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: 2HVqJib4Yn
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CountBean.java 2 {WZ?H93a
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/* d~_5Jx
* CountData.java zqU$V~5;rG
* 0LC]%x+"
* Created on 2007年1月1日, 下午4:44 h&i(Kfv*
* mpD.x5jm<
* To change this template, choose Tools | Options and locate the template under VJ'-"8tY&
* the Source Creation and Management node. Right-click the template and choose X ]&`"Z]
* Open. You can then make changes to the template in the Source Editor. % +
*/ 7>@0nHec
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package com.tot.count;
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/** f#AuZ]h
*
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* @author LjGLi>kI~
*/ fh_:ung
public class CountBean { w=-{njMz6&
private String countType; 1$# r)S[*
int countId; i)cG
/** Creates a new instance of CountData */ v@2?X4n
public CountBean() {} :-+][ [
public void setCountType(String countTypes){ ?5Z-w
this.countType=countTypes; 8KP
} \QSD*
public void setCountId(int countIds){ K; hP0J
this.countId=countIds; aB G*
} .ozBa778u
public String getCountType(){ { ~{D(k
return countType; ZA_~o#0%
} FB+nN5D/
public int getCountId(){ {hO|{vz
return countId; Cu$`-b^y
} N/0Q`cQ-
} "lA$;\&
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CountCache.java )('{q}JxV
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/* hI<$lEB
* CountCache.java ;SA+|,
* H lFVc
* Created on 2007年1月1日, 下午5:01 *"/BD=INv}
* LWM& k#i
* To change this template, choose Tools | Options and locate the template under S +73 /Vs
* the Source Creation and Management node. Right-click the template and choose )d
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* Open. You can then make changes to the template in the Source Editor. \FO
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*/ |~D~#Nz
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package com.tot.count; ZZ0b!{qj3
import java.util.*; W89J]#v)k
/** ac4dIW{$3
* \=W t{
* @author Q6X}R,KA1
*/ jI}{0LW&F&
public class CountCache { h7]>b'H
public static LinkedList list=new LinkedList(); l`K5fk
/** Creates a new instance of CountCache */ %%O_:@9x,
public CountCache() {} ]=0D~3o3
public static void add(CountBean cb){ <l9qhqHv&
if(cb!=null){ =U~\iJ
list.add(cb);
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} 6ozBU^n
} ORV'dr
} +qF,XJ2
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CountControl.java ##NowO
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/* CH h6Mnw
* CountThread.java Y2p~chx9
* Cd'SPaR
* Created on 2007年1月1日, 下午4:57 ;%i.@@:IQ
* +Mh 9Jf
* To change this template, choose Tools | Options and locate the template under u"r1RG'
* the Source Creation and Management node. Right-click the template and choose P\|i<Ds_M
* Open. You can then make changes to the template in the Source Editor. flfE~_
*/ w~9=6|_
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package com.tot.count; le`_
import tot.db.DBUtils; Ne,u\q3f
import java.sql.*; <wt9K2,
/** 9ev"BO
* Os7 3u#!'
* @author s%qK<U4@;Q
*/ ma M8:\
public class CountControl{ s*pgR=dZZ
private static long lastExecuteTime=0;//上次更新时间 ep"54o5=d
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 U5wO;MA
/** Creates a new instance of CountThread */ ]hkway
public CountControl() {} [I` 6F6
public synchronized void executeUpdate(){ ;yH1vX
Connection conn=null; gobqS+c
PreparedStatement ps=null; 7e-l`]
try{ H0B"?81
conn = DBUtils.getConnection(); Z-+p+34ytq
conn.setAutoCommit(false); ^^Tu/YC9x
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); V qW(S1w
for(int i=0;i<CountCache.list.size();i++){ GzUgzj|BN~
CountBean cb=(CountBean)CountCache.list.getFirst(); ojH-;|f
CountCache.list.removeFirst(); ~FV
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ps.setInt(1, cb.getCountId()); i;>Hy|
ps.executeUpdate();⑴ \YBY"J
//ps.addBatch();⑵ _,4f z(
} f[/E $r99J
//int [] counts = ps.executeBatch();⑶ #_bSWV4
conn.commit(); `cr.C|RT:
}catch(Exception e){ S)*eAON9
e.printStackTrace(); Qy @r&
} finally{ o5FBqt
try{ )rs);Pl
if(ps!=null) { ~T[m{8uh
ps.clearParameters(); AcYL3
ps.close(); v(t?d
ps=null; MW+]w~7_Q
} Q
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}catch(SQLException e){} $fY4amX6Z
DBUtils.closeConnection(conn); i.Qy0
} ` 0k
} LPk85E
public long getLast(){ \TrhJ
return lastExecuteTime; ~WJEH#
} B/Lx,
public void run(){ _6
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long now = System.currentTimeMillis(); (k..ll p~
if ((now - lastExecuteTime) > executeSep) { J,E'F!{
//System.out.print("lastExecuteTime:"+lastExecuteTime); h^5'i}@u
//System.out.print(" now:"+now+"\n"); Ui46p
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "rr,P0lgX
lastExecuteTime=now; *Gm%Dn
executeUpdate(); {=><@]N
} NTVdSK7z~H
else{ *r+i=i8{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); zKWcDbj
} fD<3Tl8U0
} }IGr%C(3%
} kN>AY'1
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 x=bAR%i~
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类写好了,下面是在JSP中如下调用。 >w?O?&Q$
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<% w7"Z@$fs
CountBean cb=new CountBean(); KwRO?G9&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )A['+s
CountCache.add(cb); ![iAALPNl
out.print(CountCache.list.size()+"<br>"); 4y+]V~p
CountControl c=new CountControl(); 7@m
c.run();
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out.print(CountCache.list.size()+"<br>"); !G#3jh:kiY
%>