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: u5Up&QE!>q
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CountBean.java /=)L_
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/* a460 |w6
* CountData.java c8Z A5|
* Qz,|mo+
* Created on 2007年1月1日, 下午4:44 rrqQCn9
* gEwd &J
* To change this template, choose Tools | Options and locate the template under Gb2L }
* the Source Creation and Management node. Right-click the template and choose 4^*,jS-9g}
* Open. You can then make changes to the template in the Source Editor. *k [J6
*/ &|9.}Z8U
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package com.tot.count; T95t"g?p
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/** %S@L|t
* M`7y>Ud
* @author eC! #CK
*/ -*B`]
public class CountBean { m$wlflt
private String countType; ]~0}=,H$N
int countId; mwC=o5O
/** Creates a new instance of CountData */ bsS:"/?>
public CountBean() {} ]<XR]FHx)
public void setCountType(String countTypes){ n~.*1. P
this.countType=countTypes; &GhPvrxI?
} CnISe^h
public void setCountId(int countIds){ uw AwWgl
this.countId=countIds; G[,Q95`w?<
} wN=;i#
public String getCountType(){ S($Su7g%_
return countType; 3jZ6kfj
} Y32 "N[yw
public int getCountId(){ M.q=p[
return countId; YXW%]Uy+
} (MLwQiop
} Y?d9l
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CountCache.java x/
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/* ;# uZhd
* CountCache.java 5!X1G8h)uy
* ?6^|ZtB
* Created on 2007年1月1日, 下午5:01 T,%j\0
* W-efv
* To change this template, choose Tools | Options and locate the template under n.}E5%qK
* the Source Creation and Management node. Right-click the template and choose Cbm\h/PXl
* Open. You can then make changes to the template in the Source Editor. p-GAe,2q
*/ T;5r{{
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package com.tot.count; ntVS:F
import java.util.*; vBcq_sbo
/** 2`GOJ,$
* eE
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* @author tDg}Ys=4K>
*/ )2IH
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public class CountCache { [ic 870_
public static LinkedList list=new LinkedList(); *Hz^K0:8(
/** Creates a new instance of CountCache */ f+_h !j
public CountCache() {} v\tEVhm
public static void add(CountBean cb){ PwB1]p=
if(cb!=null){ sEJC-$
list.add(cb); G<|8?6bq#
} Om;&_!i
} !%)F J:p
} |yEa5rd?W
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CountControl.java RTh`ENCKR
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/* Vw|| !d
* CountThread.java $5D,sEC@
* -i yyn^|
* Created on 2007年1月1日, 下午4:57 ngohtB^]
* f y:,_#
* To change this template, choose Tools | Options and locate the template under myl+J;,]
* the Source Creation and Management node. Right-click the template and choose )G^
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* Open. You can then make changes to the template in the Source Editor. ="wzq+ U
*/ y*pUlts<
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package com.tot.count; aI^/X{d
import tot.db.DBUtils; }G4ztiuG
import java.sql.*; 9RN-suE[
/** T&4qw(\G
* Ez|oN,
* @author SCvVt
*/ N ,8/Y
public class CountControl{ /+Lfrt
private static long lastExecuteTime=0;//上次更新时间 AV9m_hZt
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |KSy`lY-j>
/** Creates a new instance of CountThread */ 7Mb#O_eh
public CountControl() {} ojyIQk+
public synchronized void executeUpdate(){ +_XzmjnDd
Connection conn=null; .Asv%p[W
PreparedStatement ps=null; Lzu.)C@Amx
try{ [W%$qZlP
conn = DBUtils.getConnection(); )E@A0 W
conn.setAutoCommit(false); #]nx!*JNZ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 0U%f)mG
for(int i=0;i<CountCache.list.size();i++){ QUU;g 2k
CountBean cb=(CountBean)CountCache.list.getFirst(); vVE2m=!v
CountCache.list.removeFirst(); 1N7Kv4,
ps.setInt(1, cb.getCountId()); 5?hw !
ps.executeUpdate();⑴ %?e& WLS
//ps.addBatch();⑵ mEw ~yOW]M
} X.hm s?]
//int [] counts = ps.executeBatch();⑶ vnWWneeNr
conn.commit(); }:X*7 n(&
}catch(Exception e){ S S2FTb-m
e.printStackTrace(); L#E]
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} finally{ yW$0\E6<r
try{ N"nd*?
if(ps!=null) { oD<kMK
ps.clearParameters(); JSW^dw&
ps.close(); yE}}c{hSn
ps=null; ~//fN}~R
} X!e[GJ
}catch(SQLException e){} $5Xh,DOg
DBUtils.closeConnection(conn); 6d_'4B
} yzqVz_Fi*W
} H&:jcgV*P
public long getLast(){ U2bjFLd"
return lastExecuteTime; 5$V_Hj
} T6 '`l?H`;
public void run(){ bbrXgQ`s+w
long now = System.currentTimeMillis(); c-B
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if ((now - lastExecuteTime) > executeSep) { ^$b Y,CE
//System.out.print("lastExecuteTime:"+lastExecuteTime); WZ.@UN,
//System.out.print(" now:"+now+"\n"); o4|M0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !o:f$6EA~C
lastExecuteTime=now; ]H`1F1=
executeUpdate(); RhncBKm*M
} Ney/[3 A
else{ 8C*c{(4
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); SHe49!RA'{
} z^'gx@YD*v
} S:h{2{
} xai*CY@cQ
//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 .Y&)4+ckL
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类写好了,下面是在JSP中如下调用。 ;M)QwF1
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<% N@t|7~
CountBean cb=new CountBean(); wK?vPS
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Tj:B!>>
CountCache.add(cb); |S_eDjF
out.print(CountCache.list.size()+"<br>"); -[cTx[Z,
CountControl c=new CountControl(); ~ _/(t'9
c.run(); Qk:Y2mL
out.print(CountCache.list.size()+"<br>"); 7pe\M/kl
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