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: 3U_2! zF3_
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CountBean.java da)NK!
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/* M1KqY: 9E
* CountData.java xhcK~5C
* vWGwVH/K
* Created on 2007年1月1日, 下午4:44 r@ZJ{4\Q
* u\eEh*<7q
* To change this template, choose Tools | Options and locate the template under e=O,B8)_
* the Source Creation and Management node. Right-click the template and choose */|BpakD<
* Open. You can then make changes to the template in the Source Editor. yj^+G
*/ $56,$K`H
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package com.tot.count; ai0XL}!+
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/** rRFhGQq1m
* D_vbSF)
* @author 'C"9QfK
*/ /Q~i~B 2j-
public class CountBean { D9M:^
private String countType; s6>ZREf#J
int countId; =:~R=/ZXk
/** Creates a new instance of CountData */ KEWTBBg
public CountBean() {} >,td(= :
public void setCountType(String countTypes){ jy'13G/b\
this.countType=countTypes; z[Xd%mhjO
} P#AW\d^"B
public void setCountId(int countIds){ TqnTS0fx
this.countId=countIds; /~3r;M
} H)n9O/u
public String getCountType(){ aA,!<^&}
return countType; K.0:C`C
} Hw4%uS==V
public int getCountId(){ 1YH+d0UGn
return countId; x)@G;nZ
} w!D|]LoE
} 55z]&5N
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CountCache.java 0=?<y'=
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/*
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* CountCache.java t2)rUWg
* 5k.oW=
* Created on 2007年1月1日, 下午5:01 ~;N^g4s
* >Z5gSs0
* To change this template, choose Tools | Options and locate the template under :\|SQKD
* the Source Creation and Management node. Right-click the template and choose 9E6_]8rl
* Open. You can then make changes to the template in the Source Editor. `E>1>'
*/ Ig
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package com.tot.count; P}4QQw
import java.util.*; .4E&/w+
/** .nVa[B|.
* BBev<
* @author T
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*/ 7Ve1]) u
public class CountCache { a*&B`77`|
public static LinkedList list=new LinkedList(); JT!9\i
/** Creates a new instance of CountCache */ sr{a(4*\
public CountCache() {} 6}!#;@D~
public static void add(CountBean cb){ Eqj_m|@
if(cb!=null){ rogT~G}q
list.add(cb); Rx}$0c0
} 2I,^YWR
} .?loO3 m
} :s7m4!EF
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CountControl.java &__es{;P
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/* y#3j`. $3p
* CountThread.java GU( _
* `)_dS&_\
* Created on 2007年1月1日, 下午4:57 r2,.abo
* N(Fp0
* To change this template, choose Tools | Options and locate the template under Tu).K.p:
* the Source Creation and Management node. Right-click the template and choose AHX St
* Open. You can then make changes to the template in the Source Editor. LhA/xf
*/ pu2tY7Ja
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package com.tot.count; @}}$zv6l,
import tot.db.DBUtils; ;6>2"{NW
import java.sql.*; ]7Tkkw$
/** '/^qJ7eb
* 7+\+DujE$
* @author =4FXBPoQK
*/ ;wz^gdh;
public class CountControl{ Utnr5^].2O
private static long lastExecuteTime=0;//上次更新时间 SAy=WV
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 e&&53?
/** Creates a new instance of CountThread */ BRgXr
public CountControl() {} JvVWG'Z"
public synchronized void executeUpdate(){ cj$[E]B3V*
Connection conn=null; UG+d-&~Ll
PreparedStatement ps=null; 5kCUaPu
try{ v|dBSX9k0
conn = DBUtils.getConnection(); 6WXRP;!Q
conn.setAutoCommit(false); CxwoBuG=?
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `erV$( M
for(int i=0;i<CountCache.list.size();i++){ /`wvxKX
CountBean cb=(CountBean)CountCache.list.getFirst(); PHZ0P7
CountCache.list.removeFirst(); @~^5l
ps.setInt(1, cb.getCountId()); J IUx
ps.executeUpdate();⑴ JB<Sl4
//ps.addBatch();⑵ um!J]N^
} Rh_np
//int [] counts = ps.executeBatch();⑶ O$_)G\\\m
conn.commit(); ]>=}*=
}catch(Exception e){ /|C*
e.printStackTrace(); -zOdU}91Ao
} finally{ l]Ax : Z
try{ }fb#G<3
if(ps!=null) { +BETF;0D
ps.clearParameters();
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ps.close(); '
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ps=null; $u]jy0X<Y;
} bDL,S?@
}catch(SQLException e){} |H;F7Y_
DBUtils.closeConnection(conn); Qz5sxi
} ZX9T YN
} J;.wXS_U8
public long getLast(){ 4|riKo)
return lastExecuteTime; E8$20Ue
} .F
public void run(){ "{@A5A
long now = System.currentTimeMillis(); 9K{%vK
if ((now - lastExecuteTime) > executeSep) { 6e9,PS
//System.out.print("lastExecuteTime:"+lastExecuteTime); I>]oS(GNT
//System.out.print(" now:"+now+"\n"); lr>oYS0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 5m\<U`
lastExecuteTime=now; 8']M^|1
executeUpdate(); e7Xeo +/
} 6#7Lm) g8
else{ m$}R%
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); KL1/^1
} \^L`7cBL
} 8 OY 3A
} ]zE;Tw.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 RYQ<Zr$!
#@YPic"n7`
类写好了,下面是在JSP中如下调用。 b=yx7v"r
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<% uki#/GzaO
CountBean cb=new CountBean(); +ga k#M"n\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); HHDl8lo
CountCache.add(cb); vQosPS_2L
out.print(CountCache.list.size()+"<br>"); \?[v{WP)
CountControl c=new CountControl(); LClNxm2X
c.run(); cv998*|X:
out.print(CountCache.list.size()+"<br>"); Ktb\ b w
%>