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: dl+:u}9M$
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CountBean.java *yN#q>1
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/* }a!c
* CountData.java 8jz7t:0
* 2E@g#:3
* Created on 2007年1月1日, 下午4:44 ;qaNIOo9
* J['i
* To change this template, choose Tools | Options and locate the template under Xe@:Aun
* the Source Creation and Management node. Right-click the template and choose c? >;UzM
* Open. You can then make changes to the template in the Source Editor. d%#5roR4<
*/ %APeQy"6#^
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package com.tot.count; p`}G"DM
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/** !XT2'6nu
* B X Et]+Q
* @author Mi7LyIu
*/ 2]+f<Z[/
public class CountBean { !uAqY\Is
private String countType; {r_x\VC=p
int countId; :Kk+wp}f#
/** Creates a new instance of CountData */ $pj;CoPm
public CountBean() {} ~!"z`&
public void setCountType(String countTypes){ Wn5xX5H C
this.countType=countTypes; s \q
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} L^??*XEUJ
public void setCountId(int countIds){ Z!I#Z2X
this.countId=countIds; d+%Rg\v
} t ]P^6jw'
public String getCountType(){ @MfZP~T+
return countType; ML:H\
} APq Yf<W
public int getCountId(){ (gb
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return countId; W!)B%.Q
} "/{H=X3was
} =&y6mQ
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CountCache.java $q0i=l&$&
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/* b.QL\$a
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* CountCache.java K#[z5
* uw{K&Hxw
* Created on 2007年1月1日, 下午5:01 B=|m._OL]n
* U\(T<WX,
* To change this template, choose Tools | Options and locate the template under c:`CL<xzU
* the Source Creation and Management node. Right-click the template and choose .CEl{fofj
* Open. You can then make changes to the template in the Source Editor. k.W1bF9n6
*/ II{"6YI>
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package com.tot.count; HA3d9`
import java.util.*; ~jMfm~
/** E/3<8cV
* u*8x.UE8C0
* @author Imz1"+E~
*/ C ,[q#D4
public class CountCache { sdXZsQw
public static LinkedList list=new LinkedList(); FXFyF*w2
/** Creates a new instance of CountCache */ 1_5]3+r_U-
public CountCache() {} b}Wm-]|+
public static void add(CountBean cb){ aThvq%;
if(cb!=null){ H*h4D+Kxv
list.add(cb); AzFS6<_
} IAb-O
} R;H>#caJ
} . 12H/F
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CountControl.java ,`ju(ac!
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/* !]=S A &
* CountThread.java ONm-zRx|
* [*^rH:
* Created on 2007年1月1日, 下午4:57 ]3CWb>!_
* YI+o:fGC5
* To change this template, choose Tools | Options and locate the template under J6g:.jsK!
* the Source Creation and Management node. Right-click the template and choose eOs 4c`
* Open. You can then make changes to the template in the Source Editor. @T&w
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*/ y:,m(P
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package com.tot.count; `W'S'?$
import tot.db.DBUtils; m4RiF
import java.sql.*; :zsMkdU
/** `f\+aD'u
* HKG8X="
* @author ant#bDb/
*/ .[S\&uRv
public class CountControl{ -E-e!
private static long lastExecuteTime=0;//上次更新时间 _E4_k%8y
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;6{{hc4
/** Creates a new instance of CountThread */ s1
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public CountControl() {} jF|LPWl
public synchronized void executeUpdate(){ $im6v
Connection conn=null; cD]#6PFA
PreparedStatement ps=null; Z2&7HTz
try{ +"JQ5~7
conn = DBUtils.getConnection(); 8W}rSv+
conn.setAutoCommit(false); Hzojv<c
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); l` ?4O
for(int i=0;i<CountCache.list.size();i++){ A\QrawBp0l
CountBean cb=(CountBean)CountCache.list.getFirst(); =$WDB=i
CountCache.list.removeFirst(); ?xb2jZ/0X
ps.setInt(1, cb.getCountId()); tW"s^r=95
ps.executeUpdate();⑴ lfyij[6q+
//ps.addBatch();⑵ x(y=.4Yf+
} xH{V.n&v
//int [] counts = ps.executeBatch();⑶
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conn.commit(); u^+
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}catch(Exception e){ ]RTK:%
e.printStackTrace(); T,5(JP(h3
} finally{ NU.YL1
try{ /|,:'W%U
if(ps!=null) { Y!3i3D
ps.clearParameters(); `{'h+v`
ps.close(); *2r(!fJP=^
ps=null; 06>+loBG
} aIklAj)=
}catch(SQLException e){} XseP[
DBUtils.closeConnection(conn); [A#>G4a<
} 7WEoyd
} GW!%DT
public long getLast(){ &ej|DM6
return lastExecuteTime; 884 -\M"h
} ms/Q-
public void run(){ ~uh,R-Q$
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { #An_RU6h
//System.out.print("lastExecuteTime:"+lastExecuteTime); wo_iCjmK
//System.out.print(" now:"+now+"\n"); 0t.v
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); p@%H.
5&&
lastExecuteTime=now; Y$nI9
executeUpdate(); <M M(Z
} fx= %e
else{ `;z;=A*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); V; 1i/{
} `lN
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} MTeCmFe0;
} N A9ss
//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 jQY^[A
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类写好了,下面是在JSP中如下调用。 vff`Xh>k(
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<% W Z^u%Z
CountBean cb=new CountBean(); Pc=:j(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ]hlYmT
CountCache.add(cb); +V/m V7FK
out.print(CountCache.list.size()+"<br>"); }BLT2]y0
CountControl c=new CountControl(); 'kk
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c.run(); jjJ l\Vn
out.print(CountCache.list.size()+"<br>"); SAGECK[Ix
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