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: h9tB''ePE
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CountBean.java CsJ)Z%4_
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/* iSSc5ek4
* CountData.java e{^:/WcYB
* P-/XYZ]`
* Created on 2007年1月1日, 下午4:44 stf,<W
* +a7EsR
* To change this template, choose Tools | Options and locate the template under U:s}/to
* the Source Creation and Management node. Right-click the template and choose D[?k ,*
* Open. You can then make changes to the template in the Source Editor.
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*/ Bf D,z
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package com.tot.count; OqEg{o5 a&
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/** Fw(b1 d>E
* ZXFAuF
* @author ~rVKQ-+4&
*/ &4w\6IR
public class CountBean { # i`A4D
private String countType; d,GtH)( s
int countId; [ u`17hyX
/** Creates a new instance of CountData */ *F26}q
public CountBean() {} .g6PrhzFbk
public void setCountType(String countTypes){ hqhu^.}]
this.countType=countTypes; 1qB!RIau
} T% /xti5$!
public void setCountId(int countIds){ >N+bU{s
this.countId=countIds; -13P 2<i+
} WHpUjyBP
public String getCountType(){ PK:o}IWn~x
return countType; 3p?<iVE
} 0%GqCg
public int getCountId(){ CjC'"+[w
return countId; p=mCK@
} (>!]A6^L~
} kT Z?+hx
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CountCache.java NB!'u)
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/* *zw
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* CountCache.java 2A@Y&g(6T7
* ain#_H
* Created on 2007年1月1日, 下午5:01 =Do3#Xe2V
* 7/p J6>
* To change this template, choose Tools | Options and locate the template under EPE!V>
* the Source Creation and Management node. Right-click the template and choose E3FW*UNg[y
* Open. You can then make changes to the template in the Source Editor. L|C1C
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*/ 3<e(@W}n-M
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package com.tot.count; xN{"%>Mx
import java.util.*; uu
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/** K$37}S5
* O X5Co<u
* @author zAkc67:
*/ IF36K^K
public class CountCache { [5 Y$L
public static LinkedList list=new LinkedList(); 6)uPM"cO
/** Creates a new instance of CountCache */ KG4#BY&^
public CountCache() {} g~ppPAH
public static void add(CountBean cb){ n,Yr!W:h
if(cb!=null){
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list.add(cb); 20Cie
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} oPBg+Bh*
} yKe*<\
} &(H)gjH
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CountControl.java niBjq#bJi
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/* 9QX~aX
* CountThread.java P*0nT
* [G'!`^V,
* Created on 2007年1月1日, 下午4:57 [0tfY0
* 3gPD(r1g
* To change this template, choose Tools | Options and locate the template under $p}~,Kp/
* the Source Creation and Management node. Right-click the template and choose U'Ja\Ek/f
* Open. You can then make changes to the template in the Source Editor. w$(0V$l_
*/ YvxMA#
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package com.tot.count; 3gV&`>@
import tot.db.DBUtils; ATMogxh
import java.sql.*; T je o*n^
/** |;U}'|6
* IQk#
* @author c`$`0}
*/ *1o+o$hY2
public class CountControl{ quCWc2pXX
private static long lastExecuteTime=0;//上次更新时间 >^a"Z[s[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 wEHAkc)Q
/** Creates a new instance of CountThread */ UgD'Bi
public CountControl() {} JK:mQ_
public synchronized void executeUpdate(){ mNnw G);$
Connection conn=null; qj3bt_F!x
PreparedStatement ps=null; lEYT{
try{ ~J. Fl[
conn = DBUtils.getConnection(); FVC2 XxP
conn.setAutoCommit(false); <*r<+S
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }n2-*{)x
for(int i=0;i<CountCache.list.size();i++){ IioE<wS)
CountBean cb=(CountBean)CountCache.list.getFirst(); |W~V@n8"6
CountCache.list.removeFirst(); QGbD=c7
ps.setInt(1, cb.getCountId()); f,`}hFD
ps.executeUpdate();⑴ bWQORjnd8
//ps.addBatch();⑵ '4^V4i
}
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//int [] counts = ps.executeBatch();⑶ _r?;lnWx@
conn.commit(); O)RzNfI^`N
}catch(Exception e){ JV?RgFy
e.printStackTrace(); @aiLGwh
} finally{ F~Z 0
try{ O"J.k&C<,
if(ps!=null) { H/@M
ps.clearParameters(); rlO%%Qn`
ps.close(); Dt~}9HrU
ps=null; QIMv9;
} +U_-Lq )
}catch(SQLException e){} `6BS-AVO7
DBUtils.closeConnection(conn); FbCZV3Y
} vN%j-'D\A4
} 'j"N2NJ
public long getLast(){ P8,{k
return lastExecuteTime; !k>H e*M}P
} Lx:N!RDw
public void run(){ J?Ep Nie
long now = System.currentTimeMillis(); VG'(
if ((now - lastExecuteTime) > executeSep) { wx"6",M
//System.out.print("lastExecuteTime:"+lastExecuteTime); CN$A-sjZ
//System.out.print(" now:"+now+"\n"); (E1>}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); @Y&9S)xcE
lastExecuteTime=now; ad$Qs3)6o
executeUpdate(); P15* VPy
} *liPJ29C[
else{ 0h@%q;g
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); a]wcA
} 55\X\>
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} _6-/S!7Y\
} *UL|{_)c
//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 'y M:WcN
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类写好了,下面是在JSP中如下调用。 ;~Gpw/]5E
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<% U)w|GrxX
CountBean cb=new CountBean(); >'|xQjLl
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /L|}Y242
CountCache.add(cb); BL5
out.print(CountCache.list.size()+"<br>"); 5WNg+
CountControl c=new CountControl(); vBn=bb'W
c.run(); (&]15 FJ$1
out.print(CountCache.list.size()+"<br>"); &G,o guo
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