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: sJm v{wM
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CountBean.java ){4$oXQ
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/* :-cqC|Y
* CountData.java E{[>j'dwc
* cp4~`X
* Created on 2007年1月1日, 下午4:44 {"\pMY'7
* 3SI%>CO}
* To change this template, choose Tools | Options and locate the template under __)"-\w-_(
* the Source Creation and Management node. Right-click the template and choose 9&1$\ZH
* Open. You can then make changes to the template in the Source Editor. xhncQhf\
*/ gg$:U
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package com.tot.count; 1c:/c|shQ_
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/** "2`/mtMon
* z#+Sf.
* @author $2$jV1s
*/ +(oExp(!
public class CountBean { 10m`LG
private String countType; ! Y'~?BI
int countId; |S3wCG
/** Creates a new instance of CountData */ D1cnf"y^
public CountBean() {} pwo @
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public void setCountType(String countTypes){ n/+G^:~_
this.countType=countTypes; ^1X
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} f&C]}P
public void setCountId(int countIds){ K]ds2Kp&
this.countId=countIds; >;~ ia3
} #6nuiSF
public String getCountType(){ I<hMS6$<LE
return countType; 29f4[V X
} FK;2u$:
public int getCountId(){ ePTN^#|W
return countId; l!%V&HJV
} i
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} FyRr/0C>
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CountCache.java S|T*-?|
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/* Fj1'z5$
* CountCache.java ?wMS[Kj
* iLf*m~Q
* Created on 2007年1月1日, 下午5:01 Tnb5tHjnh
* i/F].Sag
* To change this template, choose Tools | Options and locate the template under =[`gfw
* the Source Creation and Management node. Right-click the template and choose QE`u~
* Open. You can then make changes to the template in the Source Editor. ~{[,0,lWU
*/ &p.7SPQ8/
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package com.tot.count; 4,:)%KB"V
import java.util.*; VBe&of+
/** tj[-|h
* xd]7?L@h.I
* @author N-}|!pqb
*/ Z^GXKOeq
public class CountCache { P@Av/r
public static LinkedList list=new LinkedList(); D~@lpcI
/** Creates a new instance of CountCache */ %QX"oRMn0
public CountCache() {} opqf)C
public static void add(CountBean cb){ 0Y/k/)Ul]
if(cb!=null){ 0<]]q[pr
list.add(cb); ^-7-jZ@jz
} wO"ezQ
} AI3\eH+
}
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CountControl.java sW!MV v
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/* @gihIysf
* CountThread.java c_syJ<
* I9kBe}g3
* Created on 2007年1月1日, 下午4:57 KL8WT6!RZ
* WFMQ;
* To change this template, choose Tools | Options and locate the template under Sigu p#.p
* the Source Creation and Management node. Right-click the template and choose ~D!Y]
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* Open. You can then make changes to the template in the Source Editor. A9M/n^61
*/ {fu[&@XV
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package com.tot.count; anFl:=
import tot.db.DBUtils; wI2fCq(a0
import java.sql.*; 8YkCTJfBGu
/** )-S;j)(+
* -|_io,eL;
* @author u&$1XZ!es
*/ FSS~E [(DL
public class CountControl{ cb9@
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private static long lastExecuteTime=0;//上次更新时间 P%Wl`NA P
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 hV"2L4/E
/** Creates a new instance of CountThread */ =N{-lyr)
public CountControl() {} f9J]-#I if
public synchronized void executeUpdate(){ k1M?6TW&
Connection conn=null; @wW)#!Mou
PreparedStatement ps=null; S-G#+Ue2
try{ 2Jn?'76`
conn = DBUtils.getConnection(); K]dX5vJw'
conn.setAutoCommit(false); 8!Q0:4Vb
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); StM)lVeF
for(int i=0;i<CountCache.list.size();i++){ ?XO}6q<tM
CountBean cb=(CountBean)CountCache.list.getFirst(); Kw,ln<)2
CountCache.list.removeFirst(); *wK7qS~VB2
ps.setInt(1, cb.getCountId()); "aeKrMgc6V
ps.executeUpdate();⑴ 0vdnM8N2
//ps.addBatch();⑵ N;XJMk_ H
} _@ @"'
//int [] counts = ps.executeBatch();⑶
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conn.commit(); 4L[-[{2
}catch(Exception e){ 7\JA8mm
e.printStackTrace(); R,[+9U|4V
} finally{ e+P|PW
try{ -Khb
if(ps!=null) { DwH=ln=
ps.clearParameters(); =/F\_/Xw
ps.close(); >`+-Yi$(\
ps=null; h_ J|uu
} h*?/[XY
}catch(SQLException e){} cLCzLNyKl
DBUtils.closeConnection(conn); 1F }mlyS
} ~CL^%\K
} 2[$` ]{U
public long getLast(){ <D{_q.`vA
return lastExecuteTime; cy4V*zwp
} 6d|%8.q1
public void run(){ ];G$~[
long now = System.currentTimeMillis(); YfOO]{x,X
if ((now - lastExecuteTime) > executeSep) { RBM4_L
//System.out.print("lastExecuteTime:"+lastExecuteTime); IDr$Vu4LCW
//System.out.print(" now:"+now+"\n"); 3ZU<u;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); \ .jT"Z~
lastExecuteTime=now; Og3bV_,"
executeUpdate(); h`$2/%?
} BFyVq
else{ @ 6{U*vs
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); S)d_A
} 9b*1-1"
} haMt2S2_B:
} Uw5`zl
//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 eA(c{
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类写好了,下面是在JSP中如下调用。 d ;W(Vm6
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<% +A,t9 3:k
CountBean cb=new CountBean(); 9K
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :X;AmLf`2u
CountCache.add(cb); ^ 04|tda
out.print(CountCache.list.size()+"<br>"); ,ZLg=
CountControl c=new CountControl(); -N[Q*;h|
c.run(); u2 xb ^vu
out.print(CountCache.list.size()+"<br>"); +#! !
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