt[0krG
* Created on 2007年1月1日, 下午5:01 " Gn; Q-@
* U ._1'pW
* To change this template, choose Tools | Options and locate the template under =yNHJHRA#
* the Source Creation and Management node. Right-click the template and choose #XY]@V\
* Open. You can then make changes to the template in the Source Editor. cwC,VYVl
*/ J2[QHr&tn
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package com.tot.count; \M532_w
import java.util.*; }w]xC
/** >qUO_>
* 8"*$e
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* @author b~1p.J4
*/ !<6wrOMa O
public class CountCache { `oz7Q(`
public static LinkedList list=new LinkedList(); ".i{WyTt
/** Creates a new instance of CountCache */ $xZk{ rK
public CountCache() {} o5$K^2^g
public static void add(CountBean cb){ t@ JPnA7~
if(cb!=null){ a&ByV!%%+_
list.add(cb); ft6^s(t
} A0X0t
} O.}gG6u5
} tB3CX\e
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CountControl.java V=*J9~K
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/* <d5vVn
* CountThread.java I!<v$
* 8k`zMT
* Created on 2007年1月1日, 下午4:57 d,+n,;6Cf
* jb![ Lp
* To change this template, choose Tools | Options and locate the template under i
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* the Source Creation and Management node. Right-click the template and choose t5Mo'*j
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* Open. You can then make changes to the template in the Source Editor. d$,i?d,
*/ -pGt;
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package com.tot.count; *_wef/==
import tot.db.DBUtils; Q%xY/xH]
import java.sql.*; ?(<AT]h V:
/** pOYtN1uN|
* YPy))>Q>cK
* @author G([vy#p
*/
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public class CountControl{ {G0)mp,
private static long lastExecuteTime=0;//上次更新时间 bg*{1^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 (}}8DB
/** Creates a new instance of CountThread */ RZtL<2.@
public CountControl() {} uY~A0I5Z
public synchronized void executeUpdate(){ Bw=[g&+o1@
Connection conn=null; g&vEc1LNo
PreparedStatement ps=null; bX(*f>G'
try{ wqOhJYc
conn = DBUtils.getConnection(); ,;-*q}U
conn.setAutoCommit(false); L K~,
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?mAw"Rb!
for(int i=0;i<CountCache.list.size();i++){ LG|,g3&
CountBean cb=(CountBean)CountCache.list.getFirst(); c6m,oS^
CountCache.list.removeFirst(); w;$+7
ps.setInt(1, cb.getCountId()); qU
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ps.executeUpdate();⑴ ui{_w @o
//ps.addBatch();⑵ {LD8ie|x1`
} y4L9Cxvs
//int [] counts = ps.executeBatch();⑶ NFc8"7Mz}
conn.commit(); a!K;8#xc
}catch(Exception e){ \-0` %k"&
e.printStackTrace(); rw2|1_AF
} finally{ DS2$ w9!
try{ L>b,}w
if(ps!=null) { "y0A<-~
ps.clearParameters(); 9.=#4OH/
ps.close(); 8W>l(w9M
ps=null; 6<Wr
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} j[`?`RyU
}catch(SQLException e){} m6cW
DBUtils.closeConnection(conn); [AzN&yACE
} fNJ;{
} %4Zy1{yKs_
public long getLast(){ jf/9]`Hf
return lastExecuteTime; 6I#DlAU@v
} $IT9@}*{
public void run(){ wcf_5T
long now = System.currentTimeMillis(); ACYn87tq
if ((now - lastExecuteTime) > executeSep) { ;alFK*K6
//System.out.print("lastExecuteTime:"+lastExecuteTime); bVHi3=0{
//System.out.print(" now:"+now+"\n"); |pR$' HO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [;AcV73
lastExecuteTime=now; }AqD0Qd2Hj
executeUpdate(); Y7)@(7G)\
} 2oG|l!C
else{ " G6jUTt
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8w[EyVHA
} 9Ol_z\5
} CM1a<bV<
} `=DCX%Vw
//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 8|NJ(D-$
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类写好了,下面是在JSP中如下调用。 r_E)HL/A
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<% ji
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CountBean cb=new CountBean(); ~{G:,|`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); c.Z4f7
CountCache.add(cb); S\;.nAR
out.print(CountCache.list.size()+"<br>"); \=_q{
CountControl c=new CountControl(); ^(*O$N*#
c.run(); )6
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out.print(CountCache.list.size()+"<br>"); !cwVJe
%>