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: H9=8nLb.
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CountBean.java Mn*v&O :
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/* hC!8-uBK5<
* CountData.java m4 c2WY6k
* ad<ZdO*h
* Created on 2007年1月1日, 下午4:44 <@c9S,@t
* Jb!s#g
* To change this template, choose Tools | Options and locate the template under @i>4k
* the Source Creation and Management node. Right-click the template and choose K pKZiUQm
* Open. You can then make changes to the template in the Source Editor. KctbNMU]k
*/ _]kw |[)
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package com.tot.count; uF@DJX}>
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/** I5E4mv0<i
* 8J0#lu
* @author o|1_I?_
*/ wEix 8Ow*
public class CountBean { V4?]NFK
private String countType; ;+~Phdy
int countId; i7O8f^|
/** Creates a new instance of CountData */ nhB.>ReAi
public CountBean() {} LHusy;<E[
public void setCountType(String countTypes){ Wl{}>F`W[
this.countType=countTypes; K^[Dz\ov5
} ?,UO$#Xm
public void setCountId(int countIds){ ^4
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this.countId=countIds; T:VFyby\w
} 26-K:"
public String getCountType(){ 4^K<RSYs
return countType; gYa
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} k mX:~KMb
public int getCountId(){ ;<s0~B#9}
return countId; =R||c
} cD9axlJ
} NfXEW-
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CountCache.java ka| 8 _C^z
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/* $McbVn)~f
* CountCache.java V?-OI>
* F)uS2
* Created on 2007年1月1日, 下午5:01 ),U>AiF]
* y(=$z/
* To change this template, choose Tools | Options and locate the template under
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K)U
* the Source Creation and Management node. Right-click the template and choose Aw7_diK^
* Open. You can then make changes to the template in the Source Editor. S0p[Kt
*/ [UYE.$Y#(
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package com.tot.count; ~cW,B}
import java.util.*; nB#XQ8Nzx^
/** E9v_6d[
* F@kd[>/[
* @author VK]sK e
*/ s92SN F}g
public class CountCache { 0tp3mYd
public static LinkedList list=new LinkedList(); +jGSD@32>
/** Creates a new instance of CountCache */ ])$Rw$`w
public CountCache() {} %j2ZQ/z
public static void add(CountBean cb){ t(5PKD#~Dc
if(cb!=null){ Zf8_ko;|:-
list.add(cb); 6,Y<1b*|Vo
} "/$2oYNy+
} l5CFm8%
} H 5'Ke+4.e
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CountControl.java K_[B@( Xl
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/* J(=io_\bO
* CountThread.java <%:,{u6
* h4k.1yH;
* Created on 2007年1月1日, 下午4:57 K}9 c$C4
* \"?5CHz*
* To change this template, choose Tools | Options and locate the template under }(Dt,F`
* the Source Creation and Management node. Right-click the template and choose *_!}g
]
* Open. You can then make changes to the template in the Source Editor. h5VZ-v_j
*/ >):^Zs
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package com.tot.count; _jD\kg#LY
import tot.db.DBUtils; Zp
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import java.sql.*; [vyi_0[
/** _/@u[dWeL
* 5 p! rZ
* @author \ 3HB
*/ _!Ir|j.A
public class CountControl{ ;A;FR3=)
private static long lastExecuteTime=0;//上次更新时间 "vN~7%
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !ui:0_
/** Creates a new instance of CountThread */
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public CountControl() {} ><3!J+<?
public synchronized void executeUpdate(){ D:vX/mf;7
Connection conn=null; eeu;A,@U
PreparedStatement ps=null; aXRf6:\%
try{ VVDd39q
conn = DBUtils.getConnection(); oeIza<:=R
conn.setAutoCommit(false); o=y0=,:a?9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); < r7s,][&
for(int i=0;i<CountCache.list.size();i++){ o-r00H|
CountBean cb=(CountBean)CountCache.list.getFirst(); I/ V`@*/+
CountCache.list.removeFirst(); ;FO( mL (
ps.setInt(1, cb.getCountId()); N
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ps.executeUpdate();⑴ DRuG5| {I:
//ps.addBatch();⑵ O[<0\
} /YT _~q=:
//int [] counts = ps.executeBatch();⑶ ^QTtCt^:
conn.commit(); :*dfP/GO
}catch(Exception e){ { bD:OF
e.printStackTrace(); p^THoF'~T
} finally{ U3b&/z|b?
try{ }?^5L7n
if(ps!=null) { P1I L]
ps.clearParameters(); :DoE_
ps.close(); RgTrj
ps=null; o%sx(g=q6
} 'jj|bN
}catch(SQLException e){} II)
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DBUtils.closeConnection(conn); e]q(fPK
} 8m"jd+
} '4]_~?&x
public long getLast(){ HGl.dO7NU
return lastExecuteTime; =@y
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} ~zph,bk
public void run(){ o GN*p_g
long now = System.currentTimeMillis(); m*H' Cb
if ((now - lastExecuteTime) > executeSep) { l7vxTj@(-
//System.out.print("lastExecuteTime:"+lastExecuteTime); tiQeON-Q_
//System.out.print(" now:"+now+"\n"); QP:|D_k
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); W}aCU~
lastExecuteTime=now; "`Mowp*
executeUpdate(); qEajT"?
} ~x6<A\
else{ "#G`F
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g=L80$1
} (,OF<<OH
} ^g
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} $i]G'fj
//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 AtYqD<hl:
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类写好了,下面是在JSP中如下调用。 bd)'1;p
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<% ,Aw
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CountBean cb=new CountBean(); RAB'%CY4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); P]%)c6Uh
CountCache.add(cb); %=`wN^3t2
out.print(CountCache.list.size()+"<br>"); J1g+H2
CountControl c=new CountControl(); Eu|O<9U\
c.run(); S:8 WBY] M
out.print(CountCache.list.size()+"<br>"); H?cJ'Q,5
%>