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: 4HGR-S/
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CountBean.java ]pVuRj'pP
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/* (T.g""N~`
* CountData.java D:N\K/p
* pEb/ yIT"
* Created on 2007年1月1日, 下午4:44 36 ]?4, .
* z_Pq5
* To change this template, choose Tools | Options and locate the template under qqu]r
* the Source Creation and Management node. Right-click the template and choose LO)QEUG
* Open. You can then make changes to the template in the Source Editor. zR}vR9Ls
*/ tz%H1`
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package com.tot.count; t&G #%
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/** ^pocbmg
* OX.g~M
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* @author ?"p.Gy)
*/ 74KR.ABd
public class CountBean { Z%VgAV>>
private String countType; {XLRrU!*
int countId; XeAH.i<
/** Creates a new instance of CountData */ rX|{nb
public CountBean() {} HB}iT1.`
public void setCountType(String countTypes){ x0q`Uc
this.countType=countTypes; Ntpw(E<$f
} sg_%=;
public void setCountId(int countIds){ 9]a!1
this.countId=countIds; 0}$R4<"{Y>
} er>@- F7w
public String getCountType(){ v+d? #^
return countType; MAgoxq~;V
} n<>]7-
public int getCountId(){ K- TLzoYA
return countId; en16hd>^W:
} AD"L>7
} &3YXDNm
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CountCache.java 9:*a9xT,
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/* G}'\
* CountCache.java b*cVC^{Dy
* 51!#m|
* Created on 2007年1月1日, 下午5:01 <+ckE2j
* 5Ja[p~^L
* To change this template, choose Tools | Options and locate the template under G 2FD'Sf
* the Source Creation and Management node. Right-click the template and choose 2L7ogyrU/A
* Open. You can then make changes to the template in the Source Editor. PE2O$:b\
*/ U~<~>^[
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package com.tot.count; w?M` gl8r
import java.util.*; >jm^MS=
/** !JPZ7_nn
* qD5)AdCGO
* @author F6
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*/ #!]~E@;E
public class CountCache { [vcSt5R=
public static LinkedList list=new LinkedList(); 3xpygx9
/** Creates a new instance of CountCache */ `FIS2sl/
public CountCache() {} mUwGr_)wj
public static void add(CountBean cb){ A55F *d
if(cb!=null){ 1h&_Q}DM
list.add(cb); r-c1_
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} pt9fOih[
} 5m
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} \Oa11c`6
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CountControl.java wL"
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/* RVa{%
* CountThread.java EdS7m,d
* Hr;\}
* Created on 2007年1月1日, 下午4:57 ~{np G
* $R/@%U)-o
* To change this template, choose Tools | Options and locate the template under WD?COUEox
* the Source Creation and Management node. Right-click the template and choose 4Pr@<S"U
* Open. You can then make changes to the template in the Source Editor. -y)g}D%
*/ OG2&=~hOz-
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package com.tot.count; F!ra$5u
import tot.db.DBUtils; @i@f@.t
import java.sql.*; r_M5:Rz
/** hE}y/A[
* 4>te>[
* @author NpF)|Ppb{
*/ P<IZ%eS3B
public class CountControl{ 5t[7taLX\
private static long lastExecuteTime=0;//上次更新时间 ^
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ bODyJ7=[
public CountControl() {} z irnur1
public synchronized void executeUpdate(){ _qq>-{-Ym
Connection conn=null; 2p8}6y:}7
PreparedStatement ps=null; ,M$J
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try{ 5*r5?ne
conn = DBUtils.getConnection(); {@T<eb$d
conn.setAutoCommit(false); >D*%1LH~V
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,HfdiGs}j
for(int i=0;i<CountCache.list.size();i++){ R ;3!?`
CountBean cb=(CountBean)CountCache.list.getFirst(); -5Ln3\ O@
CountCache.list.removeFirst(); 7B#HF?,?
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ &8QkGUbS<
//ps.addBatch();⑵ j'nrdr6n
} j+NpQ}t:
//int [] counts = ps.executeBatch();⑶ !9. `zW"40
conn.commit(); ;2iDa
}catch(Exception e){ SSa0x9T
e.printStackTrace(); ?E.MP7Y#V
} finally{ A>QAR)YP
try{ -bQi4
if(ps!=null) { 6ragRS/'x
ps.clearParameters(); G0pqiU6
ps.close(); A=pyaU`aE
ps=null; TvwkeOS#}7
} .0#{?R,
}catch(SQLException e){}
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DBUtils.closeConnection(conn); bDM;7fFp$
} :V:siIDn
} 5D`!Tu3
public long getLast(){ R(<_p"9(
return lastExecuteTime; 6gJc?+
} gL6.,4q+1
public void run(){ !eGUiE=
long now = System.currentTimeMillis(); Ihg1%.^V\
if ((now - lastExecuteTime) > executeSep) { y_N h5
//System.out.print("lastExecuteTime:"+lastExecuteTime); PW GNUNc
//System.out.print(" now:"+now+"\n");
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?/^x)Nm
lastExecuteTime=now; C+Pw
executeUpdate(); lsRW.h,
} S]}W+BF3
else{ 2U`g[1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); `NARJ9M
} =1Tn~)^O
} wb/@g=`d
} eAbp5}B
//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
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类写好了,下面是在JSP中如下调用。 q;H5S<]/
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<% n%={!WD
CountBean cb=new CountBean(); [,|;rt\o>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `& }C*i"
CountCache.add(cb); }-15^2
out.print(CountCache.list.size()+"<br>"); JzuP AI
CountControl c=new CountControl(); T,fDH!a
c.run(); U~YjTjbd
out.print(CountCache.list.size()+"<br>"); H4JwgQ
%>