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: ] 6Y6q])Z
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CountBean.java s2=`haYu
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/* wXR7Ifrv
* CountData.java f]sc[_n]
* \wR;N/tg
* Created on 2007年1月1日, 下午4:44 '@6O3z_{
* S =5br
* To change this template, choose Tools | Options and locate the template under "!S7D>2y#
* the Source Creation and Management node. Right-click the template and choose %+pF4f8]
* Open. You can then make changes to the template in the Source Editor. _-=yD@;[D
*/ _^ZBSx09)
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package com.tot.count; !kW~s_gUb*
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/** Ll$,"}0T
* Vq&}i~
* @author
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*/ zp'Vn7
public class CountBean { qV{iUtYt
private String countType; g:oB j6$
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int countId; j{$2.W$
/** Creates a new instance of CountData */ @|2sF
public CountBean() {} '"m-kor
public void setCountType(String countTypes){ fK/|0@B8
this.countType=countTypes; >,6%Y3
} :pJKZ2B,
public void setCountId(int countIds){ T)#e=WcP]
this.countId=countIds; b3 NEYn
} >PS`;S!(
public String getCountType(){ vu@@!cT6e
return countType; 1xTNrLW
} Um~DA
public int getCountId(){ BMdcW
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return countId; pqF!1
} P=<>H9p:o
} c BcZ@e;
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CountCache.java 'O^<i`8U]
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/* ?Gnx!3Q
* CountCache.java Ud:;kI%Vj
* ThiM6Hb
* Created on 2007年1月1日, 下午5:01 U[O7}Nsb"
* 'T+v&M
* To change this template, choose Tools | Options and locate the template under f0@4>\g
* the Source Creation and Management node. Right-click the template and choose {i"th(J$
* Open. You can then make changes to the template in the Source Editor. Oil~QAd,
*/ oiRrpS\T.
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package com.tot.count; $!goM~pZ
import java.util.*; ,a34=,
/** "1wjh=@z
* .b|!FWHNS
* @author q[TGEgG
*/ D KRF#*[=d
public class CountCache { (zml704dI)
public static LinkedList list=new LinkedList(); yPoa04!{=
/** Creates a new instance of CountCache */ e_+SBN1`P&
public CountCache() {} ' OXL'_Xl
public static void add(CountBean cb){ Dqg01_O9O
if(cb!=null){ VQ7A"&hh
list.add(cb); rI#,FZ
} cU_:l.b
} duV\Kt/g^
} /0YO`])"
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CountControl.java Gp0yRT.
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/*
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* CountThread.java 7-Mm+4O9
* }B`T%(11=
* Created on 2007年1月1日, 下午4:57 !B/5@P
* MLvd6tIv,
* To change this template, choose Tools | Options and locate the template under kYZj^tR
* the Source Creation and Management node. Right-click the template and choose HhB&vi
* Open. You can then make changes to the template in the Source Editor. "IJ 9vXI
*/ tjJi|
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package com.tot.count; |t6 :4']
import tot.db.DBUtils; z7!@^!r
import java.sql.*; UM}MK
/** 2O(= 2X
* p5Wz.n.<'
* @author b *Ca*!
*/ |xFSGrC
public class CountControl{ }qg.Go
private static long lastExecuteTime=0;//上次更新时间 m](q,65 2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 bScW<DZJ-
/** Creates a new instance of CountThread */ /s
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public CountControl() {} Zvkb=
public synchronized void executeUpdate(){ \:jJ{bl^A
Connection conn=null; `zOn(6B;U
PreparedStatement ps=null; -Mzm~@_s]
try{ ,In}be$:
conn = DBUtils.getConnection(); <O3,b:vw
conn.setAutoCommit(false); WesEZ\V
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); AGV+Y6
for(int i=0;i<CountCache.list.size();i++){ TG6E^3a P
CountBean cb=(CountBean)CountCache.list.getFirst(); Qe;R3D=T;
CountCache.list.removeFirst(); .R_-$/ZP
ps.setInt(1, cb.getCountId()); ,.i)(Or
ps.executeUpdate();⑴ #{g6'9PMz
//ps.addBatch();⑵ YhO-ecN
} 8Z>=sUMQ
//int [] counts = ps.executeBatch();⑶ MI,kKi
conn.commit(); (/jZ&4T
}catch(Exception e){ @DuSii#.S
e.printStackTrace(); %I#[k4,N
} finally{ rnP *}
try{ Gj&`+!\
if(ps!=null) { S\0?~l"}
ps.clearParameters(); 'wjL7PI
ps.close(); r:5u(2
ps=null; q|QkJr<
} J3y4D}
}catch(SQLException e){} <_#a%+5d
DBUtils.closeConnection(conn); ]SL0Mn g8
} ys9'1+9
} n{=N f|=
public long getLast(){ >{eGSSG0
return lastExecuteTime; /-Y.A<ieN8
} )#v0.pE
public void run(){ AEo
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { b G/[mZpRT
//System.out.print("lastExecuteTime:"+lastExecuteTime); j7qGZ"8ak
//System.out.print(" now:"+now+"\n"); N*'d]P2P`J
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Eb89B%L62G
lastExecuteTime=now; HME`7 dw?
executeUpdate(); )KKmV6>b
} B`?5G\7L
else{ v4VP7h6uD)
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); z K6'wL!!I
} }TG=ZVi
} =j~Xrytn
} &6^QFqqW`-
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 /^':5"=o
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类写好了,下面是在JSP中如下调用。 _$m1?DZ
=-;J2Qlg6
<% L+Q.y~
CountBean cb=new CountBean(); c4iGtW
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); c52S2f7
CountCache.add(cb); :tT6V(-W
out.print(CountCache.list.size()+"<br>"); 3>%:%bP
CountControl c=new CountControl(); mH9_HK.C
c.run(); A;7At!kK
out.print(CountCache.list.size()+"<br>"); tjbI*Pw7(
%>