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: 6LGy0dWpG
7=YjY)6r^
CountBean.java %;SOe9
@O;gKFx
/* B&l5yI
b
* CountData.java {8NnRnzU
* 4M)
s
* Created on 2007年1月1日, 下午4:44 QLq^[>n
* 8 |2QJ
* To change this template, choose Tools | Options and locate the template under v&[Ff|>
* the Source Creation and Management node. Right-click the template and choose 3SRz14/W_R
* Open. You can then make changes to the template in the Source Editor. B(x$
Ln"y[
*/ F`l r5
UjNe0jt%s
package com.tot.count; V~V_+
gNon*\a,-B
/** .xRJ )9q
* jU1 ([(?"
* @author `0@onDQVc=
*/ s~ZLnEb
public class CountBean { gr\UI!]F
private String countType; 7*bUy)UZ
int countId; &|;XLRHP}
/** Creates a new instance of CountData */ OK{_WTCe>
public CountBean() {} xPFNH`O&
public void setCountType(String countTypes){ OH2Xxr[bQ
this.countType=countTypes; =(ULfz[:
} ]8)nIT^EP
public void setCountId(int countIds){ 5PY,}1`
this.countId=countIds; 0n5{Wr$
} jB+K)NXHL
public String getCountType(){ @dl{.,J
return countType; +RXKI{0Km
} /%E X4
W
public int getCountId(){ s-V5\Lip,
return countId; 89*txYmx
} ~x:\xQti
} Ks|qJ3;
D%L}vugxK
CountCache.java ZPrL)']
lTl-<E;
/* tI2V)i!
* CountCache.java 7 &y'\
* E$B7E@(U
* Created on 2007年1月1日, 下午5:01 [ML%u$-
* T%{qwZc+mJ
* To change this template, choose Tools | Options and locate the template under #bxU I{*J
* the Source Creation and Management node. Right-click the template and choose ElJM.
a
* Open. You can then make changes to the template in the Source Editor. ~p9nAACU
*/ ?P<8Zw
8UH
c,np
package com.tot.count; QU4/hS;Ux
import java.util.*; #G'Y2l
/** qmNg Ez%
* :~K c"Pg
* @author oD_n+95B
*/ T$ <l<.Qd
public class CountCache { )f#raXa5+
public static LinkedList list=new LinkedList(); blbL49;
/** Creates a new instance of CountCache */ [PVem
public CountCache() {} AfU~k!4`
public static void add(CountBean cb){ ^FaBaDcnl
if(cb!=null){ YNEPu:5J
list.add(cb); A~MAaw!YE
} |y,%dFNLf
} j<H5i}
} T(Q(7
`zD]*i(
CountControl.java M4MO)MYJ
8ZmU(m
/* Lye^G%{
* CountThread.java JHF<vyt5<
* !Ee#jCXS
* Created on 2007年1月1日, 下午4:57 *V@>E2@
* _gAU`aO^
* To change this template, choose Tools | Options and locate the template under "
3ryp
A
* the Source Creation and Management node. Right-click the template and choose uVnbOqR<X
* Open. You can then make changes to the template in the Source Editor. X~m*` UH
*/ 1y\-Iz^
~
ZkSYW<
package com.tot.count; PtfxF]%H
import tot.db.DBUtils; [^oTC;
import java.sql.*; xqP DL9\
/** r&$r=f<
* J.nJ@?O+
* @author SSoD}N
*/ o75Hit
public class CountControl{ ]/G~ L
private static long lastExecuteTime=0;//上次更新时间 x~!gGfP
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0A]+9@W;
/** Creates a new instance of CountThread */ =6PTT$,
public CountControl() {} >!o||Yn
public synchronized void executeUpdate(){ :Nry |
Connection conn=null; N*Is_V\R
PreparedStatement ps=null; 7/ $r
try{ F 7v 1rf]
conn = DBUtils.getConnection(); ~"eQPTd
conn.setAutoCommit(false); XsOz
{?G
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); d7g3VF<j
for(int i=0;i<CountCache.list.size();i++){ L?aaR%6#
CountBean cb=(CountBean)CountCache.list.getFirst(); ]@Gw$
CountCache.list.removeFirst(); #0;H'GO?c
ps.setInt(1, cb.getCountId()); ;|C[.0;kgv
ps.executeUpdate();⑴ Sbf+;:D
//ps.addBatch();⑵ hn$l<8=Q_
} -w>2!@8
//int [] counts = ps.executeBatch();⑶ ;M)l7f
conn.commit(); <B+xE?v4
}catch(Exception e){ Z@Tb3N/[
e.printStackTrace(); #2dd`F8
} finally{ etcpto=Mo
try{ BQ[,(T`+R
if(ps!=null) { l_?r#Qc7
ps.clearParameters(); M1>2Q[h7
ps.close(); Mg7nv\6
ps=null; d9@Pze">e
} khXp}p!Zm
}catch(SQLException e){} f( %r)%
DBUtils.closeConnection(conn); ,PmQ}1kGW
} L%hVts'
} GjHV|)^
public long getLast(){ VG)Y$S8.>
return lastExecuteTime; JPsR7f
} 58v q5j<V
public void run(){ '4T]=s~N
long now = System.currentTimeMillis(); cH==OM7&-
if ((now - lastExecuteTime) > executeSep) { I;=HXL
//System.out.print("lastExecuteTime:"+lastExecuteTime); :)djHPP*
//System.out.print(" now:"+now+"\n"); vt(A?$j|A
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); =|Q7k +b
lastExecuteTime=now; t;>"V.F<1
executeUpdate(); Ao2m"ym
} 'N7AVj
else{ *8WcRx
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); JGLjx"Y
} H#Aar
} -5&|"YYjr{
} #3+-vyZm
//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 P7X':
K #f*LV5
类写好了,下面是在JSP中如下调用。 W7sx/O9
b*AL,n?
<% q#=}T~4j
CountBean cb=new CountBean(); }mhD2 ' E
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); J&vmW}&
CountCache.add(cb); A_:YpQ07@
out.print(CountCache.list.size()+"<br>"); [~%\:of70n
CountControl c=new CountControl(); <"&I'9
c.run(); o<pb!]1
out.print(CountCache.list.size()+"<br>"); c@uNA0
p
%>