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: #Q@6:bBzv
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CountBean.java I|IlFu?O=
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/* ^R7z LHU;
* CountData.java YB{E=\~
* D:ugP,
* Created on 2007年1月1日, 下午4:44 C5 5n
* ,A!e"=HF
* To change this template, choose Tools | Options and locate the template under \u_v7g
* the Source Creation and Management node. Right-click the template and choose c'+r[rSn1
* Open. You can then make changes to the template in the Source Editor. {}o>nenx\
*/ &E &iaw!
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package com.tot.count; ]A]E)*
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/** H8BO*8}
* ~}0hN]*G
* @author EjX'&"3.
*/ ).!14Gjo
public class CountBean { SfobzX}~Jh
private String countType; n{Qh8"
int countId; ;9 &1JX
/** Creates a new instance of CountData */ \Tf{ui
public CountBean() {} }Q=se[((
public void setCountType(String countTypes){ :z} _y&]
this.countType=countTypes; inv{dg/2
} T{H#]BF<E
public void setCountId(int countIds){ p@8^gc
this.countId=countIds; ]<;i}n|
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} 9h38`*Im;
public String getCountType(){ `{|}LFS>
return countType; qv*uM0G6i
} 2V2x,!
public int getCountId(){ Y5i`pY/}#?
return countId; <,X+`m&
} Ul713Bjz
} BQuliX&
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CountCache.java C3b0`|5
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/* aC8,Y$>?E`
* CountCache.java e7bT%h9i
* R3{*v =ov
* Created on 2007年1月1日, 下午5:01 (LT\
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* BtpjQNN
* To change this template, choose Tools | Options and locate the template under 8/>wgY
* the Source Creation and Management node. Right-click the template and choose spU!t-n67
* Open. You can then make changes to the template in the Source Editor. _czbUl
*/ %j[LRY/
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package com.tot.count; 1Oca@E\Z.
import java.util.*; H7tQ#
/** 5 <)gCHa
* 1IF'>*
* @author /_:T\`5uO
*/ }KD7 Y
public class CountCache { "doU.U&u
public static LinkedList list=new LinkedList(); u_p7Mcb
/** Creates a new instance of CountCache */ D*XZT{1g
public CountCache() {} (ifqwl62
public static void add(CountBean cb){ Wlr&g
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if(cb!=null){ 3I;xU(rv
list.add(cb); ^z *):e
} 0279g
} qlz9&w
} z|G|Y 22
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CountControl.java Y0Hq+7x
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/* a+YR5*&[OO
* CountThread.java Q{.{#G
* xs2,t*
* Created on 2007年1月1日, 下午4:57 F=-uDtQ<N
* g+ >=C
* To change this template, choose Tools | Options and locate the template under H9Y2n 0
* the Source Creation and Management node. Right-click the template and choose RjR&D?dc
* Open. You can then make changes to the template in the Source Editor. inr%XS/m
*/ .6O52E
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package com.tot.count; J{Y6fHFi
import tot.db.DBUtils; &\J?[>EJ.
import java.sql.*; wMH[QYb<*
/** sorSyuGr
* 0On?{Bw
* @author N_u&3CG
*/ F\-B3i%0
public class CountControl{ M>*0r<qn
private static long lastExecuteTime=0;//上次更新时间 1A7 %0/K-]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g9yaNelDh)
/** Creates a new instance of CountThread */ !Y ;H(.A/
public CountControl() {} F[>7z3I
public synchronized void executeUpdate(){ $$haVY&
Connection conn=null; ${A5-
PreparedStatement ps=null; "rme~w Di
try{ Ys"|</;dbj
conn = DBUtils.getConnection(); |A ;o0pL
conn.setAutoCommit(false); f,Sth7y
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !1ML%}vvB,
for(int i=0;i<CountCache.list.size();i++){ E
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CountBean cb=(CountBean)CountCache.list.getFirst(); Yw6DJY
CountCache.list.removeFirst(); vVI6m{zYV
ps.setInt(1, cb.getCountId()); >Y7r\
ps.executeUpdate();⑴ bjPka{PBj
//ps.addBatch();⑵ |ZS 57c:
} U8CWz!;Qz
//int [] counts = ps.executeBatch();⑶ 7cIC&(h5
conn.commit(); UppBnw
}catch(Exception e){ p]wP36<S!
e.printStackTrace(); :|Z$3q
} finally{ uWUR3n
try{ oS~}TR:}
if(ps!=null) { q^Z~IZ8IT
ps.clearParameters(); K1:a]aU?Iu
ps.close(); zL9VR;q
ps=null; wb]*u7G
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} D+f'*|
}catch(SQLException e){} dSwm|kIa
DBUtils.closeConnection(conn); D,MyI#
} kGpV;F==*
} %moJF1
public long getLast(){ k]Zo-xh4
return lastExecuteTime; p?;-!TUv
} ,
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public void run(){ IQT cYl
long now = System.currentTimeMillis(); mKV'jm0
if ((now - lastExecuteTime) > executeSep) { HzE1r+3Q@
//System.out.print("lastExecuteTime:"+lastExecuteTime); _WKJ<dB<
//System.out.print(" now:"+now+"\n"); 4RhR[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 5|{)Z]M%9
lastExecuteTime=now; T'8RkDI}-
executeUpdate(); 2
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} So#dJ>
else{ )!cI|tovs
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :y\09)CJK
} T j`y J!0
} Y&s2C%jT
} 7$
d}!S
//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 z!:'V]
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类写好了,下面是在JSP中如下调用。 @F?=a*s"!
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<% ;`kWpM;
CountBean cb=new CountBean(); ~n6[$WjZA
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =D].`
CountCache.add(cb); %fv)7 CRM
out.print(CountCache.list.size()+"<br>"); >!}`%pk(
CountControl c=new CountControl(); Ib1e#M3
c.run(); !qA8Zky_
out.print(CountCache.list.size()+"<br>"); IZ 8y}2
%>