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: r' 97\|
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CountBean.java 3l41r[\
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/* 1bFEx_
* CountData.java Hf`&&
* l.Lc]ZpB
* Created on 2007年1月1日, 下午4:44 {#d`&]
* Jf8'N
ot
* To change this template, choose Tools | Options and locate the template under &El[
* the Source Creation and Management node. Right-click the template and choose g
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* Open. You can then make changes to the template in the Source Editor. g]TI8&tP!L
*/ fitK2d
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package com.tot.count; +L<w."WG
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/** ).@)t:uNa
* |<5J
* @author )gm \e?^
*/ r.W"@vc>
public class CountBean { Jg?pW:}R
private String countType; x Ps&CyI
int countId; Sd/d [
/** Creates a new instance of CountData */ LqH?3):
public CountBean() {} ,YzC)(-
public void setCountType(String countTypes){ :5qqu{GL
this.countType=countTypes;
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} aO;Q%]VL'
public void setCountId(int countIds){ lj% ;d'
this.countId=countIds; [s&
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} CH|g
public String getCountType(){ N'q/7jOy
return countType; fjzr8vU}C
} zv3<i (
public int getCountId(){ 4<!}4
return countId; Yru1@/;
} #0$eTdx#
} P St|!GST
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CountCache.java 8Gzs
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/* /E1c#@
* CountCache.java I$sm5oL
* EXScqGa]
* Created on 2007年1月1日, 下午5:01 G5Dji_ |
* ,4?|}xg
* To change this template, choose Tools | Options and locate the template under hJL0M!
* the Source Creation and Management node. Right-click the template and choose u8)r
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* Open. You can then make changes to the template in the Source Editor. ;z=C^'
*/ ^SelqX
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package com.tot.count; Y)-)NLLG;n
import java.util.*; " kJWWR
/** -O,O<tOm
* P#'DG W&W0
* @author \6PIw-)
*/ ^[,1+WS%
public class CountCache { E`LIENm
public static LinkedList list=new LinkedList(); 1=cfk#
/** Creates a new instance of CountCache */ & ;x1Rx
public CountCache() {} &|,qsDK(
public static void add(CountBean cb){ wBaFC\CW
if(cb!=null){ 4~J1pcBno%
list.add(cb); 4pHPf<6
} k?*DBXJv
} g960;waz3
} ri_6wbPp
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CountControl.java ~+NFWNgN
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/* .J!
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* CountThread.java %EhU!K#[
* )#TJw@dNf^
* Created on 2007年1月1日, 下午4:57 ROiX=i
* 0}3'h#33=
* To change this template, choose Tools | Options and locate the template under hdWp
* the Source Creation and Management node. Right-click the template and choose '%/u103{e
* Open. You can then make changes to the template in the Source Editor. */m~m?
*/ 2nz'/G
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package com.tot.count; Ih0>]h-7
import tot.db.DBUtils; Z`Eb
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import java.sql.*; eEb1R}@
/** F1]PYx$X
* YSUH*i/%
* @author pzp"NKxi
*/ Zvw3C%In
public class CountControl{ 9MlfZsby
private static long lastExecuteTime=0;//上次更新时间 \7?MUa.4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AZ@Zo'
/** Creates a new instance of CountThread */ Bwvc@(3v
public CountControl() {} q|_ 5@Ly
public synchronized void executeUpdate(){ !ES#::;z?
Connection conn=null; LR?#H)$
PreparedStatement ps=null; wEn&zZjx
try{ ktJLpZ<0O
conn = DBUtils.getConnection(); 79fyn!Iz<
conn.setAutoCommit(false); SYhspB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %3B>1h9N
for(int i=0;i<CountCache.list.size();i++){ .0/Z'.c8
CountBean cb=(CountBean)CountCache.list.getFirst(); m l
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CountCache.list.removeFirst(); PX{~! j%n
ps.setInt(1, cb.getCountId()); oN}j <6s
ps.executeUpdate();⑴ Q`fA)6U
//ps.addBatch();⑵ Bc,z]
} !6`nN1A
//int [] counts = ps.executeBatch();⑶ w)c#ZJHG
conn.commit(); #NxvLW/
}catch(Exception e){ u,k8i:JY
e.printStackTrace(); ju6_L<
} finally{ m9i%U
try{ cB'4{R@e
if(ps!=null) { F476"WF
ps.clearParameters(); ^mb*w)-p?
ps.close(); JO$]t|I
ps=null; |?Uc:VFF
} B_G7F[/K
}catch(SQLException e){} ZuV
DBUtils.closeConnection(conn); \)
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} ?UZyu4O%
} GM92yi!8
public long getLast(){ #SUq.A
return lastExecuteTime; `I:,[3_/
} +0042Yi
public void run(){ LOo#
long now = System.currentTimeMillis(); WY UU-
if ((now - lastExecuteTime) > executeSep) { s8O+&^(U
//System.out.print("lastExecuteTime:"+lastExecuteTime); WkmS
//System.out.print(" now:"+now+"\n"); :Fk&2WsW:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); yUlQPrNX
lastExecuteTime=now; r>eXw5Pr7
executeUpdate(); f}uCiV!?v
} Bnc
else{ tHo/uW_~I
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); c8W=Is`
} ;]ew>P)
} !ry+ r!"
} $e\R5Lu
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 0]W/88ut*u
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类写好了,下面是在JSP中如下调用。 hkc_>F]Hx
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<% ?*dx=UI
CountBean cb=new CountBean(); ps
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =ZL20<TeH
CountCache.add(cb); XV!EjD~q
out.print(CountCache.list.size()+"<br>"); j<5R$^?U
CountControl c=new CountControl(); $dUN+9
c.run(); 8=Ht+Br
out.print(CountCache.list.size()+"<br>"); \OB3gnR
%>