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: x , Vh
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CountBean.java 0^}'+t,lc
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/* z/0yO@_D/q
* CountData.java }WO9!E(
* EARfbb"SG7
* Created on 2007年1月1日, 下午4:44 JC&6q>$
* )y`TymM[F
* To change this template, choose Tools | Options and locate the template under oB0 8
* the Source Creation and Management node. Right-click the template and choose ] `B,L*m6
* Open. You can then make changes to the template in the Source Editor. N$%61GiulT
*/ >{ECyh;
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package com.tot.count; r2SJp@f
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/** o9i#N
* Qb?y@>-[
* @author AGEZ8(h
*/ ByhOK}u;P4
public class CountBean { 3|~(?4aE
private String countType; V9zywM
int countId; ?..i 4
/** Creates a new instance of CountData */ WbQhlsc:
public CountBean() {} mX@j
public void setCountType(String countTypes){ mNx,L+3
this.countType=countTypes; *9dV/TT~f[
} gp$EXJ=
public void setCountId(int countIds){ W1?!iE~tO
this.countId=countIds; 2{mY:\
} z [qdmx^
public String getCountType(){ ?-8y4
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return countType; "J P{Q
} >HcYVp~G
public int getCountId(){ TwM1M["3
return countId; m|[\F#+C
} nY{i>Y
} NokXE
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CountCache.java gb=80s0
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/* ~>#LOT `
* CountCache.java Ql~#((K
* _\,rX\
* Created on 2007年1月1日, 下午5:01 ^91sl5c8yD
* 5ys#L&q'Z
* To change this template, choose Tools | Options and locate the template under wTTTrk
* the Source Creation and Management node. Right-click the template and choose iN<(O7B;
* Open. You can then make changes to the template in the Source Editor. X2\E9hJg
*/ X)Dqeb6
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package com.tot.count; "JzfL(yt
import java.util.*; S9G8aea/
/** rDIhpT)a
* MV0<^/p|
* @author 4ef*9|^x#
*/ a9#W9eP
public class CountCache { w::r?.9
public static LinkedList list=new LinkedList(); ^273l(CZ1
/** Creates a new instance of CountCache */ <Gr9^C
public CountCache() {} n 5~=qQK2
public static void add(CountBean cb){ CgVh\4,a
if(cb!=null){ A$7Eo`Of
list.add(cb); 7<EJo$-j
} fd?bU|I_2
} h'B9|Cm
} kF+ZW%6N
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CountControl.java Az
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/* 968Ac}OA
* CountThread.java 4)c+t"h
* IIq"e~"Vs
* Created on 2007年1月1日, 下午4:57 T@(6hEmP,
* LKqRvPnh
* To change this template, choose Tools | Options and locate the template under R'G'&H{N
* the Source Creation and Management node. Right-click the template and choose xik`W!1S
* Open. You can then make changes to the template in the Source Editor. <9@&oN+T
*/ "0|BoG
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package com.tot.count; 5Xwk*@t2a
import tot.db.DBUtils; 3%XG@OgP
import java.sql.*; o*%3[HmV
/** *Jb_=j*)
* |.j^G2x
* @author w`M]0'zls
*/ OYBotk]{1
public class CountControl{ M'^(3#ZU
private static long lastExecuteTime=0;//上次更新时间 C0zrXhY_v
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @(i*-u3Tq
/** Creates a new instance of CountThread */ -"F0eV+y
public CountControl() {} 8dc538:q}
public synchronized void executeUpdate(){ _kh>Z
Connection conn=null; %v]7BV^%6
PreparedStatement ps=null; ER{yuw
try{ ha_@Yqgh
conn = DBUtils.getConnection(); IK8%Q(.c
conn.setAutoCommit(false); L<0=giE
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); xC)7eQn/R
for(int i=0;i<CountCache.list.size();i++){ w'd.;
CountBean cb=(CountBean)CountCache.list.getFirst(); GSQfg
CountCache.list.removeFirst(); a|UqeNI{
ps.setInt(1, cb.getCountId()); r k@UsHy
ps.executeUpdate();⑴ - dl}_
//ps.addBatch();⑵ gk"mr_03
} D2Y&[zgv
//int [] counts = ps.executeBatch();⑶ 0HjJaML
conn.commit(); ab{;Z5O
}catch(Exception e){ !{IC[g n
e.printStackTrace(); h>dxBN
} finally{ ]yo_wGiwY
try{ F\JLbY{x]
if(ps!=null) { aJI>FTdK
ps.clearParameters(); l x7Kw%
ps.close(); fzl=d_
ps=null; 3KtAK9PT
} pNuqT*
}catch(SQLException e){} b<\$d4Qy
DBUtils.closeConnection(conn); {&uT3*V1
} 9 >%+bA(
} o1U}/y+R\
public long getLast(){ w.tW=z5
return lastExecuteTime; >
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} BjYOfu'~z
public void run(){ H;qJH1EdD
long now = System.currentTimeMillis(); )+?HI^-[S
if ((now - lastExecuteTime) > executeSep) { 0"TgLd
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y7-*2"!
//System.out.print(" now:"+now+"\n"); 4*iHw+%mq
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9-b 8`|s
lastExecuteTime=now; 02,W~+d1
executeUpdate(); &uPDZ#C-
} dnix:'D1
else{ t{~@I
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Hv3W{|
} (e(Rr4
} gNTh% e
} 1f<RyAE?5
//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 cu<y8
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类写好了,下面是在JSP中如下调用。 ikr7DBLt
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<% Uh*@BmDA
CountBean cb=new CountBean(); {f-XyF1`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )PwQ^||{
CountCache.add(cb); +uELTHH=
out.print(CountCache.list.size()+"<br>"); w3d34*0$
CountControl c=new CountControl(); ^eobp.U
c.run(); |Hfl&3
out.print(CountCache.list.size()+"<br>"); C*a,<`
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