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: od1omYsR
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CountBean.java W_\L_)^X
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/* lzG;F]
* CountData.java K<6x4ha
* k!=GNRRZE
* Created on 2007年1月1日, 下午4:44 g@i>R>
* VtiqAh}4
* To change this template, choose Tools | Options and locate the template under ;J-Ogt @d7
* the Source Creation and Management node. Right-click the template and choose vQmackY
* Open. You can then make changes to the template in the Source Editor. <C%-IZv$
*/ 8$ZSF92C
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package com.tot.count; Q5nyD/k4c
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/** 9jGuelwN
* Sn2Ds)Pfx3
* @author |$w={N^4
*/ xg,]M/J
public class CountBean { MW$H/:3
private String countType; ASZ5;N4u
int countId; H
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/** Creates a new instance of CountData */ QYfAf3te
public CountBean() {} Mp"ci+Iu
public void setCountType(String countTypes){ *rcuhw"^b#
this.countType=countTypes; LQ\
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} P^3m:bE]
public void setCountId(int countIds){ mERrcY Y{
this.countId=countIds; ;%7XU~<a
} O
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public String getCountType(){ cbCE
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return countType; 6!%d-Z7)
} Kwl qi]~
public int getCountId(){ +GYMJK`S+
return countId; ?3,64[
} Uk*;C
} )yNw2+ ~5
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CountCache.java 37O#aJ,K
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/* `+hy#1]
* CountCache.java ))IgB).3M
* ra%R:xX
* Created on 2007年1月1日, 下午5:01 <a+eF}*2
* Naf`hE9
* To change this template, choose Tools | Options and locate the template under MeI2i
* the Source Creation and Management node. Right-click the template and choose I,<>%Z|'
* Open. You can then make changes to the template in the Source Editor. !/4V^H
*/ qBBYckS.
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package com.tot.count; we\b]
import java.util.*; )-.Cne;n
/** 3j+=3n,
* LZQFj/,Jg
* @author ) _9e@~,
*/ A&|Wvb=
public class CountCache { D]pK=247
public static LinkedList list=new LinkedList(); hINnb7o
/** Creates a new instance of CountCache */ rKzv8d
public CountCache() {} S< EB&P
public static void add(CountBean cb){ E+m]aYu"
if(cb!=null){ u+z .J4w
list.add(cb); KkdG.c'
} 84p[N8
} + q
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} O^X[9vrW
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CountControl.java xm}q6>jRV
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/* wRXn9
* CountThread.java X(r)Z\
* ]]J#7L#
* Created on 2007年1月1日, 下午4:57 {t844La"
* W(uP`M%][0
* To change this template, choose Tools | Options and locate the template under y:g7'+c
* the Source Creation and Management node. Right-click the template and choose T6h;Y
* Open. You can then make changes to the template in the Source Editor. C.yY8?|
*/ bK03S Vx
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package com.tot.count; c&7Do}
import tot.db.DBUtils; wJ80};!
import java.sql.*; ?%\mQmjas
/** ^%n124
* &YT_#M
* @author N?qIpv/a.
*/ Sni&?tcY
public class CountControl{ 2
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private static long lastExecuteTime=0;//上次更新时间 [;(]Jy
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 GB&Nt{
/** Creates a new instance of CountThread */ P]pmt1a
public CountControl() {} <@u0.-]
public synchronized void executeUpdate(){ KI Ek/]<H
Connection conn=null; -W|*fKN`3
PreparedStatement ps=null; 8ivRp<9
try{ R&6n?g6@/V
conn = DBUtils.getConnection(); )8pcf`h{
conn.setAutoCommit(false); >Hdjsu5{N
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [ 3$.*
for(int i=0;i<CountCache.list.size();i++){ .cw!ls7d
CountBean cb=(CountBean)CountCache.list.getFirst(); w) =eMdj\o
CountCache.list.removeFirst(); n_<mPU
ps.setInt(1, cb.getCountId()); 7d3'CQQ4
ps.executeUpdate();⑴ HzP.aw4
//ps.addBatch();⑵ [X;>*-
} >j&1?M2C
//int [] counts = ps.executeBatch();⑶ pG0!ALT
conn.commit(); ^g9}f
}catch(Exception e){ WI,40&<
e.printStackTrace(); J1.qhy>
} finally{ j h;
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try{ `Jn,IDq
if(ps!=null) { OZG0AX+=#
ps.clearParameters(); KuA>"X
ps.close(); ?K0U3V$s
ps=null; 3"5.eZSOW
} s>T`l
}catch(SQLException e){} Uf# PoQ!y
DBUtils.closeConnection(conn); Y;8
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} a lrt*V|=
} >Cvjs
public long getLast(){ F#6cF=};@
return lastExecuteTime; ?p(kh^ z
} iDZrK%fl
public void run(){ u0xQ;BQ
long now = System.currentTimeMillis(); |,3l`o
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if ((now - lastExecuteTime) > executeSep) { ,NDh@VYe
//System.out.print("lastExecuteTime:"+lastExecuteTime); :JR<SFjm
//System.out.print(" now:"+now+"\n"); S0F@#mSQ?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Z+0?yQ=%
lastExecuteTime=now; 9J?W '8s5
executeUpdate(); n<E.Em1
} Te+^J8
else{ sD2
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); N3ZiGD
} =:4?>2)
} Khj=llo,
} c)03Ms4
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//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 e|VJ9|;3
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类写好了,下面是在JSP中如下调用。 }?J~P%HpF
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<% Oo
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CountBean cb=new CountBean(); 4Hk6b09
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xo(k?+P>.
CountCache.add(cb); $Buf#8)F*
out.print(CountCache.list.size()+"<br>"); 3 q"7K
CountControl c=new CountControl(); X($6IL6m
c.run(); rhIGOk1k
out.print(CountCache.list.size()+"<br>"); LP ,9<&"<
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