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: Q_4Zb
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CountBean.java 7BFN|S_l
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/* ybvI?#
* CountData.java B\_[R'Pf&
* c8ZCs?
* Created on 2007年1月1日, 下午4:44 8H
$ #+^lW
* JTUNb'#RZ
* To change this template, choose Tools | Options and locate the template under lrys3
* the Source Creation and Management node. Right-click the template and choose Tbh '_F6
* Open. You can then make changes to the template in the Source Editor. nj2gs,k
*/ h>3H7n.
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package com.tot.count; 9<cOYY
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/** 5(J^N
* o'Y#H
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* @author "ahvNx;x
*/ Qpu3(`d<
public class CountBean { +qkMQETV6
private String countType; mJMq{6;
int countId; 0IzZKRw
/** Creates a new instance of CountData */ frH)_ YJ%
public CountBean() {} xzikD,FV
public void setCountType(String countTypes){ wk ikD
this.countType=countTypes; <t}? $1
} u!1/B4!'O
public void setCountId(int countIds){ B8~=RmWLl
this.countId=countIds; (@Zcx9
} _01Px a2.
public String getCountType(){ A3s57.Z]|
return countType; /77z\[CeYH
} #x~_`>mDN
public int getCountId(){ _^T}_
return countId; yGEb7I$h
} 9X]f [^
} D/s?i[lb
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CountCache.java ;Qa;@
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/* &O tAAE
* CountCache.java og-]tEWA1
* -1W
* Created on 2007年1月1日, 下午5:01 yXF|Sqv
* &r@H(}$1\
* To change this template, choose Tools | Options and locate the template under !Zs,-=^D
* the Source Creation and Management node. Right-click the template and choose cyMs(21
* Open. You can then make changes to the template in the Source Editor. -,GEv%6c
*/ E1W:hGI
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package com.tot.count; A,c'g}:
import java.util.*; Y:pRcO.4g
/** :_H>SR:
* Jsn <,4DO8
* @author ]kS7n@8
*/ q^Inb)FeN
public class CountCache { ]{Ek[Av
public static LinkedList list=new LinkedList(); K-4tdC3
/** Creates a new instance of CountCache */ 0QoLS|voA/
public CountCache() {} N!m%~kS9k<
public static void add(CountBean cb){ T
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if(cb!=null){ r}EM4\r
list.add(cb); uaxB -PZ
} :qnokrGzB
} 1nB@zBQu-
} sqG`"O4W
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CountControl.java /=ylQn3
*
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/* RVP 18ub.S
* CountThread.java z!CD6W1n
* -N z}DW>
* Created on 2007年1月1日, 下午4:57 AbZ:(+@cP
* :t>Q:mX(N
* To change this template, choose Tools | Options and locate the template under }17bV, t
* the Source Creation and Management node. Right-click the template and choose m!Af LSlwm
* Open. You can then make changes to the template in the Source Editor. /*P7<5n0
*/ -f.R#J$2
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package com.tot.count; &<h?''nCy
import tot.db.DBUtils; R3G@G
import java.sql.*; iQ{z6Qa
/** C BlXC7_Mi
* ;+%Z@b%
* @author if@,vc
*/ /q*KO\L
public class CountControl{ ':sTd^V
private static long lastExecuteTime=0;//上次更新时间 P)IjL&[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 b~as64
/** Creates a new instance of CountThread */ .e$%[)D
public CountControl() {} 'w6hW7"L
public synchronized void executeUpdate(){ UE7'B?
Connection conn=null; w `!LFHK
PreparedStatement ps=null; `,Zb2"
try{ g)cY\`&W8
conn = DBUtils.getConnection(); }
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conn.setAutoCommit(false); ]ym C3LV]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .K7C-Xn=
for(int i=0;i<CountCache.list.size();i++){ 6Ahr_{
CountBean cb=(CountBean)CountCache.list.getFirst(); 7TdQRB
CountCache.list.removeFirst(); 0||F`24
ps.setInt(1, cb.getCountId()); b,Lw7MY}[
ps.executeUpdate();⑴ kW(Kh0x
//ps.addBatch();⑵ A'~#9@l<
} kaO{#i2-
//int [] counts = ps.executeBatch();⑶ yoW>
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conn.commit(); 5)*6V&
}catch(Exception e){ -fPT}v
e.printStackTrace(); raHVkE{<
} finally{ -yA3 RP
try{ "Q?_ EE n
if(ps!=null) { ' =}pxyg
ps.clearParameters(); X<FOn7qf
ps.close(); Hf_'32e3<
ps=null; ^S=cNSpC
} Yj3*)k
}catch(SQLException e){} H9E(\)@
DBUtils.closeConnection(conn); 2L[l'}
} ~#t*pOC5BR
} kF2Qv.5!
public long getLast(){ j"6:A
return lastExecuteTime; >KHp-|0pv
} ,-:a?#f>
public void run(){ P57GqT
long now = System.currentTimeMillis(); m9Il\PoTq
if ((now - lastExecuteTime) > executeSep) { - p^'XL*Z
//System.out.print("lastExecuteTime:"+lastExecuteTime); P'F~\**5
//System.out.print(" now:"+now+"\n"); g8v[)o(qd
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); P4[]qbfd,
lastExecuteTime=now; `:gYXeR
executeUpdate(); yU!GS-
} {\Ys@FF
else{ @E(P9zQ/zy
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); V" }*"P-%
} 6lZGcRO
}
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} g@(4ujOT
//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 ^Rk^XQCh
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类写好了,下面是在JSP中如下调用。 ) H+d.Y
ETg{yBsp
<% HSC6;~U
CountBean cb=new CountBean(); Tplg2p%k
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `Jqf**t
CountCache.add(cb); F;W'
out.print(CountCache.list.size()+"<br>"); aPt{C3<
CountControl c=new CountControl(); N5ci};?
c.run(); a_AJ)4
out.print(CountCache.list.size()+"<br>"); /]g>#J%b
%>