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: \ _-kOS
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CountBean.java P^uP$D
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/* Q
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* CountData.java 6cgpg+-a
* wXIe5
* Created on 2007年1月1日, 下午4:44 2s]]!{Z#
* f0HV*%8
* To change this template, choose Tools | Options and locate the template under D!OG307P
* the Source Creation and Management node. Right-click the template and choose +lk\oj$S+
* Open. You can then make changes to the template in the Source Editor. inq4CGY
*/ 4P-'(4I)
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package com.tot.count; Pv/%s) &y&
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/** ,]>`guDV
* leX7(Y;!a7
* @author GakmROZ@9
*/ }.Na{]<gh
public class CountBean { C7c|\ T
private String countType; oto
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int countId; fs)q7 7g
/** Creates a new instance of CountData */ Jte:l:yjtA
public CountBean() {} jmZ|b6
public void setCountType(String countTypes){ nfCd*f
this.countType=countTypes; zei9,^
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} O. .@<.
public void setCountId(int countIds){
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this.countId=countIds; Cs~\FI1wR
} =^%Pwkz
public String getCountType(){ hj m.Ath
return countType; (Db*.kd8,
} .k!k-QO5La
public int getCountId(){ (<:rKp
return countId; l5N\>q
} A=YEY n
} A$9_aqbj
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CountCache.java _UVX
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/* C\hZ;Z1
* CountCache.java k0Vo
* vSHIl"h
* Created on 2007年1月1日, 下午5:01 "n2xn%t{
* zdpLAr
* To change this template, choose Tools | Options and locate the template under 0o^#Fmuz
* the Source Creation and Management node. Right-click the template and choose 6jy n,GU
* Open. You can then make changes to the template in the Source Editor. g`f6gxc
*/ /w0v5X7
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package com.tot.count; =QxE-)v
import java.util.*; +h\W~muR
/** +ouy]b0`t
* ~"4 vd 3
* @author '%|20j
*/ \"sSS.'
public class CountCache { 5yN8%_)T
public static LinkedList list=new LinkedList(); eABdye
/** Creates a new instance of CountCache */ 6O|\4c;
public CountCache() {} D*2p
public static void add(CountBean cb){ $d"f/bRWy
if(cb!=null){ 1069]
list.add(cb); qKb-aP-
} !kk %;XSZ
} uZ39Vx
} Y_ ;i
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CountControl.java 576-X_a,
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/* #+DmH
* CountThread.java R.WsC bU
* V/wc[p
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* Created on 2007年1月1日, 下午4:57 r7BH{>-
* {p_vR/yN
* To change this template, choose Tools | Options and locate the template under #o |&MV_j
* the Source Creation and Management node. Right-click the template and choose #*aGzF
* Open. You can then make changes to the template in the Source Editor. tH|Q4C
*/ A ** M"T
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package com.tot.count; FSZoT!
import tot.db.DBUtils; Rb>RjHo S
import java.sql.*; Hn]n]wsLy
/** &DhA$o "'
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* @author QRG)~
*/ :8!3*C-=
public class CountControl{ E1 gTrMo
private static long lastExecuteTime=0;//上次更新时间 {3p7`h~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 qYiK bzy
/** Creates a new instance of CountThread */ PC(iqL8r
public CountControl() {} Pge }xKT
public synchronized void executeUpdate(){ 2P>za\
Connection conn=null; rOf
PreparedStatement ps=null; $Aoqtz d\
try{ F p=Q$J|
conn = DBUtils.getConnection(); YKxA2`3v%
conn.setAutoCommit(false); X\)KVn`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Y>!W&Gtu
for(int i=0;i<CountCache.list.size();i++){ *SG2k .$
CountBean cb=(CountBean)CountCache.list.getFirst(); d"`>&8*
CountCache.list.removeFirst(); +6Fdi*:
ps.setInt(1, cb.getCountId()); 'oeg[
ps.executeUpdate();⑴ {gHscj;SM
//ps.addBatch();⑵ eeTaF!W
} SIVLYi
//int [] counts = ps.executeBatch();⑶ X^ ]$/rI)
conn.commit(); yl+)I
}catch(Exception e){ K[yJu 4
e.printStackTrace(); _eeX]xSSl
} finally{ 34M.xB
try{ csA.3|rv
if(ps!=null) { bh6wI%8H
ps.clearParameters(); w^6N
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ps.close(); 3EX&.OL!
ps=null; v?=VZ~`O(
} |}.B!vg(4
}catch(SQLException e){} *H<g9<Dn
DBUtils.closeConnection(conn); QgM_SY|Rj
} ~g6[ [
} )$N{(Cke2T
public long getLast(){ =WRU<`\
return lastExecuteTime; R6o<p<fTh
} { RX|
public void run(){ jY6=+9Jz5
long now = System.currentTimeMillis(); ;m:GUp^[
if ((now - lastExecuteTime) > executeSep) { 8VGXw;(Y,d
//System.out.print("lastExecuteTime:"+lastExecuteTime); (mr`?LI}
//System.out.print(" now:"+now+"\n"); @[Qg}'i
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); l0 :xQV`
lastExecuteTime=now; k3h53QTmC
executeUpdate(); &{{f|o=u.
} eZkz 1j~
else{ BQ)43Rr>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); w/Dm
} zk~ rKQ,
} 2l4 i-;
} 6Tmb@<I_
//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 ^`5Yxpz
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类写好了,下面是在JSP中如下调用。 m:<3d]L
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<% !+ hgKZ]
CountBean cb=new CountBean(); Y[]t_o)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {NqGWkGt*b
CountCache.add(cb); w:@M|O4`
out.print(CountCache.list.size()+"<br>"); <:t\P.
CountControl c=new CountControl(); hRcJ):Wyb
c.run(); A'R sy6
out.print(CountCache.list.size()+"<br>"); }H^^v[4
%>