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: @r GY9%E
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CountBean.java DdR0u0JH0
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/* $OZ= L
* CountData.java gKb,Vrt
* bSe\d~{
* Created on 2007年1月1日, 下午4:44 q(n"r0)=
* !=YE hQ-
* To change this template, choose Tools | Options and locate the template under ?|ZbQz(bL
* the Source Creation and Management node. Right-click the template and choose ]Za[]E8MD
* Open. You can then make changes to the template in the Source Editor. 3jZGO9ttnS
*/ iZNS? ^U
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package com.tot.count; :)lS9<Y}
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/** =2$(
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* C_J@:HlJ
* @author |Ahf 01
*/ kN/YnY*J<
public class CountBean { ,=+t2Bn
private String countType; uB)q1QQsqp
int countId; `t/j6e]
/** Creates a new instance of CountData */ e 6mZ;y5_
public CountBean() {} r|l?2 eO~
public void setCountType(String countTypes){ O[d#-0s
this.countType=countTypes; 1%_RXQVG
} EK# 11@0%
public void setCountId(int countIds){ Phi5;U!
this.countId=countIds; QD7KE6KP'
} 4`8s]X
public String getCountType(){ M0$MK>
return countType; n$2oM5<
} WK$\#>T
public int getCountId(){ /0\g!29l<
return countId; ~u%$ 9IhM
} 3zB'AG3b
} ]$ d ;P
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CountCache.java 1Le8W)J
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/* i+14!LlI
* CountCache.java t"B3?<?]
* 8-@@QZ\N
* Created on 2007年1月1日, 下午5:01 YC1Bgz
* A O5&Y.A#
* To change this template, choose Tools | Options and locate the template under |tAkv
* the Source Creation and Management node. Right-click the template and choose ) p>Cf_[.
* Open. You can then make changes to the template in the Source Editor. s4|tWfZ
*/ 9`Qa/Y!
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package com.tot.count; 8gavcsVE[
import java.util.*; PE5*]+lW.
/** .F,l>wUNe
* DinZZ
* @author &.E/%pQ`
*/ lG-B)
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public class CountCache { <}lah%4F
public static LinkedList list=new LinkedList(); [2,D] e
/** Creates a new instance of CountCache */ #HV5M1mb
public CountCache() {} H5 z1_O_+
public static void add(CountBean cb){ X{ x(p
if(cb!=null){ ;h1hz^Wq
list.add(cb); Tz)Ku
} ,marNG
} :,l16{^
} ZV--d'YiEm
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CountControl.java E#_/#J]UQn
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/* "_&ZRcd*
* CountThread.java bit|L7*14
* /Pextj<
* Created on 2007年1月1日, 下午4:57 E0I/]0
* Ug+ K:YUq
* To change this template, choose Tools | Options and locate the template under $ ,K@xq5
* the Source Creation and Management node. Right-click the template and choose rG?5z"
* Open. You can then make changes to the template in the Source Editor. q;#AlquY @
*/ I8! .n
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package com.tot.count; ?lkB{-%rQ
import tot.db.DBUtils; @2T8H
import java.sql.*; EPJ>@A>;D
/** `V9bd}M%~;
* H<|}pZ
* @author S"*k#ao
*/ j1`<+YT<#
public class CountControl{ `^Ll@Cx"
private static long lastExecuteTime=0;//上次更新时间 %l8!p'a
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 LBq2({="
/** Creates a new instance of CountThread */ ftpPrtaP
public CountControl() {} z00X
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public synchronized void executeUpdate(){ ~IYR&GEaUG
Connection conn=null; VHPqEaR
PreparedStatement ps=null; eGT&&Y
try{ kBqgz|jE%
conn = DBUtils.getConnection(); ^1~lnD~0
conn.setAutoCommit(false); b_`h2dUq
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); kcUn GiP
for(int i=0;i<CountCache.list.size();i++){ k.b=EX|
CountBean cb=(CountBean)CountCache.list.getFirst(); &OJ?Za@p@)
CountCache.list.removeFirst(); vLxaZWr
ps.setInt(1, cb.getCountId()); 1Du5Z9AM
ps.executeUpdate();⑴ "Bwz
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//ps.addBatch();⑵ 4!Radl3`
} &Z>??|f
//int [] counts = ps.executeBatch();⑶ \)5mO 8w
conn.commit(); aAe`o2Xs
}catch(Exception e){ <.Zh{"$qo
e.printStackTrace(); OK v2..8
} finally{ w2xD1oK~o
try{ 5wW5
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if(ps!=null) { Sed8Q-m
ps.clearParameters(); Ej)7[
ps.close(); L{VnsY V
ps=null; 4L:O0Ggz}
} ~S<aIk0l
}catch(SQLException e){} p@O Ip
DBUtils.closeConnection(conn); omg#[
} 4
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} QOK,-
public long getLast(){ c
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return lastExecuteTime; E[#VWM
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} ]&H"EHC<$
public void run(){ OD7^*j(p`
long now = System.currentTimeMillis(); I'BHNZO5tf
if ((now - lastExecuteTime) > executeSep) { TrzAgNt
//System.out.print("lastExecuteTime:"+lastExecuteTime); va_u4
//System.out.print(" now:"+now+"\n"); /ojx$Um
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); qCI7)L`
lastExecuteTime=now; Mi#i 3y(
executeUpdate(); lr4wz(q<9
} 7_PY%4T"
else{ zWU]4;,"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Uhr2"Nuuy
} $)@D(m,ybd
} %\-E
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} b>QdP$>
//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 )NhC+=N
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类写好了,下面是在JSP中如下调用。 5.ab/uk;M
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<% Dqo#+_v
CountBean cb=new CountBean(); X+sKG5nS
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); m5
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CountCache.add(cb); bK!h{Rr
out.print(CountCache.list.size()+"<br>"); C_>XtcU
CountControl c=new CountControl(); oh:9v+
c.run(); ~tWh6-:|{J
out.print(CountCache.list.size()+"<br>"); c_ncx|dUs
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