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: X8x>oV;8
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CountBean.java *$$V,6O.
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/* pb
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* CountData.java o?FUVK
* <Y2!c,"
* Created on 2007年1月1日, 下午4:44 fLoVcl
* ] O>7x
* To change this template, choose Tools | Options and locate the template under A%2}?Ds
* the Source Creation and Management node. Right-click the template and choose uCfp+
* Open. You can then make changes to the template in the Source Editor. ;/T-rVND
*/ j2M(W/_
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package com.tot.count; 6w;|-/:`
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/** OF/)-}!
* q)b?X
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* @author >pvg0Fh
*/ >NA7,Z2.
public class CountBean { NF!1)
private String countType; +:%FJCOT
int countId; K>6k@okO
/** Creates a new instance of CountData */ s*~o%emw
public CountBean() {} tlgvBRH>
public void setCountType(String countTypes){ "'B%.a#k
this.countType=countTypes; Sg>0P*K@
} !y~b;>887
public void setCountId(int countIds){ j]"xck
this.countId=countIds; 5qSZ>DZ
} 9nS!
public String getCountType(){ %:?QE
;
return countType; xN8JrZE&
} Jk`)`94I
public int getCountId(){ !gHWYWu)!
return countId; :[f`HY&
} =Zy!',,d,9
} ><R.z(4%
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CountCache.java H<}eoU.
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/* ld}$Tsy0
* CountCache.java A i){,nh`0
* >wO$Vu
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* Created on 2007年1月1日, 下午5:01 ]GPJ(+5
* _i@eOqoC
* To change this template, choose Tools | Options and locate the template under B~zg"
* the Source Creation and Management node. Right-click the template and choose =L),V~b
* Open. You can then make changes to the template in the Source Editor. qU*&49X
*/ ]\,uF8gg)
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package com.tot.count; {FY[|:Cp
import java.util.*; 2\B9o `Y
/** A=d$ir
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* 6H,=S`V]EK
* @author /JubiLEK
*/ :;;WK~*#
public class CountCache { $YY)g$
public static LinkedList list=new LinkedList(); X/K)kIi
/** Creates a new instance of CountCache */ 'Sy *'&
public CountCache() {} -Dxhq&
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public static void add(CountBean cb){ I''R\Bp
if(cb!=null){ /
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list.add(cb); \R\@t]>Y
} L2.`1Aag
} .`>l.gmi&
} Ij}F<ZgZG
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CountControl.java TT ZxkK
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/* (2bZ]
* CountThread.java !aw#',r8m
* N^(lUba
* Created on 2007年1月1日, 下午4:57 #lsh N,CPm
* I
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* To change this template, choose Tools | Options and locate the template under h`h>H
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* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. 0O,T=z[+>
*/ oA;Ty7s
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package com.tot.count; W({TC
import tot.db.DBUtils; j-`X_8W
import java.sql.*; ~J>gVg%66
/** =Cy>$/H64
* tK|9qs<%
* @author t)gi.Ed1"L
*/ yC 7Vb
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public class CountControl{ Ryba[Fz4Di
private static long lastExecuteTime=0;//上次更新时间 3E!<p
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 "R2t&X[9
/** Creates a new instance of CountThread */ DxKfWb5 R
public CountControl() {} w-H%B`/
public synchronized void executeUpdate(){ LX\*4[0%K
Connection conn=null; xJ2O4ob
PreparedStatement ps=null; ,)rZAI
try{ ezr\T
conn = DBUtils.getConnection(); l P$r
conn.setAutoCommit(false); 8\)U|/A7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); iQ|,&K0d]
for(int i=0;i<CountCache.list.size();i++){ Zp(=[n5
CountBean cb=(CountBean)CountCache.list.getFirst(); P A6KX5
CountCache.list.removeFirst(); CI!Eq&D,
ps.setInt(1, cb.getCountId()); N`<4:v[P
ps.executeUpdate();⑴ Vvyrty
//ps.addBatch();⑵ 33<fN:J]f
} e@:P2(WWl
//int [] counts = ps.executeBatch();⑶ ?l,
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conn.commit(); qH
h'l;.
}catch(Exception e){ 0i*'N ch#i
e.printStackTrace(); w~$c= JO#
} finally{ S@}B:}2
try{ ~S^X"8(U
if(ps!=null) { `o_fUOe8a
ps.clearParameters(); c/=y*2,zo
ps.close(); Y0PGT5].@'
ps=null; E +Ujpd
} OS"{"P
}catch(SQLException e){} ^s2m\Q(
DBUtils.closeConnection(conn); _[TH@fO6:
} 'o/N}E!Pt
} [EmOA.6
public long getLast(){ 1J-Qh<Q
return lastExecuteTime; C'-zh\a
} OHHNWg_5
public void run(){ ," C[Qg(
long now = System.currentTimeMillis(); y^X\^Kq
if ((now - lastExecuteTime) > executeSep) { XJmFJafQD
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,ykPQzO
//System.out.print(" now:"+now+"\n"); uS,p|}Q&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1c)\
lastExecuteTime=now; %Ui{=920
executeUpdate(); %wt2F-u
} A \MfF
else{ ` /I bWu
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !f\?c7
} Gpdv]SON{
} dNUR)X#e
} vXyuEEe
//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 &\1'1`N1
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类写好了,下面是在JSP中如下调用。 0~+NB-L}
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<% 1m>^{u
CountBean cb=new CountBean(); |oe!P}u
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <AI>8j6#B
CountCache.add(cb); TsaW5ho<p
out.print(CountCache.list.size()+"<br>"); g> ~cs_N@
CountControl c=new CountControl(); (VYR!(17
c.run(); DO&+=o`"
out.print(CountCache.list.size()+"<br>"); 83KfM!w
%>