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: t/_\w"
= l:k($%%
CountBean.java maa$kg8U*!
KoA +Vv9
/* 7w]3D
* CountData.java &8yGV i
* "G,,:H9v
* Created on 2007年1月1日, 下午4:44 :iGK9I
* 6=Wevb5YJ
* To change this template, choose Tools | Options and locate the template under ZpMv16
* the Source Creation and Management node. Right-click the template and choose V(:wYk?ZR
* Open. You can then make changes to the template in the Source Editor. >?_}NZ,y
*/ y^[t3XA6Q
9_4(}|"N|
package com.tot.count; 3t9CN
)*
cucmn*o?
/** -ssmj8:Q\|
* L8H:,} 2
* @author 1wH6 hN,
*/ ^>>9?
public class CountBean { T1R~^x1
private String countType; ~]].i~EV(
int countId; OnhR`
/** Creates a new instance of CountData */ ]*g f$D
public CountBean() {} q/Vl>t
public void setCountType(String countTypes){ cNN0-<#c
this.countType=countTypes; fUfd5W1"
} aOd|;Z
public void setCountId(int countIds){ KJv%t_4'F
this.countId=countIds; !@wUARQ
} cK2;)&U7
public String getCountType(){ Ux{0)"fj
return countType; ZJ~0o2xZ'
} .z=%3p8+
public int getCountId(){ KhP_U{)D
return countId; U&{w:P
} h_\(
$"
} CBNt
_y
mIp> ~
CountCache.java Q2)(tB= )
IOF!Ra:w
/* _sZ&=-FR
* CountCache.java w\UAKN60
* =,C]d~
* Created on 2007年1月1日, 下午5:01 ` AD}6O+x
* edCVIY'1
* To change this template, choose Tools | Options and locate the template under %IE;'aa
}
* the Source Creation and Management node. Right-click the template and choose jKo9y
* Open. You can then make changes to the template in the Source Editor. ; yE.R[I
*/ WPrBK{B`o
o3eaNYa
package com.tot.count; "FhC"}N
import java.util.*; k}I65 ^l#
/** nP<u.{q
L
* <L11s%5-
* @author /hmDePo}
*/ =
Ezg3$%-
public class CountCache { xK)<763q>
public static LinkedList list=new LinkedList(); M2R krW#
/** Creates a new instance of CountCache */ s;E(51V<>
public CountCache() {} W}"tf
L8
public static void add(CountBean cb){ Nd_A8H,&B
if(cb!=null){ eM5-v-
list.add(cb); n%G[Y^^,
} _Pa@%/
} \jV2":[%c
} k.2GIc:5
9;uH}j8sE
CountControl.java u8<[Q]5
8~yP?#p
/* UjLq[,_!
* CountThread.java :Ny[?jtc
* LFqY2,#i
* Created on 2007年1月1日, 下午4:57 evD=]iVD
* !syyOfu`}
* To change this template, choose Tools | Options and locate the template under H=*0KX{
* the Source Creation and Management node. Right-click the template and choose %Y0BPTt$
* Open. You can then make changes to the template in the Source Editor. avM8-&h
*/ )4-!]NsV
`s Im&.d
package com.tot.count; LAM{
,?~
import tot.db.DBUtils; `B&=ya|bl
import java.sql.*; K'e,9P{
/** u"%D;
* It/hXND`
* @author 6v]`s
*/ dZ8ldpf8
public class CountControl{ qT
#=C'?
private static long lastExecuteTime=0;//上次更新时间 ZXkrFA |
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 - US>].
/** Creates a new instance of CountThread */ !.MbPPNp
public CountControl() {} a&2x;diF
public synchronized void executeUpdate(){ _(~LXk^C
Connection conn=null; Y2tBFeWY
PreparedStatement ps=null; ?u;m
],w!
try{ bA2[=6
conn = DBUtils.getConnection(); YlT&.G
conn.setAutoCommit(false); 2TQZu3$c
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %X^qWKix}m
for(int i=0;i<CountCache.list.size();i++){ oR!h
eCnu
CountBean cb=(CountBean)CountCache.list.getFirst(); i%F2^R@!q/
CountCache.list.removeFirst(); Csp$_uDi
ps.setInt(1, cb.getCountId()); =8TBkxG
ps.executeUpdate();⑴ ?(Tin80=r
//ps.addBatch();⑵ =./PY10'
} y`5
?
//int [] counts = ps.executeBatch();⑶ JUj.:n2e
conn.commit(); (CH6Q]Wi_!
}catch(Exception e){ K>LS8,8V
e.printStackTrace(); .iP>?9$f"
} finally{ BB9eQ:
xO
try{ $cuBd
if(ps!=null) { Vr"'O6
ps.clearParameters(); ^+-]V9?+
ps.close(); 5-k gGOt
ps=null; _
W#Km
} &iq'V*+-\
}catch(SQLException e){} WA1yA*S
DBUtils.closeConnection(conn); \ZhkOl
} 0S4Y3bac&
} n[qnrk*3
%
public long getLast(){ @jjxgd'%&
return lastExecuteTime; ,3eN&
} }.U(Gxu$
public void run(){ $bF+J8%D
long now = System.currentTimeMillis(); c+7I
if ((now - lastExecuteTime) > executeSep) { 7J`v#
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;;rx)|\<R
//System.out.print(" now:"+now+"\n"); ^&y*=6C
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); t5S|0/f
lastExecuteTime=now; } _];yw
executeUpdate(); Wd(|w8J{a
} \fSruhD
else{ ]9'F<T= $_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
v0(}"0
} VKu_l
} <0hVDk~
} ubsv\[:C
//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 7bE`P[
i$}G[v<4
类写好了,下面是在JSP中如下调用。 z#|Auc0
lX/7
<% hCc%d$wVk
CountBean cb=new CountBean(); .YH#+T'
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {|j-e{*
CountCache.add(cb); $AvaOI.l
out.print(CountCache.list.size()+"<br>"); p`Tl)[*
CountControl c=new CountControl(); 6Fk[wH7
c.run(); BT;1"l<
out.print(CountCache.list.size()+"<br>"); '43U v
%>