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: {yHB2=nI
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CountBean.java ;c X^8;F0
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/* OY^n0Zof,
* CountData.java -eR!qy:.]5
* DrCWvpudd
* Created on 2007年1月1日, 下午4:44 :otY;n -
* [W9e>Nsp0
* To change this template, choose Tools | Options and locate the template under V5u}C-o
* the Source Creation and Management node. Right-click the template and choose 4+5OR&kxZ
* Open. You can then make changes to the template in the Source Editor. [ZKtbPHb
*/ GX7 eRqz >
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package com.tot.count; bB;~,W&E1
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/** *>aZc::
* U0h)pdo
* @author T2:oWjC3$
*/ 8tLT'2+H#
public class CountBean { {=bg5I0|a
private String countType; ]&C:>
int countId; FDF3zzP0
/** Creates a new instance of CountData */ <.r ]dCf
public CountBean() {} qe5tcv}u
public void setCountType(String countTypes){ stg30><
this.countType=countTypes; >'} Y1_S5
} [y|^P\D
public void setCountId(int countIds){ T_@[k
this.countId=countIds; p.rdSv(8'
} mUrS&&fu8
public String getCountType(){ !2zo]v4?
return countType; FJsK5-
} ?kL|>1TY
public int getCountId(){ 1V|< A
return countId; ( zn_8s
} 5q5 )uv"
} Q7~'![(a
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CountCache.java tt6.
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/* MAE7A"la
* CountCache.java {D_++^
* xSpMyXrQ
* Created on 2007年1月1日, 下午5:01 g08*}0-k
* qri}=du&F
* To change this template, choose Tools | Options and locate the template under eJU;*] xfH
* the Source Creation and Management node. Right-click the template and choose .'t (-eT,
* Open. You can then make changes to the template in the Source Editor. 2BoFyL*
*/ bz,Da
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package com.tot.count; ,wtFs!8
import java.util.*; 5^/,aI
/** E4sn[DO
* J)9 AnGWe
* @author pN\)(:"8v
*/ 9W{,=.%MX$
public class CountCache { CfPXn0I
public static LinkedList list=new LinkedList(); V";mWws+?#
/** Creates a new instance of CountCache */ )KSisEL
public CountCache() {} :/o C:z\h
public static void add(CountBean cb){ { 1+Cw?1d
if(cb!=null){ A",eS6
list.add(cb); ]b4pI*:$I
} Ik`O.Q.}
} <8u>_o6
} o3Mf:;2c C
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CountControl.java k$ZRZ{
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/* 99 <4t$KH
* CountThread.java E%<w5d.lq
* vuYO\u+ud
* Created on 2007年1月1日, 下午4:57 N]B)Fb
* w Y8@1>ah
* To change this template, choose Tools | Options and locate the template under a?5WKO
* the Source Creation and Management node. Right-click the template and choose uQH%.A
* Open. You can then make changes to the template in the Source Editor. kUNj4xp)
*/ Ct4LkmD
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package com.tot.count; 2>F\&
import tot.db.DBUtils; KMUK`tbaI
import java.sql.*; FX
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/** ,"~WkLI~\t
* TQ;
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* @author /_]ltX D
*/ *8z"^7?^=
public class CountControl{ [/
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private static long lastExecuteTime=0;//上次更新时间 I[}75:^Rt
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?q\FLb%"7
/** Creates a new instance of CountThread */ %dEB /[
public CountControl() {} 7=}6H3|&
public synchronized void executeUpdate(){ 4HM;K_G%{
Connection conn=null; +T9Q_e*
PreparedStatement ps=null; eymi2-a<
try{ k/% #>
conn = DBUtils.getConnection(); 7; p4Wg7k}
conn.setAutoCommit(false); F "!agc2!
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +wipfL~&S
for(int i=0;i<CountCache.list.size();i++){ TYYp"wx
CountBean cb=(CountBean)CountCache.list.getFirst(); G 0hYFc u
CountCache.list.removeFirst(); @&;(D!_&
ps.setInt(1, cb.getCountId()); Z+ixRch@-s
ps.executeUpdate();⑴ v2d<o[[C
//ps.addBatch();⑵ ?-pi,O~(p
} BWWq4mdb{
//int [] counts = ps.executeBatch();⑶ hw;0t,1
conn.commit(); 'iJDWxCD
}catch(Exception e){ =/[ltUKs:a
e.printStackTrace(); JjQ8|En
} finally{ T'E]
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try{ 2+z1h^)W
if(ps!=null) { )B6# A0
ps.clearParameters(); 1!vPc93 $$
ps.close(); 4CLsY n?
ps=null; n=q=zn;
} ?]^zD k@~
}catch(SQLException e){} @<2d8ed
DBUtils.closeConnection(conn); Bz?l{4".
} c7\VTYT
} zxkM'8JC
public long getLast(){ K}x_nW
return lastExecuteTime; 1pK6=-3w3
} ^K+:C;Q|
public void run(){ |XRImeF'd
long now = System.currentTimeMillis(); v,{h:
if ((now - lastExecuteTime) > executeSep) { KF_ ?'X0=
//System.out.print("lastExecuteTime:"+lastExecuteTime); %`e`g ^
//System.out.print(" now:"+now+"\n"); Mi]I:ka
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); (?vK_{
lastExecuteTime=now; 8!&nKy<Y
executeUpdate(); $xT1 1 ^
} D|l,08n"?
else{ r4u z} jl{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X1oGp+&
} n#4Gv|{XMD
} I.1D*!tz
} Y6A;AmM8
//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 t0q_>T-kt
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类写好了,下面是在JSP中如下调用。 i\)3l%AK]T
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<% b._m 8z ~
CountBean cb=new CountBean(); m[spn@SF
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #n3ykzoqIX
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); >.e+S?o
CountControl c=new CountControl(); \7Qb229?
c.run(); 'f+NW&
out.print(CountCache.list.size()+"<br>"); )s)_XL
%>