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: ^%OH}Z `ly
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CountBean.java !\k#{
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/* {ZIFj.2
* CountData.java Mp@(/
* hjp?/i%TQ
* Created on 2007年1月1日, 下午4:44 FLnAN;
* @XG`D>%k
* To change this template, choose Tools | Options and locate the template under +sbacMfq
* the Source Creation and Management node. Right-click the template and choose [,A'
* Open. You can then make changes to the template in the Source Editor. m"m;(T{ v
*/ h}:5hi Jw
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package com.tot.count; !VZCM{
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/** Nm:<rI,^
* N, +g/o\f
* @author #1!BD!u
*/ ^fiRRFr[
public class CountBean { md
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private String countType; czsoD)N
int countId; C"|_j?
/** Creates a new instance of CountData */ d@`:9
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public CountBean() {} z^HlDwsbm
public void setCountType(String countTypes){ 8RT0&[
this.countType=countTypes; 0}C}\1
} (Gk]<`d#N
public void setCountId(int countIds){ G@I_6cE
this.countId=countIds; x 3co?
} _nFvM'`<
public String getCountType(){ J1ro\"
return countType; 2F@<{v4
} OuIW|gIu0
public int getCountId(){ cz~11j#
return countId; Ecl7=-y
} 2+Y`pz47W
} [Ik
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CountCache.java PaI63 !
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/* 9d(v^T
* CountCache.java <EN[s
* (2(;u1
* Created on 2007年1月1日, 下午5:01 &$Ip$"H
* 2<. /HH*f
* To change this template, choose Tools | Options and locate the template under ;}9Ws6#XQs
* the Source Creation and Management node. Right-click the template and choose ^p%+r B.j[
* Open. You can then make changes to the template in the Source Editor. q9z!g/,d/
*/ zyn =Xv@p
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package com.tot.count; w3|.4hS
import java.util.*; hfa_M[#Q-
/** E1Aa2
* _~&vs<
* @author en6AAr:U}
*/ w)SxwlW}
public class CountCache { _Wsk3AP
public static LinkedList list=new LinkedList(); \D k^\-
/** Creates a new instance of CountCache */ =y/Lbe}:
public CountCache() {} h pes
public static void add(CountBean cb){ |N.q[>^R
if(cb!=null){ Bq=](<>>
list.add(cb); 4~MUc!
} w}<I\*\`!
} x(6.W"-S
} 7Ki7N{Kt
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CountControl.java ]`U?<9~Ob
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/* 7uH{UpslJ
* CountThread.java T $]L 5
* >a~FSZf
* Created on 2007年1月1日, 下午4:57 \V\ET
* 'QS~<^-j"
* To change this template, choose Tools | Options and locate the template under APm[)vw#f
* the Source Creation and Management node. Right-click the template and choose =U|SK"oO
* Open. You can then make changes to the template in the Source Editor. cDol
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*/ |L-juT X9
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package com.tot.count; .5 r0%
import tot.db.DBUtils; A+*(Pds
import java.sql.*; GB Un" _J
/** ?Og ;W9i
* NGGd6V%'-
* @author !Bbwl-e`
*/ :iiTz$yk
public class CountControl{ bvvx(?!
private static long lastExecuteTime=0;//上次更新时间 2;7GgO~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 S(s~4(o>8
/** Creates a new instance of CountThread */ Z'M@DY/fdK
public CountControl() {} O@&I.d$
public synchronized void executeUpdate(){ tELnq#<6
Connection conn=null; 56aJE
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PreparedStatement ps=null; I4ct``Di
try{ :dc
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conn = DBUtils.getConnection(); u3!!_~6,z
conn.setAutoCommit(false); z1A-EeT
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /'+JP4mK
for(int i=0;i<CountCache.list.size();i++){ @}RyW&1Z
CountBean cb=(CountBean)CountCache.list.getFirst(); 2xm?,p`
CountCache.list.removeFirst(); 3{E}^ve
ps.setInt(1, cb.getCountId()); Mi-9sW
ps.executeUpdate();⑴ \"j1fAD!
//ps.addBatch();⑵ }('QIvq2
} RtEkd_2
//int [] counts = ps.executeBatch();⑶ l'R`XGT
conn.commit(); 88U
}catch(Exception e){ (jMp`4P
e.printStackTrace(); }Ec"&
} finally{ GY :IORuA4
try{ Ghe=hhZ
if(ps!=null) { ai2}vR
ps.clearParameters(); 7nIMIkT:
ps.close(); ZS;kCdL
ps=null; -^N '18:
} 7:<>#
}catch(SQLException e){} Ds/zl Z
DBUtils.closeConnection(conn); mJqP#Unik
} =~*u(0sJa
} Y^f|}YO%y
public long getLast(){ K|!)<6ZsG7
return lastExecuteTime; -v&srd^
} V!!'S
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public void run(){ 6?~pjMV
long now = System.currentTimeMillis(); N|d@B{a(
if ((now - lastExecuteTime) > executeSep) { |mX8fRh
//System.out.print("lastExecuteTime:"+lastExecuteTime); C*<LVW{P
//System.out.print(" now:"+now+"\n"); |a3b2x,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }e w?{
lastExecuteTime=now; _"TG:RP
executeUpdate(); QY!A[!6h
} =^}2 /vA
else{ u^9,u/gj
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 81g0oVv
} evP`&23tP
} CjCnh7tm
} W5 }zJ)x
//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 m 9Q{)?J7
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类写好了,下面是在JSP中如下调用。 Ha\ hQ'99
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<% 2|EoP-K7
CountBean cb=new CountBean(); ]e9kf$'
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); I}{eYXh
CountCache.add(cb); 0U~JSmj:2K
out.print(CountCache.list.size()+"<br>"); ]|(?i ,p
CountControl c=new CountControl(); <9vkiEo
c.run(); y3GIR
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out.print(CountCache.list.size()+"<br>"); !Zx>)V6.
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