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: `d^Q!QxE
;N(L,
CountBean.java =+UtAf<n
`"}).{N]C
/* uY(8KW
* CountData.java @87Y/_l
* W!R0:-
* Created on 2007年1月1日, 下午4:44 :<bhQY
* |O6/p7+.
* To change this template, choose Tools | Options and locate the template under M)!"R [V
* the Source Creation and Management node. Right-click the template and choose $./aKJ1B
* Open. You can then make changes to the template in the Source Editor. 9r+'DX?>
*/ Ww60-d}}Q
kX+9U"`
C
package com.tot.count; :*&c'
`"[qb ?z
/** `A%WCd60Tc
* tc[z/
* @author =Gu&0f
*/ u8.Tu7~
public class CountBean { .)$MZyo
private String countType; dt@c,McN|Q
int countId; zCQP9oK!
/** Creates a new instance of CountData */ T*SLM"x
public CountBean() {} 54Rp0otv
public void setCountType(String countTypes){ |&{S ~^$
this.countType=countTypes; M49l2x=]9
} :N _]*>
public void setCountId(int countIds){ _tX=xAO9
this.countId=countIds; Y2XxfZj
} ~-6_-Y|
public String getCountType(){ Y%kOq`uT=n
return countType; ?T_MP"
} g)^s+Y
public int getCountId(){ De^:9<{jc
return countId; [520!JhZY
} \eNB L[
} ~
z3J4s
>W8"Ar
CountCache.java 1P[x.t#
8U(o@1PT
/* >V?0#f45@
* CountCache.java h'};spv
* RqGX(Iuv
* Created on 2007年1月1日, 下午5:01 ?RS:I%bL
* te2vv]W1
* To change this template, choose Tools | Options and locate the template under ^Z#G_%\Y:
* the Source Creation and Management node. Right-click the template and choose +|d]\WlJ
* Open. You can then make changes to the template in the Source Editor. [.fh2XrVM
*/ qe#5;#
GJZjQH-#P
package com.tot.count; #+l`tj4b/
import java.util.*; ZSK_Lux>
/** c'tQA
* (m,H 5
* @author [
5}Q
*/ Nj3iZD|
public class CountCache { u%e~a]
public static LinkedList list=new LinkedList(); Pb>/b\&JS
/** Creates a new instance of CountCache */ YLQ0UeDN'
public CountCache() {} 6];3h>c]N
public static void add(CountBean cb){ KS93v9|
if(cb!=null){ .!KsF
h,pK
list.add(cb); {Ba&
} YwET.(oo
} H}5WglV.
} s$>n U
<^Vj1s
CountControl.java F/BR#J1
'7el`Ff
/* $'3xl2T
* CountThread.java GW;%~qH[,
* lTqlQ<`V
* Created on 2007年1月1日, 下午4:57 DbH;DcV7
* eIalcBY
* To change this template, choose Tools | Options and locate the template under [Cv./hEQi
* the Source Creation and Management node. Right-click the template and choose uOLShNo
* Open. You can then make changes to the template in the Source Editor. I:iMRvp
*/ N4C7I1ihq
; $80}TY '
package com.tot.count; a24 AmoWx
import tot.db.DBUtils; )S%t)}
import java.sql.*; iBAP,cR?`
/** 2=NaqHt(
* )
yMrET
m
* @author :gU5C Um
*/ ap}p?r
public class CountControl{ nS%jnp#
private static long lastExecuteTime=0;//上次更新时间 2L 1,;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 k*fU:q1
/** Creates a new instance of CountThread */ !`I@Rk]`c
public CountControl() {} &N/t%q
public synchronized void executeUpdate(){ ?=M?v;8
Connection conn=null; 9% T"W
PreparedStatement ps=null; i^%$ydg
try{ ?$109wZ:9
conn = DBUtils.getConnection(); N5=BjXSAg
conn.setAutoCommit(false); rnj$u-8
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); u3+B/ 5x
for(int i=0;i<CountCache.list.size();i++){ tj@(0}pi4
CountBean cb=(CountBean)CountCache.list.getFirst(); R*D<M3
CountCache.list.removeFirst(); }l7+W4~
ps.setInt(1, cb.getCountId()); &}k7iaO
ps.executeUpdate();⑴ &R<aRE:+R
//ps.addBatch();⑵
PtbaC6"\
} X n!mdR
//int [] counts = ps.executeBatch();⑶ )/::i
O&$:
conn.commit(); j
%gd:-tA
}catch(Exception e){ +_i{4Iz~p
e.printStackTrace(); +n;nvf}(
} finally{ dn-
[Gnde
try{ f<@!{y2Xe
if(ps!=null) { 2r!ltG3}
ps.clearParameters(); Om0$6O
ps.close(); E@ U]k$M
ps=null; bJ!\eI%ld
} JyMk @Y
}catch(SQLException e){} EYq?NL='
DBUtils.closeConnection(conn); [UzD3VPg
} <@-O06
} 8O,\8:I#
public long getLast(){ Yao}Xo9}
return lastExecuteTime; ):! =XhQ
} R}Lk$#S#
public void run(){ Dd5
9xNKm
long now = System.currentTimeMillis(); XJ4f;U
if ((now - lastExecuteTime) > executeSep) { NVv
<vu
//System.out.print("lastExecuteTime:"+lastExecuteTime); YK3>M"58
//System.out.print(" now:"+now+"\n"); wI_@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); QE(.w
dHP
lastExecuteTime=now; mgjJNzclL
executeUpdate(); b]4dmc*N+
} MJ)lZ!KZ
else{ #4'wF4DR@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); vAUt~X"
} E?XaU~cpc
} 2@zduL'do_
} Sf, z
//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 pD$4nH4KST
':wf%_Iw
类写好了,下面是在JSP中如下调用。 c
3QgX4vq
VyxYv-$Y
<% ~:z.Xu5m
CountBean cb=new CountBean(); Pq omi!1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); p,fV .5q
CountCache.add(cb); =*,SD
out.print(CountCache.list.size()+"<br>"); Q4"\k.
?
CountControl c=new CountControl(); n(F!t,S1i
c.run(); r.H`3m.0q
out.print(CountCache.list.size()+"<br>"); )r9 9zdUk
%>