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: 22P$ ~ch
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CountBean.java *1Z5+uVT[
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/* FSuAjBl0-
* CountData.java i JxQB\x
* $QEilf;E
* Created on 2007年1月1日, 下午4:44 /%aiEhL
* Syp"L;H8Em
* To change this template, choose Tools | Options and locate the template under 7r+g8+4
* the Source Creation and Management node. Right-click the template and choose ZI;<7tF_z
* Open. You can then make changes to the template in the Source Editor. hd V1nS$
*/ tGdf/aTjy
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package com.tot.count; oY~ Dg
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/** Z4$cyL'$P
* [
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* @author Rv,JU6>i
*/ I
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public class CountBean { )Rat0$6
private String countType; 8n BL\{'B[
int countId; Ioy
/** Creates a new instance of CountData */ 8mLP5s!7
public CountBean() {} L\{IljA
public void setCountType(String countTypes){ ;|p$\26S)%
this.countType=countTypes; S_T^G` [
} dm"n%
public void setCountId(int countIds){ [ao
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this.countId=countIds; O|A_PyW
} ; R=.iOn
public String getCountType(){ BG^C9*ZuP
return countType; R.[Z]-X
} $P7iRM]
public int getCountId(){ j6~nE'sQ
return countId; X7UuwIIP
} ;g_>
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} G!8Z~CPF
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CountCache.java ]{
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/* bb42v7?
* CountCache.java b?4/#&z]
* n26Y]7N
* Created on 2007年1月1日, 下午5:01 Kz<@x`0
* 8By,#T".
* To change this template, choose Tools | Options and locate the template under &Lt[WT$
* the Source Creation and Management node. Right-click the template and choose ultG36.x
* Open. You can then make changes to the template in the Source Editor. \7MHaQvS
*/ ]W0EVf=,k
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package com.tot.count; S|rgCh!h
import java.util.*; Dlo xrdOY&
/** 6ZgU"!|r
* cr?7O;,
* @author to8X=80-3
*/ JxLf?ad.
public class CountCache { }7G8|54t
public static LinkedList list=new LinkedList(); FG3UZVUg9
/** Creates a new instance of CountCache */ dw~p?[
public CountCache() {} "x941}
public static void add(CountBean cb){ L{l6Dd43q
if(cb!=null){ ~A<H9Bw
list.add(cb); )2UZ% ?V#
} 2Nxm@B` {
} :{'k@J"|a
} U7xmC
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CountControl.java {
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/* 'sp-%YlM -
* CountThread.java q'oMAM f}
* M L7\BT
* Created on 2007年1月1日, 下午4:57 Ov-b:lH
* Gc.P,K/hr
* To change this template, choose Tools | Options and locate the template under 2nb:)
* the Source Creation and Management node. Right-click the template and choose 2RF^s.W
* Open. You can then make changes to the template in the Source Editor. $rXh0g
*/ B,z<%DAE
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package com.tot.count; s%iOUL2/
import tot.db.DBUtils; }
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import java.sql.*; Kx"<J@
/** SxyONp.$\
* w|mb4AyL{?
* @author KtS)'jf
*/ d|Gl`BG
public class CountControl{ EA.D}X C
private static long lastExecuteTime=0;//上次更新时间 M,j(=hRJ/E
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zPEg
/** Creates a new instance of CountThread */ juAMAplf
public CountControl() {} 2;L|y._`w
public synchronized void executeUpdate(){ !$A 37j6
Connection conn=null; m`4R]L]
PreparedStatement ps=null; 'B83m#HR#
try{ *xf ._~E
conn = DBUtils.getConnection(); 6b8;}],|
conn.setAutoCommit(false); EzW)'Zzw~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); dk
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for(int i=0;i<CountCache.list.size();i++){ @4%L36k
CountBean cb=(CountBean)CountCache.list.getFirst(); k^$+n_
CountCache.list.removeFirst(); J68j=`Y
ps.setInt(1, cb.getCountId()); I"AYWo?
ps.executeUpdate();⑴ Ub0/r$]DK
//ps.addBatch();⑵ $(s\{(Wn
} _$<Gyz*
//int [] counts = ps.executeBatch();⑶ U%7i=Z{^Ks
conn.commit(); 5`~mmAUk;`
}catch(Exception e){ 8$|8`;I(
e.printStackTrace(); ""O"
} finally{ `<^VR[Mx
try{ K.C>
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if(ps!=null) { 4fh^[\
ps.clearParameters(); 0s#vwK13
ps.close(); }MR1^
ps=null; {)- .xG
} oMcK`%ydm
}catch(SQLException e){} gADmN8G=
DBUtils.closeConnection(conn); .*=]gZ$IE
} NT%W;)6m9
} :J}t&t
public long getLast(){ z
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return lastExecuteTime; <1w/hy&mWN
} C0.'_
public void run(){ eZ a:o1y
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { %zC[KE*~
//System.out.print("lastExecuteTime:"+lastExecuteTime); SgMrce<;
//System.out.print(" now:"+now+"\n"); HQ9f ,<
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); F Kc;W
lastExecuteTime=now; E}CiQUx
executeUpdate(); R cY>k
} )T907I|
else{ l=`L7| ^/d
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); @vgG1w
} uBg 8h{>
} [MX;,%;;
} ^/wfXm
//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 s)voII&
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类写好了,下面是在JSP中如下调用。 c_{z(W"
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<% d lH$yub
CountBean cb=new CountBean(); nM=e]qH
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Y**|N8e
CountCache.add(cb); 4!$
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out.print(CountCache.list.size()+"<br>"); -7WW[
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CountControl c=new CountControl(); 78n=nHS
c.run(); 2^~<("+w
out.print(CountCache.list.size()+"<br>"); (-7ZI"Ku
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