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: 2Rc'1sCth-
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CountBean.java )p&FDK#ob=
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/* NJG-~w
* CountData.java A#gmKS<J/7
* 7u"t4Or
* Created on 2007年1月1日, 下午4:44 e~C^*w L
* 9Z,vpTE
* To change this template, choose Tools | Options and locate the template under !\Y85o>JU
* the Source Creation and Management node. Right-click the template and choose N:j"W,8
* Open. You can then make changes to the template in the Source Editor. rzH*| B0g
*/ 5eI3a!E]O
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package com.tot.count; ^mLZT*
!@9Vq6
/** d&:ABI
* N5$L),?\y
* @author ?u/Uov@rD
*/ fKzOt<wm
public class CountBean { [:x^ffs
private String countType; gdupG
int countId; >5{Z'UWxh
/** Creates a new instance of CountData */ lHBk&UN'
public CountBean() {} >y C1X|d~t
public void setCountType(String countTypes){ +$KUy>
this.countType=countTypes; Np4';H
} G 3HmLz
public void setCountId(int countIds){ DBuvbq-
this.countId=countIds; KJPCO0"
} @B;2z_Y!l
public String getCountType(){ Bb^CukS:
return countType; 6b9 oSY-8
} `+[e]dH
public int getCountId(){ -iu7/4!j
return countId; ]de'v
} #<V/lPz+
} WQ/H8rOs
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CountCache.java &?m|PK) I
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/* @!0@f'}e
* CountCache.java fcd\{1#u
* eRkvNI
* Created on 2007年1月1日, 下午5:01 [:-Ltfr
* pp$WM\r
* To change this template, choose Tools | Options and locate the template under 5;wA7@
* the Source Creation and Management node. Right-click the template and choose !424K-nW
* Open. You can then make changes to the template in the Source Editor. ^nu~q+:+#
*/ 0?} ),8v>
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package com.tot.count; q@K;u[zFK
import java.util.*; rPoPs@CBD
/** %xtTh]s
* a?bSMt}
* @author }W{rDc kv
*/ ^z#'o
public class CountCache { 413,O~^
public static LinkedList list=new LinkedList(); V!#+Ti/w4
/** Creates a new instance of CountCache */ )UA$."~O
public CountCache() {} 1|)l6#hOL
public static void add(CountBean cb){ %|L+~ =
if(cb!=null){ B#RwW,
list.add(cb); 7%C6hEP/*W
} <aJdm!6
} zr~hGhfq
} '_& Xemz
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CountControl.java /t=R~BJu
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/* uK6`3lCD
* CountThread.java xc[LbaBG
* pPt7M'uL"
* Created on 2007年1月1日, 下午4:57 _5'OQ'P2
* g4,>cqRkq
* To change this template, choose Tools | Options and locate the template under (uV~1
* the Source Creation and Management node. Right-click the template and choose U4]>8L
* Open. You can then make changes to the template in the Source Editor. + yX\!H"
*/ fHTqLYd-
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package com.tot.count; >S4klW=*I
import tot.db.DBUtils; x/*ndH
import java.sql.*; +b_g,RNs!
/** ?bwF$Ku
* ?I{pv4G:
* @author ]O'dwC
*/ H^cB?i
public class CountControl{ <rd7<@>5D
private static long lastExecuteTime=0;//上次更新时间 i$HA@S
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 P6,~0v(S
/** Creates a new instance of CountThread */ ~|+!xh
public CountControl() {} } LLnJl~Z
public synchronized void executeUpdate(){ b0
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Connection conn=null; ))"J
PreparedStatement ps=null; s[h& Uv"G
try{ F(*~[*Ff
conn = DBUtils.getConnection(); 9U1cH qV
conn.setAutoCommit(false); |:_WdU"Q]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 16"eyt>
for(int i=0;i<CountCache.list.size();i++){ ]Igd<
CountBean cb=(CountBean)CountCache.list.getFirst(); *sI`+4h[
CountCache.list.removeFirst(); 8x$BbK
ps.setInt(1, cb.getCountId()); \ FW{&X9a
ps.executeUpdate();⑴ 0{bGVLp
//ps.addBatch();⑵ '`g#Zo
} b|F_]i T
//int [] counts = ps.executeBatch();⑶ \DsP'-t
conn.commit(); .]+Z<5Fo
}catch(Exception e){ !yAg!V
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e.printStackTrace(); 5 _X|U*+5
} finally{ {=Y%=^! s
try{ d<mj=V@bd
if(ps!=null) { Bbuy
y
ps.clearParameters(); ^c?2n
ps.close(); w'[lIEP 2$
ps=null; ]$ [J_f*x
} _^cDB1I?
}catch(SQLException e){} 49b#$Xq
DBUtils.closeConnection(conn); &|( 'z\k
} n(^{s5 Rr
} :G$f)NMK
public long getLast(){ =!{7ZSu\
return lastExecuteTime; FG.MV-G
} jt|e?1:vF
public void run(){ $_s"16s
long now = System.currentTimeMillis(); l
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if ((now - lastExecuteTime) > executeSep) { k(|D0%#b7
//System.out.print("lastExecuteTime:"+lastExecuteTime); 69{^Vfd;Y
//System.out.print(" now:"+now+"\n"); 1U[8OM{$
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); k.nq,
lastExecuteTime=now; u,i~,M
executeUpdate(); ud]O'@G<
} FHpS ?htRy
else{ j:'sbU
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g.-{=kZ
} QixEMX4<
} _@I<H\^
} F9rxm
//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 ssbvuTr
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类写好了,下面是在JSP中如下调用。 4DY\QvW5
((i%h^tGa;
<% +4G]!tV6
CountBean cb=new CountBean(); 8[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;Awt: jF
CountCache.add(cb); 5B3S]@%
out.print(CountCache.list.size()+"<br>"); 3 @XkO
CountControl c=new CountControl(); ! 6yoD
c.run(); 6gz
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out.print(CountCache.list.size()+"<br>"); .&O}/B
%>