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: GB-=DC6
Eb.{M
CountBean.java MG~^>
I{E10;
/* y]Y)?])
* CountData.java W?$
ImW
* y]/{W}D
* Created on 2007年1月1日, 下午4:44 9+L!
A
* Q/< $ (Y
* To change this template, choose Tools | Options and locate the template under )P$
IXA\
* the Source Creation and Management node. Right-click the template and choose Nk7Q
* Open. You can then make changes to the template in the Source Editor. !u^(<.xJ
*/ k8h$#@^
OvFZ&S[
package com.tot.count; O6`@'N>6P
X 6>Pq
/** <_NF
* )wKuumet
* @author TPkm~>zD.
*/ xT@\FwPr
public class CountBean { nI6`/
private String countType; ^,?]]=mE
int countId; XpM#0hm
/** Creates a new instance of CountData */ `+<5QtD
public CountBean() {} Bdq/Ohw|!
public void setCountType(String countTypes){ 7_JK2
this.countType=countTypes; )q#b^( v
} %1#5
7-
public void setCountId(int countIds){ W
nVX)o
this.countId=countIds; )]/!:I4e
} ~oOOCB
public String getCountType(){ TfJB;
return countType; c=ZX7U
} E;h#3
B9
public int getCountId(){ Q.!8q3`
return countId; N &=,)d~M
} 1{DHlyA6g
} ^7(zoUn:
aeSXHd?+(
CountCache.java FO*Py)/rX
Nf3L
/* 0BD3~Lv
* CountCache.java ed&,
* MJK L4 G
* Created on 2007年1月1日, 下午5:01 dL v\H&
* ecr pv+
* To change this template, choose Tools | Options and locate the template under T9u/|OP
* the Source Creation and Management node. Right-click the template and choose u{I)C0
* Open. You can then make changes to the template in the Source Editor. x5{ zGv.j
*/ Yh4e\]ql~N
L!5%;!>.P
package com.tot.count; n2$*Z6.G
import java.util.*; *F&C`]
/** e\/Lcng
* 6tP^_9njy
* @author rNZN}g
*/ J7S
public class CountCache { +f|u5c
public static LinkedList list=new LinkedList(); XO\P4x:c
/** Creates a new instance of CountCache */ +HNQ2YZ
public CountCache() {} 4j/8Otn
public static void add(CountBean cb){ [Q)lJTs
if(cb!=null){ Byon2| nf7
list.add(cb); MvObx'+
} ! k&<
} QarA.Ne~
} RM,r0Kv17Y
3pm;?6i6
CountControl.java " >;},$
#Jg)HU9
/* A`IE8@&Z'
* CountThread.java 2TY|)ltsF
* K47W7zR
* Created on 2007年1月1日, 下午4:57 j5tA!o
* 5&6S["lt
* To change this template, choose Tools | Options and locate the template under l 4(-yWC$H
* the Source Creation and Management node. Right-click the template and choose #Ey!?Z
* Open. You can then make changes to the template in the Source Editor. 7j{SCE;
*/ Dk8"
H>*
.|cQ0:B[
package com.tot.count; N-;e"
g
import tot.db.DBUtils; l9# v r
import java.sql.*; M" %w9)@
/** NO"=\Zn6
* "5]GEzM3O
* @author k_$w+Q
*/ "<NQ2Vr]5
public class CountControl{
5G=2=E
private static long lastExecuteTime=0;//上次更新时间 k.?b2]@$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Q+gQ"l,95
/** Creates a new instance of CountThread */ `AQv\@wp
public CountControl() {} P)ZGNtO9fG
public synchronized void executeUpdate(){ K5'@$Km
Connection conn=null; =p:D_b
PreparedStatement ps=null;
>Xh9{/o
try{ #~ UG9@a
conn = DBUtils.getConnection(); p-r}zc9@
conn.setAutoCommit(false); b4i=eI8
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^#p Su
for(int i=0;i<CountCache.list.size();i++){ &`GQS|
CountBean cb=(CountBean)CountCache.list.getFirst(); _=8x?fC:rl
CountCache.list.removeFirst(); sZ7{_}B
ps.setInt(1, cb.getCountId()); EnZrnoGM
ps.executeUpdate();⑴ wSnY;Z9W_
//ps.addBatch();⑵ @~xNax&^
} 4)i/B99k
//int [] counts = ps.executeBatch();⑶ (?D47^F &
conn.commit(); b$H{|[
}catch(Exception e){ u\.7#D>
e.printStackTrace(); K6{{\r
} finally{ WTZP}p1
try{ j;)U5X
if(ps!=null) { %jim] ]<S[
ps.clearParameters(); Fz~-m# Ts
ps.close(); R"VmN2
ps=null; _6(QbY'JV`
} SX$v&L<
}catch(SQLException e){} +QqYf1@F
DBUtils.closeConnection(conn); p.n+m[
} A9!%H6
} 7;+:J;xf66
public long getLast(){ a3sXl+$D@
return lastExecuteTime; a>G|t5w
} 6m|j "m
public void run(){ Ft#d&
I
long now = System.currentTimeMillis(); [0w@0?[
if ((now - lastExecuteTime) > executeSep) { `c ^2
//System.out.print("lastExecuteTime:"+lastExecuteTime); }L3k pw
//System.out.print(" now:"+now+"\n"); b<~\IPY
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); f^Lw3|rq4
lastExecuteTime=now; b7p&EK"Hm
executeUpdate(); z;x$tO
} ]]J2#mN:n
else{ ehPrxIyC
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); EQET:a:g
} JFIUD{>fp
} XL1v&'HLV
} E?m(&O
j
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 5\A[ra
{Ug?k<h7|
类写好了,下面是在JSP中如下调用。 ^duNEu0*
_jQ"_Ff
<% 4jfkCU
CountBean cb=new CountBean(); m$Lq#R={Z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }1f@>'o
CountCache.add(cb); m(L]R(t
out.print(CountCache.list.size()+"<br>"); LkD$\i
CountControl c=new CountControl(); OEnJ".&V
c.run();
7aj|-gZ
out.print(CountCache.list.size()+"<br>"); M1^,g~e
%>