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: hp!d/X=J_
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CountBean.java `linG1mF
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/* MlO-+}`_+
* CountData.java tgFJZA
* SDJH;c0
* Created on 2007年1月1日, 下午4:44 E,G<_40
* dFW=9ru+MQ
* To change this template, choose Tools | Options and locate the template under IxSV? k
* the Source Creation and Management node. Right-click the template and choose S*W;%J5
* Open. You can then make changes to the template in the Source Editor. -mNQ;zI1
*/ To"dG&h
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package com.tot.count; +`en{$%%
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/** SQ(apc}N4
* Ng<1Sd|MV
* @author _uH9XGm
*/ '8`T|2
public class CountBean { r((Tavn
private String countType; j\)H
int countId; $N+6h#
/** Creates a new instance of CountData */ 9w~cvlv[
public CountBean() {} 2=*=^)FNI
public void setCountType(String countTypes){ e$l6gY
this.countType=countTypes; =v-2@=NJ`K
} cf8-]G?tK
public void setCountId(int countIds){ q=c/B(II!
this.countId=countIds; Ub)I66
} :iCM=k
public String getCountType(){ 6vz1*\:H~
return countType; m@qqVRn#)
} (i`(>I.(/
public int getCountId(){ is#8R:7.:
return countId; Hhv$4;&X
} Cw1(5
} Lyoor1
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CountCache.java hw,^G5m
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/* *3Nn +T
* CountCache.java UmP'L!
* xfHyC'?
* Created on 2007年1月1日, 下午5:01 l8wF0|
* 'Ji+c
* To change this template, choose Tools | Options and locate the template under ,seFkG@1
* the Source Creation and Management node. Right-click the template and choose xPQL?.
* Open. You can then make changes to the template in the Source Editor. 0-xCp ~vE
*/ =MSu3<y,
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package com.tot.count; :c4kBl%gJ
import java.util.*; HHS45kg[c
/**
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* h5onRa*7
* @author )!-S|s'
*/ |~$7X
public class CountCache { ,IjdO(?TC
public static LinkedList list=new LinkedList(); Nlt4)
/** Creates a new instance of CountCache */ |9s wZ[
public CountCache() {} &5q{viI
public static void add(CountBean cb){ 4
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if(cb!=null){ `"Dy%&U
list.add(cb); T-P@u-DU
} L>nO:`>h
} 2LhE]O(_"
} BX$hAQ(6Q
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CountControl.java "6V_/u5M;=
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/* |h,FUj<r
* CountThread.java 3wNN<R
* ZjD2u8e
* Created on 2007年1月1日, 下午4:57 Yq;&F0paK
* `@$YlFOW
* To change this template, choose Tools | Options and locate the template under M(S{1|,V
* the Source Creation and Management node. Right-click the template and choose lIl9ypikg
* Open. You can then make changes to the template in the Source Editor. VRhRwdC
*/ s5.k|!K
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package com.tot.count; <4NQL*|>
import tot.db.DBUtils; $K=z
import java.sql.*; ^'Zh;WjI7
/** h.LSMU (O
* j?J=w=.Nx
* @author L&HzN{K
*/ N[{]iQ
public class CountControl{ q_58Lw
private static long lastExecuteTime=0;//上次更新时间 h>Rpb#]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !L$oAqW
/** Creates a new instance of CountThread */ j)@oRWL<
public CountControl() {} ~$ WQ"~z
public synchronized void executeUpdate(){ @}{VM)Fc+
Connection conn=null; bgXc_>T6_y
PreparedStatement ps=null; ]eL~L_[G\
try{ ^ N_`^m
conn = DBUtils.getConnection(); h=mv9=x
conn.setAutoCommit(false); @f'AWeJ2
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); OAyE/Q|
for(int i=0;i<CountCache.list.size();i++){ ,,2_/u\"/i
CountBean cb=(CountBean)CountCache.list.getFirst(); Ua!Odju*w
CountCache.list.removeFirst(); Ot"(uW4$[
ps.setInt(1, cb.getCountId()); "lb\c
ps.executeUpdate();⑴ ,dq`EsHg`M
//ps.addBatch();⑵ LQ|<3]
} ,DQ
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//int [] counts = ps.executeBatch();⑶ '.xkn{c
conn.commit(); yl|R:/2V
}catch(Exception e){ Pyit87h{
e.printStackTrace(); vV2o[\o^
} finally{ DwQp$l'NfW
try{ |c
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if(ps!=null) { ec,z6v^9
ps.clearParameters(); !vi4*
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ps.close(); <4S F~i
ps=null; e1Dj0s?i~K
} ">0 /8] l
}catch(SQLException e){} 8Na}Wp;|Gi
DBUtils.closeConnection(conn); y0lL Fe~
} ZO]E@?Oav
} NF@i#:
public long getLast(){ $4&8U ~Zs
return lastExecuteTime; C5d/)aC
} E%KC'TN^D
public void run(){ d;IJ0xB+by
long now = System.currentTimeMillis(); 6!i(
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if ((now - lastExecuteTime) > executeSep) { ..sJtA8
//System.out.print("lastExecuteTime:"+lastExecuteTime); K4BTk!
//System.out.print(" now:"+now+"\n"); DWHOSXA4
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); h:eN>yW
lastExecuteTime=now; #p;4:IT
executeUpdate(); 99=[>Ck)G
} |8b$x| B
else{ X:iG[iU*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); OsDp88Bc
} jTGS6{E
} n/,rn>k7:
} N GX-'w
//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 f[wjur
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类写好了,下面是在JSP中如下调用。 i|::vl
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<% T(t
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CountBean cb=new CountBean(); 50O7=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); j@!BOL~?
CountCache.add(cb); O#<|[Dzw
out.print(CountCache.list.size()+"<br>"); u k>q\j
CountControl c=new CountControl(); U:C-\ M
c.run(); @Wlwt+;fT
out.print(CountCache.list.size()+"<br>"); 10a=YG
%>