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: /@LUD=
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CountBean.java ,T+.xB;Q@
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/* (:7Z-V2(
* CountData.java 3lefB
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* vUJQ<D
* Created on 2007年1月1日, 下午4:44 [-3x *?Ju
* kY~o3p<
* To change this template, choose Tools | Options and locate the template under 6CNxb
* the Source Creation and Management node. Right-click the template and choose Mqmy*m[U
* Open. You can then make changes to the template in the Source Editor. V_=7q=9mV
*/ p8E6_%Rw
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package com.tot.count; \U HI%1^
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/** tI+P&L"
* U)qG]RI
* @author +J2;6t
*/ T<u QhPMw
public class CountBean { [CG*o>n&|
private String countType; 0G#s/u#
int countId; Y?IX V*J
/** Creates a new instance of CountData */ p}yp!(l
public CountBean() {} ?.69nN
public void setCountType(String countTypes){ c(lG_"q6
this.countType=countTypes; vC-5_pl
} Y:]m~-T
public void setCountId(int countIds){ tS3{y*yi
this.countId=countIds; [R{%r^"2p
} ~JDVoS;>jU
public String getCountType(){ w\5;;9_#
return countType; 9S<atMB
} !<4 =@
public int getCountId(){ SG-Xgr@
return countId; rSNaflYAr
} RhSoD.Da
} s.>;(RiJd
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CountCache.java M}N[> ,2'
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/* bA(-7l?
* CountCache.java @[hD;xO
* ^wb$wtL('
* Created on 2007年1月1日, 下午5:01 w72\'
* G"F:68
* To change this template, choose Tools | Options and locate the template under N/r8joi#
* the Source Creation and Management node. Right-click the template and choose aQL$?,
* Open. You can then make changes to the template in the Source Editor. U
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*/ $5J~4B"%3
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package com.tot.count; [Qn$i/`J
import java.util.*; c7t .
/**
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* @author Tu}?Q.pKo
*/ =g$>]AE
public class CountCache { KDJ-IXoU
public static LinkedList list=new LinkedList(); fH?s~X]
/** Creates a new instance of CountCache */ [?moS!
public CountCache() {} 2D'$
public static void add(CountBean cb){ eBg:[44V
if(cb!=null){ e c4vX
list.add(cb); .v_-V?7
} 0yBiio
} ;hJz'&UWQ
} P] qL&_
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CountControl.java NrWgaPO)i
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/* &4jc3_UKV
* CountThread.java !ZzDSQ;
* 9{XV=a v
* Created on 2007年1月1日, 下午4:57 6"u"B-cz
* ,?`Zrxe[
* To change this template, choose Tools | Options and locate the template under k/2TvEV3=
* the Source Creation and Management node. Right-click the template and choose ngC^@*XAw9
* Open. You can then make changes to the template in the Source Editor. 0E/,l``p
*/ +L|-W9"@3
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package com.tot.count; w ;xbQZ|+
import tot.db.DBUtils; bTW#
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import java.sql.*; G^qt@,n$;
/** 5PPaR|c3
* e&ci\x%
* @author X.J$
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*/ t-VU&.Y
public class CountControl{ whh#J
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private static long lastExecuteTime=0;//上次更新时间 &W$s-qf".
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 b!c2j
/** Creates a new instance of CountThread */ I9O%/^5^[w
public CountControl() {} ]T1\gv1~
public synchronized void executeUpdate(){ ^/DP%^D
Connection conn=null; $Lt'xW`8
PreparedStatement ps=null; %v,a3^Qu
try{ G)3Q|Vc
conn = DBUtils.getConnection(); P|QM0GI
conn.setAutoCommit(false); -5d^n\CDK
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); J @^Ypq
for(int i=0;i<CountCache.list.size();i++){ tu5T^"BqO
CountBean cb=(CountBean)CountCache.list.getFirst(); 6QG"~>v7'(
CountCache.list.removeFirst(); 4-JyK%m,0
ps.setInt(1, cb.getCountId()); S)=3%toS>
ps.executeUpdate();⑴ 0artR~*}
//ps.addBatch();⑵ g&?{^4t]
} L(t!C~3
//int [] counts = ps.executeBatch();⑶ (svKq(X
conn.commit(); .r\|9 *j<
}catch(Exception e){ /xw}]Fa5
e.printStackTrace(); in#lpDa[
} finally{ M992XXd
try{ ZXC_kmBN/
if(ps!=null) { k8E{pc6;
ps.clearParameters(); 4{CeV7
ps.close(); 0Q!/A5z
ps=null; uXo?
} x<\5Jrqt
}catch(SQLException e){} Df.eb|[{
DBUtils.closeConnection(conn); _o'a|=Osx>
} g1&>.V}!
} EClx+tz;`
public long getLast(){ F-%Hw
return lastExecuteTime; -SUK [<=X
} \t?rHB3"
public void run(){ h8hyQd$!
long now = System.currentTimeMillis(); *1g3,NMA
if ((now - lastExecuteTime) > executeSep) { xzz0uk5
//System.out.print("lastExecuteTime:"+lastExecuteTime); tx ,q=.(
//System.out.print(" now:"+now+"\n"); @!p0<&R@x
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); l-?#oy
lastExecuteTime=now; Mew,g:m:
executeUpdate(); %Z+FX,AK
} H_FT%`iM
else{ ;C,t`(
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); JiFB<Q\
} c;.jo?RR2
}
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} a7n`(}?Y
//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 !4+ FN)
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类写好了,下面是在JSP中如下调用。 Hb3t|<z
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<% (CInt_dBw~
CountBean cb=new CountBean(); V)A7q9Bum
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); r -$VPW
CountCache.add(cb); /_1q)`NYy
out.print(CountCache.list.size()+"<br>"); *>E_lWW.
CountControl c=new CountControl(); {h0T_8L/
c.run(); o'K= X E
out.print(CountCache.list.size()+"<br>"); N^4CA@'{
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