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: 5lKJll^2:
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CountBean.java m4k
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/* ?71+f{s
* CountData.java (%CZ*L[9Z
* Ph&urxH@
* Created on 2007年1月1日, 下午4:44 P27%xV-n>
* T[k4lM
* To change this template, choose Tools | Options and locate the template under C;AA/4Ib
* the Source Creation and Management node. Right-click the template and choose _s,ao'/
* Open. You can then make changes to the template in the Source Editor. wo2@hav
*/ `i,_aFB|
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package com.tot.count; ?B@;QjhjiJ
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/** P47V:E%
* @ufo$?D
* @author 9DQ)cy
*/ TjWE_Bq]g
public class CountBean { DVZdClAL
private String countType; >!e<}84b
int countId; c97{Pu
/** Creates a new instance of CountData */ uaw~r2
public CountBean() {} o!TQk{0
public void setCountType(String countTypes){ dCYCHHHF
this.countType=countTypes; Zt
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} + Y.1)i}
public void setCountId(int countIds){ _R|Ify#J
this.countId=countIds; B@Co'DV[/]
} @r(Z%j7
public String getCountType(){ I-D^>\k+
return countType; :6 J +%(f
} i>L+gLW
public int getCountId(){ Uk*IpP`
return countId; p Y)5bSA
} aIy*pmpD=
} kB:Uu}(=N
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CountCache.java HysS_/t~
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/* }TRAw#h
* CountCache.java F~#zxwd
* 6dH }]~a
* Created on 2007年1月1日, 下午5:01 h!@|RW&}qX
* <^.=>Q0S\
* To change this template, choose Tools | Options and locate the template under }_tl n
* the Source Creation and Management node. Right-click the template and choose `cz2DR-"
* Open. You can then make changes to the template in the Source Editor. KAA-G2%M
*/ n>3U_yt6b
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package com.tot.count; ^{$FI`P
import java.util.*; F+ <Z<q
/** MiT}L
* v dbO(
* @author .9*wY0:
*/ -hcS]~F
public class CountCache { ] G.%Ty
public static LinkedList list=new LinkedList(); ',3HlOJ:
/** Creates a new instance of CountCache */ gwrYLZNGI
public CountCache() {} p;)"
public static void add(CountBean cb){ %)jxW{
if(cb!=null){ 2I3h
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list.add(cb); \?>Hu
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} @53k8
} 'X).y1'
} U/ V
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CountControl.java [%~
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/* X5fmz%VK@
* CountThread.java HjvCujJ
* ~I/@i
* Created on 2007年1月1日, 下午4:57 M}:=zcZ l
* +;BAV
* To change this template, choose Tools | Options and locate the template under j hYToMq
* the Source Creation and Management node. Right-click the template and choose _LP/!D
* Open. You can then make changes to the template in the Source Editor. X)SDG#&+bF
*/ 3P~o"a>
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package com.tot.count; (@X~VACT
import tot.db.DBUtils; Wc3kO'J
import java.sql.*; fy@avo9
/** Xdi:1wW@p
* B!{d-gb
* @author (Q[fS:U
*/ 76tdJ!4Z
public class CountControl{ \y6OUM2y
private static long lastExecuteTime=0;//上次更新时间 /[:dp<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #Lsnr.80
/** Creates a new instance of CountThread */ O1%pxX'`S
public CountControl() {} !Bz0^1,L
public synchronized void executeUpdate(){ U<"WK"SM
Connection conn=null; gK#mPcn^
PreparedStatement ps=null; EcIE~qs
try{ t$2_xX
conn = DBUtils.getConnection(); K]/4qH$:
conn.setAutoCommit(false); )m6M9eC
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @uo ~nF j,
for(int i=0;i<CountCache.list.size();i++){ Yw5' 6NU
CountBean cb=(CountBean)CountCache.list.getFirst(); -yxOBq
CountCache.list.removeFirst(); ~pa!w?/bQ
ps.setInt(1, cb.getCountId()); IJTtqo
ps.executeUpdate();⑴ i'd2[A.7I
//ps.addBatch();⑵ $,I q;*7N
} R [H+qr
//int [] counts = ps.executeBatch();⑶ s}5cSU!|
conn.commit(); !$2Z-!
}catch(Exception e){ $'W}aER
e.printStackTrace(); &aM7T_h8
} finally{ GdB.4s^
try{ _'4A|-9
if(ps!=null) { NmK8<9`u
ps.clearParameters(); wB'zuPAK6
ps.close(); 6nhMP$h
ps=null; d]9U^iy
} \
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}catch(SQLException e){} sGvIXD
DBUtils.closeConnection(conn); 2|\A7.
} (R`B'OtGg
} r&-m=Kk$
public long getLast(){ 9a'-Y
return lastExecuteTime; Uax+dl
} fEB7j-t
public void run(){ (E,T#uc{
long now = System.currentTimeMillis(); Vcd.mE(t%
if ((now - lastExecuteTime) > executeSep) { .4.b*5
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5cx#SD&5/
//System.out.print(" now:"+now+"\n"); }@if6(0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Qf@I)4'
lastExecuteTime=now; u3Gjg{-N7
executeUpdate(); $R<Me
} nRd)++
else{ .q+0pj
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); zByT$P-
} ceNix!P
} B^).BQ
} aq7~QX_0G
//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 "3FihE]k
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类写好了,下面是在JSP中如下调用。 5SCKP<rb
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<% L(GjZAP
CountBean cb=new CountBean(); j*xV!DqC
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); c8Z wr]DF
CountCache.add(cb); vb9OonE2
out.print(CountCache.list.size()+"<br>"); E2)h?cs
CountControl c=new CountControl(); x8GJY~:SW
c.run(); -OSa>-bzNx
out.print(CountCache.list.size()+"<br>"); 2Sm}On
%>