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: 8 f~M6
Xk/:a}-l
CountBean.java j:48l[;ed
r_rdd}=b'
/* )g-0b@z!n
* CountData.java F2n4#b
* t >64^nS
* Created on 2007年1月1日, 下午4:44 .[:WMCc\
* *r~6R
* To change this template, choose Tools | Options and locate the template under "Rf|o6!d
* the Source Creation and Management node. Right-click the template and choose -4J.YF>
* Open. You can then make changes to the template in the Source Editor. u1z!OofN>
*/ i3(5
'
JAwEu79sh
package com.tot.count; `i~J0#P
Csgby(D*O
/** &=Y%4vq
* 5Tidb$L;Du
* @author cqb6]
*/ hJ4 A5m.
public class CountBean { u!VrMH
private String countType; r24
s_
int countId; ^#w9!I{4.
/** Creates a new instance of CountData */ JV2[jo}0N
public CountBean() {} PI*Z>VE?
public void setCountType(String countTypes){ s9u7zqCF
this.countType=countTypes; (r<F@)J
} & )-fC
public void setCountId(int countIds){ C}o^p"M*B3
this.countId=countIds; *li5/=UC5*
} +&1#ob"6lq
public String getCountType(){
hJ8B&u(
return countType; .b2%n;_>.
} 'Ze&
LQ
public int getCountId(){ ~dsx|G?p
return countId; [H`5mY@
} -HFyNk]>
} fB4zqMSfE
94rx4"AN8;
CountCache.java N45@)s!F9j
BSEP*#s
/* Bq,Pk5b
* CountCache.java 3[kl` *`
* ZGd7e.u=
* Created on 2007年1月1日, 下午5:01 ; ?,'jI*1
* rO,n~|YJ
* To change this template, choose Tools | Options and locate the template under ]7|qhAh<L
* the Source Creation and Management node. Right-click the template and choose X5Y. o&
* Open. You can then make changes to the template in the Source Editor. b%j4W)Z
*/ _z"\3hZ
Z= pvoTY
package com.tot.count; 6k1_dRu
import java.util.*; $yFR{_]
/** > 3l3
* (Y?}'?
* @author w/fiNY5FZ
*/ /'>ck2drjk
public class CountCache { U}-hV@y
public static LinkedList list=new LinkedList(); s*>B"#En
/** Creates a new instance of CountCache */ DK%@[D
public CountCache() {} DeN$YE#*
public static void add(CountBean cb){ -K5u5l}
if(cb!=null){ DCCij N
list.add(cb); s*kSl:T@O
} +ldgT"
} 3"6-X_
} R
<u\
-
A6Wtzt2i
CountControl.java 4?x$O{D5?{
p1\EC#Q
/* <2w41QZX
* CountThread.java |e&hm
~R1
* Hn?v/3
* Created on 2007年1月1日, 下午4:57 Hg[AulNna
* ~</H>Jd
* To change this template, choose Tools | Options and locate the template under W TC/mcS
* the Source Creation and Management node. Right-click the template and choose oJ0
#U
* Open. You can then make changes to the template in the Source Editor. w 1O)
*/ t(- 5l
pH?"@
package com.tot.count; vqwSOh|P9
import tot.db.DBUtils; #X<s_.7DJ
import java.sql.*; `]l[p+DO
/** {/qq*0wa
* cvnRd.&
* @author ^0"[l {
*/ OFw93UJ Y
public class CountControl{ s|Zv>Qt
private static long lastExecuteTime=0;//上次更新时间 Rd+`b
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >!P !F(
/** Creates a new instance of CountThread */
] 2lhJ
public CountControl() {} @p7*JLO
public synchronized void executeUpdate(){ y]%Io]!d
Connection conn=null; !*B1Eo--cN
PreparedStatement ps=null; M7AUY#)
try{ !r_2b! dy
conn = DBUtils.getConnection(); t. kOR<
conn.setAutoCommit(false); myWa>Mvb
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); OQsF$%*
for(int i=0;i<CountCache.list.size();i++){ >Co5_sCe
CountBean cb=(CountBean)CountCache.list.getFirst(); GEfTs[
CountCache.list.removeFirst(); WcE/,<^*
ps.setInt(1, cb.getCountId()); N1z:9=(I
ps.executeUpdate();⑴ =a./HCF
//ps.addBatch();⑵ 'Y-Y
By :
} ^WIGd"^
//int [] counts = ps.executeBatch();⑶ B#x.4~YX
conn.commit(); @RI\CqFHR
}catch(Exception e){ RD'i(szi?
e.printStackTrace(); O8w|!$Q.
} finally{ G9a6 $K)b
try{ {rZ )!
if(ps!=null) { JXF@b-c
ps.clearParameters(); ^eWD4Vp|4
ps.close(); K<ok1g'0
ps=null; \@:mq]Y
} \MFjb IL
}catch(SQLException e){} 1mz72K
DBUtils.closeConnection(conn); !5[5l!{x
} 2z027P-Q
} x]jJ
public long getLast(){ X/`M'8v.%
return lastExecuteTime; nfjwWDH
} ;_=+h,n
public void run(){ G8!* &vR/
long now = System.currentTimeMillis(); \TXCq@
if ((now - lastExecuteTime) > executeSep) { %u02KmV.
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5Qgh\4
//System.out.print(" now:"+now+"\n"); =LMM]'no,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .Zv uhOn^
lastExecuteTime=now; Q96^rjY
executeUpdate(); qEV>$>}
} VTvNn
else{ a/H|/CB3
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); rnTjw
"%
} $y+Bril5W
} o@tc
} X=i",5;
//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 ]Br6!U4~
DS1_hbk
类写好了,下面是在JSP中如下调用。 nf9NJ_8}4H
16R0#Q/{+*
<% l|&DI]gw
CountBean cb=new CountBean(); 0P_3%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); use`
y^c
CountCache.add(cb); ptEChoZ6
out.print(CountCache.list.size()+"<br>"); #Vi:-zyY
CountControl c=new CountControl(); Y|96K2BR
c.run(); Z`Sbq{Kx
out.print(CountCache.list.size()+"<br>"); L4-v'Z;
%>