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: 58zs%+F
AE!WYE
CountBean.java LinARMPv
IrQ8t!
/* ~-x8@ /
* CountData.java
F7a &-
* yq+<pfaqvK
* Created on 2007年1月1日, 下午4:44 _?<Y>B, E
* 'D%No!+Py
* To change this template, choose Tools | Options and locate the template under !VpZo*+
* the Source Creation and Management node. Right-click the template and choose ^y'xcq
* Open. You can then make changes to the template in the Source Editor. q)gZo[]~
*/ W>
.O"Ri
idnn%iO
package com.tot.count; i,rP/A^q
Y<TlvB)w
/** ONJW*!(
* X@Eq5s
* @author }`6-^lj
*/ VOwt2&mZ
public class CountBean { ?2[=llS4
private String countType; fOiLb.BW
int countId; k/AcXU%O+
/** Creates a new instance of CountData */ AbUU#C7
public CountBean() {} 8OH<ppi
public void setCountType(String countTypes){ ASY
uZ
this.countType=countTypes; KIn^,d0H
} eHK}U+"\
public void setCountId(int countIds){ FW#Lf]FJ
this.countId=countIds; -aG( Yx
}
/ :"%m:-P
public String getCountType(){ Ek_k_!
return countType; X
+;Q=
} Noz+\O\
public int getCountId(){ Iu|G*~\
return countId; a<tUpI$
} OdgfvHDgW
} p9R`hgx
CvmZW$5Yo
CountCache.java D}"\nCz}y&
j)Kk:BFFY
/* a1ZGMQq!
* CountCache.java G39H@@ *O0
* QnZR
* Created on 2007年1月1日, 下午5:01 ( f8g}2
* deaxb8'7
* To change this template, choose Tools | Options and locate the template under ({D.oS
* the Source Creation and Management node. Right-click the template and choose .6!]RA5!=
* Open. You can then make changes to the template in the Source Editor. J&^r}6D
*/ 1w+OnJI?
FePJ8
package com.tot.count; ,iCd6M{
import java.util.*; 8"wA8l.
/** "A__z|sQ
* z QoMHFL3
* @author +;#hED;8
*/ .
)Fn]x"<
public class CountCache { H:U1#bQQ:
public static LinkedList list=new LinkedList(); ;G!X?(%+
/** Creates a new instance of CountCache */ meR%);\
public CountCache() {} v|_?qBs"
public static void add(CountBean cb){ l,h#RTfry
if(cb!=null){ I OF~V)8k=
list.add(cb); v0X5`VV
} '\1%%F7
} Q9K
Gf;
} R.A}tV=j#
!f)'+_d
CountControl.java r d]HoFE
r!Eo8C
/* ( NjX?^
* CountThread.java {ZbeF#*"
* %P_\7YBC>
* Created on 2007年1月1日, 下午4:57 fouy??
* '7>Vmr6
* To change this template, choose Tools | Options and locate the template under QC4_\V>[
* the Source Creation and Management node. Right-click the template and choose tt|U,o
* Open. You can then make changes to the template in the Source Editor. AEPgQ9#E
*/ |Y(].G,
4TG|
package com.tot.count; dyWWgC%A
import tot.db.DBUtils; ksDG8^9>]
import java.sql.*; "$0f.FO:i
/** \'E _
* a6WE,4T9
* @author 6e |
*/ Aplqxvth
public class CountControl{ RfN5X}&A
private static long lastExecuteTime=0;//上次更新时间 'ZT!a]4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 sf\;|`}
/** Creates a new instance of CountThread */ .%->
public CountControl() {} NXeo&+F
public synchronized void executeUpdate(){ TM!R[-\
Connection conn=null; Vz 5:73
PreparedStatement ps=null; 1b6gTfU
try{ xO1d^{~^^
conn = DBUtils.getConnection(); =AgY8cF!sl
conn.setAutoCommit(false); ,)]ZD H
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \`>Y
for(int i=0;i<CountCache.list.size();i++){ t T-]Vj.
CountBean cb=(CountBean)CountCache.list.getFirst(); 6ap,XFRMh
CountCache.list.removeFirst(); z@~1e]%
ps.setInt(1, cb.getCountId()); <]wN/B-8J
ps.executeUpdate();⑴ }'H Da M
//ps.addBatch();⑵ Q2rZMK
} m
7 Fz&bN
//int [] counts = ps.executeBatch();⑶ )QBsyN<x6
conn.commit(); *tRJ=
}catch(Exception e){ "45BOw&72G
e.printStackTrace(); Tj:+:B(HB
} finally{ 9\Xl3j!
try{ 3M1(an\nW
if(ps!=null) { e1<28g
ps.clearParameters(); "a,Tc2xk
ps.close(); @Zq,mPaR$
ps=null; WR'A%"qBwi
} S^x9 2&!
}catch(SQLException e){} y]?$zbB
DBUtils.closeConnection(conn); "g=ux^+X\
} n1sH`C[c
} `=-}S+
public long getLast(){ $S,Uoh
return lastExecuteTime; 6_XX[.%
} T7W+K7kbI
public void run(){ U4N
S.`V
long now = System.currentTimeMillis(); `M7){
if ((now - lastExecuteTime) > executeSep) { e6F:['j
//System.out.print("lastExecuteTime:"+lastExecuteTime); FswFY7
8
//System.out.print(" now:"+now+"\n"); cz T@ txF
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dk(-yv'
lastExecuteTime=now;
}U^9(
executeUpdate(); [MiD%FfcNH
} ZgXh[UHQy
else{ H}U&=w'
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); %mcuYR'D}
} G^2"\4R]p
} zG@!(
} G&uj}rj
//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 PTePSj1N
*=2jteG=3.
类写好了,下面是在JSP中如下调用。 ZVGw@3
$%t{O[(
<% fi?[ e?|c@
CountBean cb=new CountBean(); O-y"]Wrv
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ?QuFRl,ZJ
CountCache.add(cb); xxV{1, H2
out.print(CountCache.list.size()+"<br>"); +=}%
7o
CountControl c=new CountControl(); e.HN%LrhS
c.run(); <0kRky$
out.print(CountCache.list.size()+"<br>"); (g4g-"rc
%>