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: z<u@::
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CountBean.java *?!A
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/* puK /;nns
* CountData.java Ql9
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* #IxCI)!I{[
* Created on 2007年1月1日, 下午4:44 $`txU5#vs
* #4{9l
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* To change this template, choose Tools | Options and locate the template under }^ZPah
* the Source Creation and Management node. Right-click the template and choose 2rqYm6
* Open. You can then make changes to the template in the Source Editor. Y4)=D@JI
*/ 2^fSC`!
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package com.tot.count; qViolmDz
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/** KTjf2/
* _;u@xl=
* @author e2Df@8>
*/ O^4Ko}
public class CountBean { )5l9!1j
private String countType; UP@-@syGw
int countId; g({dD;
/** Creates a new instance of CountData */ Y-G;;~
public CountBean() {} K2ry@haN
public void setCountType(String countTypes){ 8p.O rdp
this.countType=countTypes; "uD^1'IW2
} Zl7m:b2M
public void setCountId(int countIds){ ym6gj#2m
this.countId=countIds; QE~#eo
} Gu\lV c
public String getCountType(){ c{cJ>d 0
return countType; vY(xH>Fd
}
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public int getCountId(){ b;$jh
return countId; &&($LnyA]
} `KJBQK
} =@go;,"
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CountCache.java P[a\Q`}L
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/* Wj#Gm
* CountCache.java r$z0C&5
* AV^Sla7|_
* Created on 2007年1月1日, 下午5:01 F<N{ x^
* I:,D:00+
* To change this template, choose Tools | Options and locate the template under 3qBZzM
O*
* the Source Creation and Management node. Right-click the template and choose @M ]7',2"
* Open. You can then make changes to the template in the Source Editor. yf7$m_$C'
*/ i*Ee(m]I
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package com.tot.count; |\S p IFH1
import java.util.*; b+ J)
/** Vq1ve;(8s
* kc-v(WIC
* @author 1U;p+k5c
*/ pm}!?TL
public class CountCache { j?'It`s
public static LinkedList list=new LinkedList(); ET}Dh3A
/** Creates a new instance of CountCache */ 4^Ghn
public CountCache() {} :s`\jJ
public static void add(CountBean cb){ _T[m YY
if(cb!=null){ _ya_Jf*
list.add(cb); 0s8w)%4$
} ZdY)&LJ
} l-RwCw4f
} "1Oe
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CountControl.java FZ^j|2.L*
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/* 9`p|>d!.
* CountThread.java dSm; e_s
* ULIpb
* Created on 2007年1月1日, 下午4:57 ESt@%7.F
* Zqnwf
* To change this template, choose Tools | Options and locate the template under x-HN]quhe
* the Source Creation and Management node. Right-click the template and choose x)Ls(Xh+g
* Open. You can then make changes to the template in the Source Editor. vZl]C%
*/ qg#|1J6e
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package com.tot.count; +>wBGVvS
import tot.db.DBUtils; e4/Y/:vFO
import java.sql.*; 5T4!'4n
/** ET 2@dY~
* NLA/XZ
* @author W6 U**ir.
*/ `c~J&@|
public class CountControl{ w
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private static long lastExecuteTime=0;//上次更新时间 zs~v6y@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 k2cC:5Xf3
/** Creates a new instance of CountThread */ (+ibT;!]
public CountControl() {} ~t-!{F
public synchronized void executeUpdate(){ Vy7o}z`
Connection conn=null; eAD uk!Iq
PreparedStatement ps=null; j"c30AY
try{ :v>Nz7SB
conn = DBUtils.getConnection(); t}]R0O.s
conn.setAutoCommit(false); qoXncdDHZ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); HM(S}>
for(int i=0;i<CountCache.list.size();i++){ Gn8'h
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CountBean cb=(CountBean)CountCache.list.getFirst(); 1||\3L/
CountCache.list.removeFirst(); lEe<!B$d"
ps.setInt(1, cb.getCountId()); +__PT4ps
ps.executeUpdate();⑴ ^<VJ8jk<
//ps.addBatch();⑵ [|!A3o
} K7CrRT3>6
//int [] counts = ps.executeBatch();⑶ IDIok~B=e
conn.commit(); M'D l_dx-
}catch(Exception e){ J@vL,C)E6
e.printStackTrace(); t5Oeb<REz
} finally{ O.% $oV
try{ :]hNw1e
if(ps!=null) { #7}1W[y9}l
ps.clearParameters(); y:R!E *.L'
ps.close(); 86AZ)UP2D
ps=null; 7}2Aq
} B<" `<oG@|
}catch(SQLException e){} M)JKe!0ad1
DBUtils.closeConnection(conn); ,s9gGCA
} A3|hFk
} :_f5(N*{5o
public long getLast(){ \6)]!$F6:
return lastExecuteTime; GZwz4=`
} o'SZsG
public void run(){ (:P-ef$]C
long now = System.currentTimeMillis(); Q`kJ3b
if ((now - lastExecuteTime) > executeSep) { v?=y9lEH@%
//System.out.print("lastExecuteTime:"+lastExecuteTime); mhDC1lXF
//System.out.print(" now:"+now+"\n"); i=^!?
i
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); J )DFH~p
lastExecuteTime=now; 74p=uQ
executeUpdate(); DQy<!Wb+
} bk}'wcX<+]
else{ p9`!.~[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -E(0}\
} zv8AvNDK
} Sd |=*X
} ._i|+[
//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 15X.gx
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类写好了,下面是在JSP中如下调用。 ~]_U!r[FA
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<% ;LXwW(_6d
CountBean cb=new CountBean(); 6B=: P3Y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Sr#\5UDS
CountCache.add(cb); p"UdD
out.print(CountCache.list.size()+"<br>"); !JGe
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CountControl c=new CountControl(); e>] gCa
c.run(); psFY=^69o
out.print(CountCache.list.size()+"<br>"); };Oyv7D+b
%>