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: StU 4{
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CountBean.java _8Nw D_"
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/* M3Khc#5S(
* CountData.java P+dA~2k
* Y=vVxVI\
* Created on 2007年1月1日, 下午4:44 B;Xoa,
* ItI0x
* To change this template, choose Tools | Options and locate the template under t7w-TJvP
* the Source Creation and Management node. Right-click the template and choose ~u /aOd
* Open. You can then make changes to the template in the Source Editor. q=6Cc9FN
*/ yo\N[h7
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package com.tot.count; b
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/** DX}B0B
* TGU:(J'^
* @author 4\LZD{
*/ rv9B}%e
public class CountBean { #NvQmz?J?
private String countType; bTLMd$
int countId; FXP6zHsV
/** Creates a new instance of CountData */ b?_e+:\UV
public CountBean() {} {=UFk-$=
public void setCountType(String countTypes){ h+,'B&=|_
this.countType=countTypes; d_Q*$Iz)3
} #zON_[+s9
public void setCountId(int countIds){ 0QMTIAW6h
this.countId=countIds; d<Ggw#}:m
} C:`;d&d
public String getCountType(){ O:
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return countType; v(DwU!
} I eG=J4:*
public int getCountId(){ yND"bF9
return countId; %35L=d[
} '_:(oAi,C
} B*\$
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CountCache.java w8O" =},
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/* AXwaVLEBQ
* CountCache.java NS`07 #z^
* n( g)UNx
* Created on 2007年1月1日, 下午5:01 T~BA)![
* [SVhtrx|%
* To change this template, choose Tools | Options and locate the template under )4l>XlQ&
* the Source Creation and Management node. Right-click the template and choose '|A|vCRCG
* Open. You can then make changes to the template in the Source Editor. E2@`d6
*/ ^+ZgWS^%
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package com.tot.count; A)tP()+)
import java.util.*; w|IjQ1{
/** ! Tx&vtq
* 2{bhA5L
* @author bS.s?a
*/ 33Jd!orXU
public class CountCache { JVtQ,oZ
public static LinkedList list=new LinkedList(); =#qZ3 Qz_
/** Creates a new instance of CountCache */ L!t@-5~
public CountCache() {} "~F3*lk#E
public static void add(CountBean cb){ <5S@ORN
if(cb!=null){ k<a;[_S
list.add(cb); .evbE O 5
} |EKu2We*
} E<tK4?i"
} 0RUi\X4HI
!b8uLjd;
CountControl.java YEv%C|l
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/* -$(Jk<
* CountThread.java jMM$ d,7B
* E@-ta):
* Created on 2007年1月1日, 下午4:57 bLzs?eos
* Mi+H#xx16
* To change this template, choose Tools | Options and locate the template under 0Vkl`DmeM.
* the Source Creation and Management node. Right-click the template and choose ~ 3^='o
* Open. You can then make changes to the template in the Source Editor. ]hA,LY f
*/ LxLy+yC#p
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package com.tot.count; +oI3I~
import tot.db.DBUtils; F]UQuOR)
import java.sql.*; %SrM|&[
/** j9d!yW
* >I}9LyZt
* @author xl(@C*.sC1
*/ `ltN,?/
public class CountControl{ <Mx0\b!
private static long lastExecuteTime=0;//上次更新时间 [}OgSP9i
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :_ROJ
/** Creates a new instance of CountThread */ %f j+70
public CountControl() {} {%C*{,#+8q
public synchronized void executeUpdate(){ G?AG:%H %
Connection conn=null; [U>@,BH
PreparedStatement ps=null; K=dR%c(
try{ `0ZZ/]
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conn = DBUtils.getConnection(); K*q[(,9
conn.setAutoCommit(false); .Da'pOe
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); S${Zzt"
for(int i=0;i<CountCache.list.size();i++){ 7Ym(n8
CountBean cb=(CountBean)CountCache.list.getFirst(); oRM)%N#
CountCache.list.removeFirst(); Yw'NX5#)g
ps.setInt(1, cb.getCountId()); *4S-z&,.c
ps.executeUpdate();⑴ qnM|w~G
//ps.addBatch();⑵ :`\)
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} J NVr
//int [] counts = ps.executeBatch();⑶ :u6JjW[a)
conn.commit(); !z 53OT!
}catch(Exception e){ k|vI<:'p,
e.printStackTrace(); iDoDwq!l_
} finally{ #*9-d/K
try{ ?YQPlv:<o.
if(ps!=null) { a,|?5j9,P
ps.clearParameters(); ?m7:if+y
ps.close(); ujFzJdp3k
ps=null; s&a1y~rv
} Aw5pd7qKL
}catch(SQLException e){} a(IY\q[Wh
DBUtils.closeConnection(conn); *T`-|H*6@
} SJ?6{2^
} !345 %,
public long getLast(){ p5\]5bb
return lastExecuteTime; D}3T|N
} UlcH%pxTt1
public void run(){ GsQ*4=C
long now = System.currentTimeMillis(); T!RT<&
if ((now - lastExecuteTime) > executeSep) { 1PH:\0}
//System.out.print("lastExecuteTime:"+lastExecuteTime); g7\,{Bw#E
//System.out.print(" now:"+now+"\n"); ?S
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); q%(EYM5Y
lastExecuteTime=now; dY7'OAUyVl
executeUpdate(); )+P]Vf\jH
} aE"[5*a
else{ G{Yz8]m
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 3S*AxAeg
} y [#pC<^
} =<}<Ny
} K+*Q@R D
//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 6$U]9D
/./"x~@
类写好了,下面是在JSP中如下调用。 [AU
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<% i;/xK=L
CountBean cb=new CountBean(); g.py+
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [XVEBA4GI
CountCache.add(cb); QaIjLc~W
out.print(CountCache.list.size()+"<br>"); Fd]\txOXj
CountControl c=new CountControl(); B* kcNlW
c.run(); P{OAV+cG
out.print(CountCache.list.size()+"<br>"); T9W`?A
%>