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: $>UzXhf}\
%FU[j^
CountBean.java }B-A*TI<h
uM}O8N
/* E;4a(o]{t
* CountData.java M<)2
* [jw o D
* Created on 2007年1月1日, 下午4:44 0o]K6b
* #r:`bQ0;
* To change this template, choose Tools | Options and locate the template under 7q 2YsI
* the Source Creation and Management node. Right-click the template and choose J]0#M:w&
* Open. You can then make changes to the template in the Source Editor. %awS*
*/ ^sKXn:)
ASvPr*q/
package com.tot.count; s]iOC6v
.{-yveE
/** O5Lv:qAa
* kTz
* @author M\&~ Dmd
*/
n@Ag`}
public class CountBean { |
#Pc
e
private String countType; DVJc-.x8
int countId; i[pf*W0g
/** Creates a new instance of CountData */ 8j}m\^si
public CountBean() {} LXLDu2/@
public void setCountType(String countTypes){ :RsPGj6
this.countType=countTypes; |^Es6 .~
} b-?o?}*
public void setCountId(int countIds){ d_+8=nh3
this.countId=countIds; =]a@)6y
} p|d9g
^
public String getCountType(){ bJm0
return countType; hD1AK+y
} #P#R~b]
public int getCountId(){ (NdgF+'=
return countId; Ij1]GZ`A(
} j>xVy]v= |
} k~f+L O
iyYY)roB
CountCache.java j/D)UWkR
]$*{<
/* K eI:/2
* CountCache.java o%%x'uC
* J'yN' 0
* Created on 2007年1月1日, 下午5:01 J&:W4\ m
* fVUBCu
* To change this template, choose Tools | Options and locate the template under w3qf7{b
* the Source Creation and Management node. Right-click the template and choose _]UDmn[C
* Open. You can then make changes to the template in the Source Editor. `^L<db^A
*/ $|(|Qzi%
lE)rRG+JLW
package com.tot.count; xH_ie
import java.util.*; I`W-RWZ
/** B"m:<@ "
* }c4E 2c
* @author "42$AaS
*/ o:8S$F`O@
public class CountCache { ,{?bM
public static LinkedList list=new LinkedList(); u rXb!e{l
/** Creates a new instance of CountCache */ kgI=0W>
public CountCache() {} N~5WA3xd
public static void add(CountBean cb){ Mc7 <[a
if(cb!=null){ cm@ oun
list.add(cb); 5u)^FIBj
} `s83rhs`!
} (U'7Fc
} V,XP&,no\j
y-<PsP-I
CountControl.java Z"~6yF
wGzXp5
dl
/* ;%rs{XO9
* CountThread.java /2_B$
* -wtTq
ph'
* Created on 2007年1月1日, 下午4:57 *]:G7SW{
* R5NRCI
* To change this template, choose Tools | Options and locate the template under yToT7 X7F7
* the Source Creation and Management node. Right-click the template and choose ##`;Eh0a
* Open. You can then make changes to the template in the Source Editor. /md Q(Dm
*/ 1FD7~S|
4lY&=_K[)
package com.tot.count; Owh*KY:
import tot.db.DBUtils; PK-}Ldj
import java.sql.*; r\l3_t
/** [I++>4
* lrmt)BLoh
* @author mq{$9@3
*/ } Jdh^t .
public class CountControl{ c<+g|@A#
private static long lastExecuteTime=0;//上次更新时间 hpqHllL
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 m0BG9~p|
/** Creates a new instance of CountThread */ [NCXn>Z
public CountControl() {} :\1rQT
public synchronized void executeUpdate(){ Jm]]>K8.3V
Connection conn=null; u-%r~ }
PreparedStatement ps=null; ++T
"+p
try{ )I Y 5Y
conn = DBUtils.getConnection(); GG@I!2,_
conn.setAutoCommit(false); HC9vc,Fp
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); w
L/p.@
for(int i=0;i<CountCache.list.size();i++){ 0,1L e$)6
CountBean cb=(CountBean)CountCache.list.getFirst(); %S
>xSqX
CountCache.list.removeFirst(); _q$0lqq~u
ps.setInt(1, cb.getCountId()); xP{HjONu
ps.executeUpdate();⑴ i_[
HcgT-
//ps.addBatch();⑵ 3ZW/$KP/
} A=v lC?&Z
//int [] counts = ps.executeBatch();⑶ .\ ;l-U
conn.commit(); Jo7fxWO_g
}catch(Exception e){ 3D?IG\3
e.printStackTrace(); IL+#ynC
} finally{ lQp89*b?=U
try{ zx\.2<K
if(ps!=null) { 7X9+Qj;
ps.clearParameters(); vI
pO/m.3
ps.close(); lgCHGv2@
ps=null; VL_)]LR*)
} k8InbX[
}catch(SQLException e){} dxzvPgi?
DBUtils.closeConnection(conn); wo7N7R5
} 6pM"h5hA
} =Q/w% 8G
public long getLast(){ -,K*~z.l
return lastExecuteTime; ^G|w8t+^
} @K,2mhE~h
public void run(){ O tXw/
long now = System.currentTimeMillis(); ]iz_w`I\
if ((now - lastExecuteTime) > executeSep) { ~I8v5 H
//System.out.print("lastExecuteTime:"+lastExecuteTime); SKB@
//System.out.print(" now:"+now+"\n"); v?Z'[l
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); S`pF7[%rp
lastExecuteTime=now; f0-RhR
executeUpdate(); X0^zw^2W
} SjZd0H0
else{ T$gkq>!j<E
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); J>f
/u:.
} a6;gBoV
} i:l80 GK
} 7^kH8qJ)
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 #rhVzN-?)W
P\D[n-&
类写好了,下面是在JSP中如下调用。 EsT0"{
Nhjle@J<
<% &FL%H;Kfx
CountBean cb=new CountBean(); Z7`5x
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); U3mXm?f
CountCache.add(cb); Eem 2qKj
out.print(CountCache.list.size()+"<br>"); z`\#$
CountControl c=new CountControl(); 5T!&r
c.run(); Nawp t%
out.print(CountCache.list.size()+"<br>"); o&CghF
%>