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: `e?;vA&
} }f_
CountBean.java 2#b<d?"
a#Kmj0
/* $35,\ZO>
* CountData.java }*.:Hv"
* 1]>$5 1Q
* Created on 2007年1月1日, 下午4:44 nGx ~)T
* L7Qo-
* To change this template, choose Tools | Options and locate the template under 7~ *;=,mw
* the Source Creation and Management node. Right-click the template and choose B 9LSxB
* Open. You can then make changes to the template in the Source Editor. D(qHf9
*/ i'!jx.
t}]9VD9
package com.tot.count; "J P{Q
L2CW'Hd
/** QJ a4R
* JlC<MQ?
* @author N
b3I%r
*/ MUbhEau?
public class CountBean { 5ys#L&q'Z
private String countType; ;23=p=/h
int countId; +R
"AA_A?
/** Creates a new instance of CountData */ U_x0KIm
public CountBean() {} k40Ep(M}
public void setCountType(String countTypes){ rDIhpT)a
this.countType=countTypes; M'cJ)-G
} w~<FG4@LU
public void setCountId(int countIds){ ;JOD!|
this.countId=countIds; YO@hE>
} jOBY&W0r
public String getCountType(){ :
cFF
return countType; gf0PMc3l
} qs!>tw
public int getCountId(){ _&W0e} 4
return countId; h`?y2?O
} 4@DVc7\x$
} i^je.,Bi
tgO+*q5B
CountCache.java 4-y6MH
4JGE2ArR
/* R]CZw;zS_
* CountCache.java Ab*]dn`z
* "w*@R8v
* Created on 2007年1月1日, 下午5:01 so} l#
* ;e&!
* To change this template, choose Tools | Options and locate the template under wX-RQ[2X
* the Source Creation and Management node. Right-click the template and choose {V[Ha~b%*
* Open. You can then make changes to the template in the Source Editor. ;US83%*
*/ 5\VxXiy0
4$%`Qh>yA
package com.tot.count; yrO?Np
import java.util.*; Jf_]Z
/** +yth_9
* Ru)(dvk}S
* @author BwJNi6,
*/ IK8%Q(.c
public class CountCache { L<0=giE
public static LinkedList list=new LinkedList(); xC)7eQn/R
/** Creates a new instance of CountCache */ 4w@v#H@
public CountCache() {} 6yN"
l
Q7
public static void add(CountBean cb){ %h0D)6j
if(cb!=null){ --Oprl
list.add(cb); c+1vqbqHG
} /M 0 p_4
} u/} xE7G
} PM@XtL7J
j\!
e9M
CountControl.java @|^jq
Z%Vr+)!4
/* DX|uHbGg
* CountThread.java pw!@Q?R
* B9wp*:.
* Created on 2007年1月1日, 下午4:57 #De(*&y2
* JdtPY~k0
* To change this template, choose Tools | Options and locate the template under 77``8,
* the Source Creation and Management node. Right-click the template and choose .
/Y&\<
* Open. You can then make changes to the template in the Source Editor. 60'6/3
*/ -=}b;Kf-
7O:"~L
package com.tot.count; :H{Bb{B%
import tot.db.DBUtils; ~+<<bzY
import java.sql.*; g+.0c=G(
/** [qiOd!
* &uPDZ#C-
* @author }0Y`|H\v
*/ Hv3W{|
public class CountControl{ (e(Rr4
private static long lastExecuteTime=0;//上次更新时间 )R~a;?T_c0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 2@fa
rx:
/** Creates a new instance of CountThread */ +1x)z~q=
public CountControl() {} zFOL(s.h|0
public synchronized void executeUpdate(){ !Pw$48cg
Connection conn=null; q=njKC
PreparedStatement ps=null; ;:U<ce=
try{ O'OFz}x),
conn = DBUtils.getConnection(); A9t8`|1"%H
conn.setAutoCommit(false); /0
_zXQyV
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (oF-O{
for(int i=0;i<CountCache.list.size();i++){ oQ{cSThj
CountBean cb=(CountBean)CountCache.list.getFirst(); =C#*!N73
CountCache.list.removeFirst(); G&jZ\IV
ps.setInt(1, cb.getCountId()); a/34WFC
ps.executeUpdate();⑴ Jns/v6
//ps.addBatch();⑵ ]Ym=+lgi
} %0lf
//int [] counts = ps.executeBatch();⑶ VxkEe z'|
conn.commit(); `&H04x"Y$>
}catch(Exception e){ 5E`JD
e.printStackTrace(); >d97l&W
} finally{ J)#S-ZB+'k
try{ ac|/Y$\w
if(ps!=null) { .wD>Gs{sH[
ps.clearParameters(); )L >Q;'
ps.close(); e9lOk)`t
ps=null; %;tJQ%6-.S
} w]F!2b!
}catch(SQLException e){} \TZ|S,FS
DBUtils.closeConnection(conn); bH,M,xIL2
} -8/ JP
} rfc|`*m}0
public long getLast(){
k1RV'
return lastExecuteTime; /eb-'m
} !O 8.#+
public void run(){ IhfZLE.,
long now = System.currentTimeMillis(); cN5"i0xk
if ((now - lastExecuteTime) > executeSep) { wh*:\_!0\
//System.out.print("lastExecuteTime:"+lastExecuteTime); ZL,6_L/
//System.out.print(" now:"+now+"\n"); t| _{;!^
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); FD))'!>
lastExecuteTime=now;
jC4O`
executeUpdate(); o<nS_x
} &1l~&,,
else{ *t]v}ZV*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); jI A#!4
} }qL~KA{&
} >;7a1+`3
} ]q&tQJ/Fa
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ??j&i6sp
k/@Tr
:
类写好了,下面是在JSP中如下调用。 NZP7r;u
=-5[Hn%
<% @i{]4rk lv
CountBean cb=new CountBean(); KJX>DL 9\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \f<z*!,D$
CountCache.add(cb); &Q~)]|t
out.print(CountCache.list.size()+"<br>"); UhdqY]
CountControl c=new CountControl(); :T5A84/C
c.run(); Fo(y7$33*
out.print(CountCache.list.size()+"<br>"); uRpBeH]Z"
%>