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: r@G*Fx8Z
i_qY=*a?y
CountBean.java R%r
bysP
Tigw+2
/* 6St=r)_
* CountData.java |Xt G9A>
* xAmtm"
* Created on 2007年1月1日, 下午4:44 S^O9}<2g
* YQ0#j'}/
* To change this template, choose Tools | Options and locate the template under ^[<BMk
* the Source Creation and Management node. Right-click the template and choose Pnytox
* Open. You can then make changes to the template in the Source Editor. ^eW<-n@^
*/ y)kxR
y-<.l=6A
package com.tot.count; Nd8>p.iqO
CKAd\L
/** {}$9
70y
* -CPtYG[s
* @author _p$/.~Xo9
*/ \o<ucp\J
public class CountBean { 3,PR6a,b'
private String countType; -^&=I3bp
int countId; hSehJjEoM
/** Creates a new instance of CountData */ :{u`qi
public CountBean() {} 7q0_lEh
public void setCountType(String countTypes){ dT|XcVKg
this.countType=countTypes; =<]`'15"V
} J 8i;E4R
public void setCountId(int countIds){ vQWmHv\P
this.countId=countIds; i)#-VOhX)
} vh,(]t
public String getCountType(){ 2 6#p,P
return countType; y3~=8!Tj?Q
} b6k`R4S3
public int getCountId(){ o78u>O y
return countId; N'{[BA(eE
} tYA@J[" ^
} }`R,C~-|^
PMjNc_))
CountCache.java ]4aPn
s`yzeo
/* %
/:1eE`!S
* CountCache.java -K|1w'E
* ly[yn{
* Created on 2007年1月1日, 下午5:01 r]9-~1T
* }M4dze
* To change this template, choose Tools | Options and locate the template under vF\>;pcT
* the Source Creation and Management node. Right-click the template and choose RELNWr
* Open. You can then make changes to the template in the Source Editor. >u=
*/ e=;A3S
Wf
c/?{
package com.tot.count; V?XQjH1X
import java.util.*; =O}I{dNKZV
/** }s,NM%oI
* Es>' N3A
z
* @author 8D.c."q
*/ ]B>76?2W
public class CountCache { A f'&, 1=q
public static LinkedList list=new LinkedList(); ~5
6&!4
/** Creates a new instance of CountCache */ )>@S8v,(
public CountCache() {} ]_C"A
public static void add(CountBean cb){ Pe`mZCd^
if(cb!=null){ ?%3dgQB'
list.add(cb); ; Z:[LJd
} 8Lgt
} fcq8aW/z_
} HK)m^!=
I\*6
>
CountControl.java %ap(=^|5
SkuR~!
/* 4t*%(
* CountThread.java L<FXtBJ
* E{
/,
b)
* Created on 2007年1月1日, 下午4:57 /LFuf`bXV
* |WB-N g
* To change this template, choose Tools | Options and locate the template under ixA.b#!1
* the Source Creation and Management node. Right-click the template and choose kk
fWiPO^
* Open. You can then make changes to the template in the Source Editor. 'TeH(?3G
*/ n/KO{:
W.3b]zcV
package com.tot.count; x-i1:W9;
import tot.db.DBUtils; [8T{=+k
import java.sql.*; Y`~B> J
/** cWW?@_
* 8 a]'G)(ts
* @author sVx}(J
*/ "_/ih1z]
public class CountControl{ HH*y$
private static long lastExecuteTime=0;//上次更新时间 fd[N]I3
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )tG. 9"<
/** Creates a new instance of CountThread */ Q`F1t
public CountControl() {} jPSVVOG
public synchronized void executeUpdate(){ \2@J^O1,
Connection conn=null; .wNXvnWr
PreparedStatement ps=null; [IAUJ09>I
try{ `cp\UH@
conn = DBUtils.getConnection(); ?R]`M_^&u!
conn.setAutoCommit(false); 9a*#r;R
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^kfqw0!
for(int i=0;i<CountCache.list.size();i++){ :k\#=u(
CountBean cb=(CountBean)CountCache.list.getFirst(); ULiRuN0 6
CountCache.list.removeFirst(); K]|Ud No
ps.setInt(1, cb.getCountId()); oU|G74e6
ps.executeUpdate();⑴ V'9.l6l
//ps.addBatch();⑵ 4Y(@
KUb
} WEwa<%Ss
//int [] counts = ps.executeBatch();⑶ &tH?m;V
conn.commit(); +/[M
Ex=
}catch(Exception e){ Qvp"gut)%X
e.printStackTrace(); s4bV0k
} finally{ ` <1Wf
try{ ?tYZ/
if(ps!=null) { .D@J\<,+l
ps.clearParameters(); q-! H7o
ps.close(); >'4A[$$4mM
ps=null; NQ`D"n
} r
w!jmvHE&
}catch(SQLException e){} 8 m"k3:e^
DBUtils.closeConnection(conn); 9gg{i6
} 8>YF}\D V
} W6<oy
public long getLast(){ F! !HwI
return lastExecuteTime; >!Yuef
<P
} +vkmS
public void run(){ l!*_[r
long now = System.currentTimeMillis(); +gd5&
if ((now - lastExecuteTime) > executeSep) { t"$~o:U&)
//System.out.print("lastExecuteTime:"+lastExecuteTime); b`X''6
//System.out.print(" now:"+now+"\n"); m(8Tup|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); z>W:+W"o
lastExecuteTime=now; %>FtA)
executeUpdate(); IV,4BQ$
} G(t:s5:
else{ 6qT@M0)i
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); N,TV?Q5l7
} @jn&Wf?
} Gd!-fqNa'x
} ?Ek)" l
//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 D[+LU(
hC2Fup1 @
类写好了,下面是在JSP中如下调用。 `n$Ak5f
Z1 Nep!
<% u ON(LavB
CountBean cb=new CountBean(); :7K
a4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Et3]n$
CountCache.add(cb); /x49!8
out.print(CountCache.list.size()+"<br>"); 0j@mzd2
CountControl c=new CountControl(); ;MN$.x+
c.run(); 7Bj,{9^aJ
out.print(CountCache.list.size()+"<br>"); MhN;GMH
%>