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: ~!:F'}bj
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CountBean.java #e9B|Y?b
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/* (j-(fS
* CountData.java >Mvt;'c
* t S!~>X
* Created on 2007年1月1日, 下午4:44 gcv,]v8
* 1/&j'B
* To change this template, choose Tools | Options and locate the template under P%/+?(?
* the Source Creation and Management node. Right-click the template and choose *E$D,
* Open. You can then make changes to the template in the Source Editor. zZf#E@=$|
*/ !o.g2
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package com.tot.count; z4f5@
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/** t: [[5];E
* XD|&{/O
* @author Q]|+Y0y}X
*/ .qVdo+M%F
public class CountBean { 2<988F
private String countType; *50Ykf
int countId; Aga7X@fV(
/** Creates a new instance of CountData */ R#T6Ii
public CountBean() {} Ab(bvS8r$
public void setCountType(String countTypes){ 0c3G_I=
this.countType=countTypes; tXp)o>"
} KX9ZwsC0
public void setCountId(int countIds){ /4T%s
this.countId=countIds; ?v")Z0 ~
} IvO3*{k,
public String getCountType(){ ,]cd%w9
return countType; D:F!;n9
} *=sU+x&X
public int getCountId(){ 1i>)@{P&BN
return countId; CI @I
} x`lBG%Y[-v
} {K|{a
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CountCache.java z?gJHN<
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/* ]3I_H+hU
* CountCache.java N9*$'
* tP:xx2N_
* Created on 2007年1月1日, 下午5:01 RV($G8U
* k[zf`x^
* To change this template, choose Tools | Options and locate the template under ?.Kl/8ml
* the Source Creation and Management node. Right-click the template and choose 'PO1{&M
* Open. You can then make changes to the template in the Source Editor. 4o=G) KO{
*/ X'u`\<&W
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package com.tot.count; 'rF TtT
import java.util.*; 6XG+YIG6w
/** -[7.VP
* nut7b
* @author Kp&d9e{
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*/ +Rh'VZJs
public class CountCache { X<?;-HrS;
public static LinkedList list=new LinkedList(); 5$#<z1M.&
/** Creates a new instance of CountCache */ ZHF@k'vm/9
public CountCache() {} DMf9wB
public static void add(CountBean cb){ P;y/`_jo
if(cb!=null){ xp&I~YPH
list.add(cb); l%U9g
} tou^p-)GQ|
} y7w>/7q
} ^{Vm,nAQqs
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CountControl.java o j^U
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/* [cH/Y2[
* CountThread.java {otvJ|'N
* ~Ep&:c4:D
* Created on 2007年1月1日, 下午4:57 I&vB\A
* ~kHir]jc
* To change this template, choose Tools | Options and locate the template under /;lk.-yU
* the Source Creation and Management node. Right-click the template and choose l9jcoVo.
* Open. You can then make changes to the template in the Source Editor. tT
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*/ 3dM6zOK
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package com.tot.count; 81n%2G
import tot.db.DBUtils; c49#aNR
import java.sql.*; AH}
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/**
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* rvG qUmSUs
* @author cK258mY
*/ ]6aM %r=c
public class CountControl{ t #AQD]h
private static long lastExecuteTime=0;//上次更新时间 Iq5F^rH`[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 q3[LnmH
/** Creates a new instance of CountThread */ UkYQ<MNO
public CountControl() {} i3~!ofTb
public synchronized void executeUpdate(){ F+6ZD5/
Connection conn=null; p!691LI
PreparedStatement ps=null; O3_Mrn(R
try{ u)V*o
conn = DBUtils.getConnection(); PQ[TTLG\&
conn.setAutoCommit(false); *[U:'o`67
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); q+DH2&E'
for(int i=0;i<CountCache.list.size();i++){ fg9sZ%67]\
CountBean cb=(CountBean)CountCache.list.getFirst(); z_H2L"Z
CountCache.list.removeFirst(); 2Fh_
ps.setInt(1, cb.getCountId()); &p%,+|
ps.executeUpdate();⑴ jmb\eOq+~V
//ps.addBatch();⑵ Kzm_AHA)
} 2ReulL8j
//int [] counts = ps.executeBatch();⑶ d}G?iX;c}
conn.commit(); U!'lc}5
}catch(Exception e){ %MIu;u FR
e.printStackTrace(); /}VQzF
} finally{ she`_'?5
try{ jTqba:q@
if(ps!=null) { 3xe8DD
ps.clearParameters(); P]TT
ps.close(); wiVQMgi`
ps=null; 8fN0"pymo
} zPmVECS
}catch(SQLException e){} _c&*'IY[V
DBUtils.closeConnection(conn); ^Y&Cm.w
} ^d"J2n,7L
} oaKf{$vg
public long getLast(){ V":BAn
return lastExecuteTime;
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} 70NHU;&N
public void run(){ k`t'P6
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long now = System.currentTimeMillis(); Ao\Vh\rQkq
if ((now - lastExecuteTime) > executeSep) { 8x{vgx @M
//System.out.print("lastExecuteTime:"+lastExecuteTime); vBpg6
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//System.out.print(" now:"+now+"\n"); 1D`RR/g&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7mjj%
lastExecuteTime=now; QA3l:D}u
executeUpdate(); KZE.}8^%D
} ZChY:I$<
else{ e!8_3BE
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); R*y[/Aw
} .~8+s.y
} W(8g3
} {aL$vgYT1
//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 :}-u`K*
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类写好了,下面是在JSP中如下调用。 EzyIsp> _
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<% yjO7/<2
CountBean cb=new CountBean(); 9JtvHUkO
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); N|j.@K
CountCache.add(cb); RmQt%a7\{
out.print(CountCache.list.size()+"<br>"); %8tN$8P
CountControl c=new CountControl(); )L!R~F
C
c.run();
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out.print(CountCache.list.size()+"<br>"); +E:(-$"R
%>