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: X(nyTR8
qVE0[ve
CountBean.java #T^2=7 w
c!4F0(n4
/* AT~,
* CountData.java E3wL n/<
* M }d:B)cz
* Created on 2007年1月1日, 下午4:44 Q]xkDr?
* \BXzmok
* To change this template, choose Tools | Options and locate the template under +C{-s
* the Source Creation and Management node. Right-click the template and choose mSxn7LG
* Open. You can then make changes to the template in the Source Editor. HN{c)DIm]
*/ ~dRstH7u
e;6KxvX~
package com.tot.count; SE]5cJ'>
4F~^RR"
/** EaO@I.[
* DdgiY9a.
* @author V >'
*/ #lLUBJ#:
public class CountBean { ]zSFX
=~(S
private String countType; g8%O^)d=>
int countId; &P|[YP37_
/** Creates a new instance of CountData */ -o6rY9\_!
public CountBean() {} :BF ? r
public void setCountType(String countTypes){
[fa4
this.countType=countTypes; 'cXdc
} UUJQc~=
public void setCountId(int countIds){ !=,4tg`
this.countId=countIds; `NsjtT'_
} sV
public String getCountType(){ i
U$~H
return countType; tUJRNEg
} uPA
(1
public int getCountId(){ (G>[A}-
return countId; ;[sW\Ou
} { :tO
RF
} J/?Nf2L4
// o.+?S
CountCache.java "n!yK
;"wCBuXcu
/* tF0jH+7J-
* CountCache.java B ;1qy[
* +tqErh?Al
* Created on 2007年1月1日, 下午5:01 85GIEUvH/
* %T{]l;5
* To change this template, choose Tools | Options and locate the template under }Q/onBt
* the Source Creation and Management node. Right-click the template and choose AC)
M2;
* Open. You can then make changes to the template in the Source Editor. jV3PTU
*/ 7Gc{&hp*
\c}(rqT
package com.tot.count; dw
bR,K
import java.util.*; 5~JT*Ny
/** H$(bSw$
* ;<AcW.jx
* @author EiW|+@1
*/ /fr> Fd
public class CountCache { u]J@65~'b
public static LinkedList list=new LinkedList(); 6Dq4Q|C
/** Creates a new instance of CountCache */ #.bW9j/
public CountCache() {} T
pkSY`T
public static void add(CountBean cb){ qos7u91z
if(cb!=null){ u*l|MIi6J
list.add(cb); p~qe/
} Z'JS@dV
} hArY$T&MB
} TC\+>LXiZ
!+T1kMP+l
CountControl.java ?['!0PF
5AYOM=O]t
/* %a;#]d
* CountThread.java RdTM5ANT
* =Ph8&l7~sp
* Created on 2007年1月1日, 下午4:57 ut{T:kT
* j9+$hu#a
* To change this template, choose Tools | Options and locate the template under _!\d?]Ya
* the Source Creation and Management node. Right-click the template and choose +2~kHrv
* Open. You can then make changes to the template in the Source Editor. ,kN;d}bg
*/ e#(Ck{e
ETe4I`d{
package com.tot.count; !_<6}:ZB
import tot.db.DBUtils; ff"wg\O4
import java.sql.*; d8j1L/e
/** jVj5 ; }
* ]A#lV$
* @author ^:eZpQ [,
*/ ;;Q^/rkC
public class CountControl{ K7+yU3
private static long lastExecuteTime=0;//上次更新时间 WSkGVQu
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 h+ f>#O+:
/** Creates a new instance of CountThread */ 0B
NLTRv
public CountControl() {} xt{'Be&Ya+
public synchronized void executeUpdate(){ H",B[
YK
Connection conn=null; _'u]{X\k{J
PreparedStatement ps=null; EdJL&*
try{ bLgH3[{
conn = DBUtils.getConnection(); /:&!o2&1H
conn.setAutoCommit(false); l>?c AB[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^PksXfk
for(int i=0;i<CountCache.list.size();i++){ J3K=z
CountBean cb=(CountBean)CountCache.list.getFirst(); RgE`H r
CountCache.list.removeFirst(); "/#JC}]
ps.setInt(1, cb.getCountId()); tT$OnZu&
ps.executeUpdate();⑴ *sho/[~_
//ps.addBatch();⑵ ^URCnJ67Se
} mP(3[a_Q
//int [] counts = ps.executeBatch();⑶ (C2 XFg_
conn.commit(); Nk`UQ~g$
}catch(Exception e){ BT$p~XB
e.printStackTrace(); n/H
OP
} finally{ \{,TpK.
try{ @=Kq99=\U
if(ps!=null) { R$awg SE
ps.clearParameters(); IP~!E_e}\
ps.close(); ^4y]7p
ps=null; =8kmFXo
} ])x1MmRg\
}catch(SQLException e){} 092t6D}
DBUtils.closeConnection(conn); R$a<=
} \INH[X#>
} !QUY (
public long getLast(){ j=_rUc'Me
return lastExecuteTime; Q M,!-~t
} &K)8
public void run(){ weitDr6
long now = System.currentTimeMillis(); )Nv1_en<!
if ((now - lastExecuteTime) > executeSep) { bQAznd0
//System.out.print("lastExecuteTime:"+lastExecuteTime); KaGUpHw
//System.out.print(" now:"+now+"\n"); &c`-/8c
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dj|5'<l2
lastExecuteTime=now; ]|;+2@kDR
executeUpdate(); Tt[zSlIMx
} BG{f)2F\
else{ 'm%{Rz>j
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2EY"[xK|
} ?HZp@&
} .=_p6_G
} cpY{o^
//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 Hh<H~s [
~,'{\jDrS
类写好了,下面是在JSP中如下调用。 SGd]o"VF
ZSMed(//b
<% <Ox[![SR
CountBean cb=new CountBean(); <3YZ0f f>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ]`E+HLEQ'
CountCache.add(cb); ,!ZuH?Z
out.print(CountCache.list.size()+"<br>"); D-3[#~MV
CountControl c=new CountControl(); |Td+,>,
c.run(); 4DXbeQs:
out.print(CountCache.list.size()+"<br>"); ajbe7#}
%>