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: Ba%b]vp
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CountBean.java }p9#Bzc
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/* zU|'IW&
* CountData.java TuwSJS7
* ZQ\O|
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* Created on 2007年1月1日, 下午4:44 Z2]\k|%<Fa
* ZOJ7^g
* To change this template, choose Tools | Options and locate the template under ,/p.!+
* the Source Creation and Management node. Right-click the template and choose 7bM
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* Open. You can then make changes to the template in the Source Editor. @, z4{B
*/ uF*tlaV6
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package com.tot.count; TDR#'i
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/** lz#@_F|.*
* Hg(nC*#/Q
* @author
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*/ EF6"PH+J@
public class CountBean { mFC9\
private String countType; <;Td8T;
int countId; ,UT :wpc^i
/** Creates a new instance of CountData */ ~05(92bK
public CountBean() {} &xFs0Ri(
public void setCountType(String countTypes){
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this.countType=countTypes; 8;,(D#p
} `C*psS
public void setCountId(int countIds){ ARB^]
this.countId=countIds; 3=lQZi<]%
} cn$0^7?
public String getCountType(){ p!LaR.8]
return countType; u&Xn#fh
} a/q8v P
public int getCountId(){ +\B.3%\-
return countId; u9}LvQh_6,
} Uv:NY1(3!
} AT^MQvn
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CountCache.java =:^f6"p&Z
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/* N!af1zj
* CountCache.java iS8yJRy
* u,S}4p&l
* Created on 2007年1月1日, 下午5:01 2C&l\16
* o2riy'~
* To change this template, choose Tools | Options and locate the template under 3q (]Dg;v
* the Source Creation and Management node. Right-click the template and choose 5[$Tpn#K7
* Open. You can then make changes to the template in the Source Editor. XV<{tqa
*/ } q r
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package com.tot.count; >56;M7b(K
import java.util.*; 5AAPtZ\lH
/** [iG4qI
* URxy*)
* @author {F$MZ2 E
*/ G c:oSvm
public class CountCache { &G!2T!xx
public static LinkedList list=new LinkedList(); MB(l*ju0
/** Creates a new instance of CountCache */ ! lm0zR
public CountCache() {} ^: V6=
public static void add(CountBean cb){ (qy82F-|2
if(cb!=null){ naW!Mga
list.add(cb); TSYe~)I
} @{^6_n+gT%
} X7 fJ+Cn
} sJ cwN.s
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CountControl.java h<f]hJ`ep
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/* IqmQQ_KH
* CountThread.java x5nw/''[2
* 2/G`ej!*
* Created on 2007年1月1日, 下午4:57 \}})U#
* A/U, |
* To change this template, choose Tools | Options and locate the template under ?Kf?Z`9 *Y
* the Source Creation and Management node. Right-click the template and choose "0A !fRI~
* Open. You can then make changes to the template in the Source Editor. L+$9 ,<'[
*/ T! fF1cpF\
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package com.tot.count; !T8h+3I
import tot.db.DBUtils; 9^1.nE(R&
import java.sql.*; yBxWBW*e
/** nQ^<h.
* }Dc?Emb
* @author |R$/oq
*/ p7Q
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public class CountControl{ d+:pZ
private static long lastExecuteTime=0;//上次更新时间 M8'
GbF=1
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 sAU!u
/** Creates a new instance of CountThread */ ;b1*2-
public CountControl() {} !8i[.EAT
public synchronized void executeUpdate(){ Sg}]5Mn`
Connection conn=null; aJ}Cqk
PreparedStatement ps=null; FrBJv<
try{ C@[f Z
conn = DBUtils.getConnection(); `}9j vR5
conn.setAutoCommit(false); SPK%
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); O
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for(int i=0;i<CountCache.list.size();i++){ F~_)auH
CountBean cb=(CountBean)CountCache.list.getFirst(); H-aSLc
CountCache.list.removeFirst(); 8HymkL&F
ps.setInt(1, cb.getCountId()); [>tyx{T Ye
ps.executeUpdate();⑴ ~%o?J"y
//ps.addBatch();⑵ {Deg1V!x>
} %4rPkPAtrp
//int [] counts = ps.executeBatch();⑶ n9Xs sl0
conn.commit(); ;F!wyTF>}
}catch(Exception e){ rG|*74Q]
e.printStackTrace();
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} finally{ 3d@$iAw1<
try{ w$5#jJX\
if(ps!=null) { ;^j2>Azn
ps.clearParameters(); <MH| <hP
ps.close(); 5+[`x']l
ps=null; SXx2
} Nn;p1n
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}catch(SQLException e){} 'cx&:s
DBUtils.closeConnection(conn); g5*Zg_G/
} zT5@wm
} iB,Nqs3i*
public long getLast(){ u.s-/ g
return lastExecuteTime; 9e|]H+y
} ^"!j m
public void run(){ ]M;aVw<!
long now = System.currentTimeMillis(); tzeS D C
if ((now - lastExecuteTime) > executeSep) { aN5 w
//System.out.print("lastExecuteTime:"+lastExecuteTime); V:w=h>z8
//System.out.print(" now:"+now+"\n"); Iv5agh%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); hh!^^emo
lastExecuteTime=now; .w `1;o
executeUpdate(); aI6fPQe
} ['SZe0
else{ okO^/"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); k*8
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} HjO-6F#s
} u~9gR @e2{
} L[Dr[
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 FM3DJ?\L-
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类写好了,下面是在JSP中如下调用。 W1
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<% KF"&9nB
CountBean cb=new CountBean(); >6(91J
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )NwIEk>Tf
CountCache.add(cb); |hprk-R*OH
out.print(CountCache.list.size()+"<br>"); k2xOu9ncEj
CountControl c=new CountControl(); '}D$"2I*
c.run(); ^=nJ,-(h_
out.print(CountCache.list.size()+"<br>"); rU/V~;#%
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