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: #![i
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CountBean.java j.GpJDq
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/* 4QnJ;&~
* CountData.java Pl=X<Bp
* OC'cP[$ _
* Created on 2007年1月1日, 下午4:44 H~c+L'=
* {PHxm
* To change this template, choose Tools | Options and locate the template under ybtje=3E
* the Source Creation and Management node. Right-click the template and choose }6P]32d
* Open. You can then make changes to the template in the Source Editor. |52VHW8c
*/ vm+EzmO,!
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package com.tot.count; _Gy*" ;E
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/** GYiUne$
*
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* @author ;o\0:fzr
*/ [IxZweK
public class CountBean { #(@dN+
private String countType; 1$fA9u$
int countId; apUV6h-v
/** Creates a new instance of CountData */ m p~\ioI*d
public CountBean() {} ushQWP)
public void setCountType(String countTypes){ t=~5I>
this.countType=countTypes; nTjQ4y
} .1MXQLy
public void setCountId(int countIds){ |pr~Ohz
this.countId=countIds; 0[0</"K%1m
} ^HKxaW9W
public String getCountType(){ vKDPg p<j
return countType; 8oY0?|_Bx
} {S\cpCI`
public int getCountId(){ C+}uH:I'L
return countId; J3Q.6e=7
} SSi}1
} Dw{C_e
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CountCache.java xYM!mcA
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/* _y`'T;~OY
* CountCache.java A0S6 4(
* 94W9P't
* Created on 2007年1月1日, 下午5:01 -4b9(
* qwA:o-q"
* To change this template, choose Tools | Options and locate the template under kaUH#;c>_
* the Source Creation and Management node. Right-click the template and choose 4 !~JNO
* Open. You can then make changes to the template in the Source Editor. ;4XX8W1
*/ XLFJ?$)Tro
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package com.tot.count; hdN3r{
import java.util.*; \u,hS*v0
/** uZ Id.+Rk
* (XT^<#Ga
* @author Kd;|Z
*/ qX:54$t
public class CountCache { O" ['.b
public static LinkedList list=new LinkedList(); +S|y)W8
/** Creates a new instance of CountCache */ E](Ood
public CountCache() {} w0moC9#$?
public static void add(CountBean cb){ _}`iLA!$I
if(cb!=null){ y{K~g<VL
list.add(cb); ZWmmFKFG.
} ?mRU9VY
} ^']xkS
} L3X>v3CZ5
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CountControl.java UX2`x9
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/* Vjj30f
* CountThread.java |??uVA)\X
* sqac>v
* Created on 2007年1月1日, 下午4:57 |;{wy
* 7Y@&&
* To change this template, choose Tools | Options and locate the template under Uh?SDay
* the Source Creation and Management node. Right-click the template and choose wp.<}=|u
* Open. You can then make changes to the template in the Source Editor. h{J2CWJ
*/ ] 2FS=
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package com.tot.count; .0.Ha}{6b
import tot.db.DBUtils; zWB>;Z}
import java.sql.*; ~2V|]Y;s
/** #=7~.Y
* |53Zg"!
* @author mWUQF"q8
*/ ph%/;?wY
public class CountControl{ QF'N8Kla
private static long lastExecuteTime=0;//上次更新时间 =|pQA~UU#
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 M<~z=B#
/** Creates a new instance of CountThread */ MBXumc_g
public CountControl() {} o}7`SYn
public synchronized void executeUpdate(){ [=7|LHjU
Connection conn=null; "ln(EvW
PreparedStatement ps=null; vDv:3qN7(
try{ jUI'F4.5x-
conn = DBUtils.getConnection(); e6QUe.S
conn.setAutoCommit(false); &JtK<g
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [$;6LFs}
for(int i=0;i<CountCache.list.size();i++){ m+"?;;s
CountBean cb=(CountBean)CountCache.list.getFirst(); _rY,=h{+
CountCache.list.removeFirst(); \;.\g6zX
ps.setInt(1, cb.getCountId()); ,g6w2y7 ]
ps.executeUpdate();⑴ ^6Hfq^ejt
//ps.addBatch();⑵ E
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} +i4S^B/8i
//int [] counts = ps.executeBatch();⑶ kDS4 t?Ig
conn.commit(); D7olu29
}catch(Exception e){ Ym8G=KA
e.printStackTrace(); 506B=
} finally{ a:XVu0`(
try{ !\z:S?V
if(ps!=null) { cX>
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ps.clearParameters(); $[by)
ps.close(); 8G6PcTqv"
ps=null; ?76Wg::
} g>1yQ
}catch(SQLException e){} #Ne<=ayS
DBUtils.closeConnection(conn); \rF6"24t6
} |ITp$_S
} X2}\i5{
public long getLast(){ q?nXhUD
return lastExecuteTime; [}9sq+##
} +\fr3@Yc
public void run(){ \3-XXq
long now = System.currentTimeMillis(); ra0:Lg'
if ((now - lastExecuteTime) > executeSep) { m$ )yd~
//System.out.print("lastExecuteTime:"+lastExecuteTime); o8-BTq8
//System.out.print(" now:"+now+"\n"); 8V`NQS$
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); w9rwuk
lastExecuteTime=now; h3Nwxj~E
executeUpdate(); @{iws@.
} j 6%X
else{ 1XSA3;ZEc
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &=Gz[1
L
} jrbEJ.
} W2D^%;mw
} GpMKOjVm|
//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 o]t6u .L
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类写好了,下面是在JSP中如下调用。 gbsRf&4h
OL4I}^*,
<% !
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CountBean cb=new CountBean(); 1P.
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^VK-[Sz&
CountCache.add(cb); :9Zu&t
out.print(CountCache.list.size()+"<br>"); kT&-:: ^R
CountControl c=new CountControl(); UCj4%y6t
c.run(); Zf68EB
out.print(CountCache.list.size()+"<br>"); 1L]7*NJe
%>