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: $@FD01h.t3
sDK
lbb
CountBean.java P_j?V"i<
_Hl[Fit<j1
/* Y]{<IF:
* CountData.java v{i'o4
* !(*mcYA*W
* Created on 2007年1月1日, 下午4:44 gq*- v:P>
* zPe4WE|
* To change this template, choose Tools | Options and locate the template under R/waWz\D
* the Source Creation and Management node. Right-click the template and choose %'kaNpBz
* Open. You can then make changes to the template in the Source Editor. v$K`C;
*/ (;$J5
Vg#s
package com.tot.count; ^5qX+!3r{
;
@
h{-@
/** AT<gV/1l
* 00Tm0rY
* @author sD1L
P
*/ _YWw7q
public class CountBean { l\-1W2
private String countType; HLg/=VF7?
int countId; 1Z'cL~9
/** Creates a new instance of CountData */ 9hHQWv7TgK
public CountBean() {} !.zUY6
public void setCountType(String countTypes){ -TU7GCb=
this.countType=countTypes; Nb>|9nu
O
} %:h)8e-;
public void setCountId(int countIds){ w
(W+Y+up
this.countId=countIds; gAhCNOp
} @X>k@M
public String getCountType(){ ^b~&}uU
return countType; Kf76./
} LZMdW
#,[
public int getCountId(){ $)mq
return countId; %.r{+m
} r) T^ Td1
} <GF)5QB
VQZ3&]o
CountCache.java F8 ;M++
TYw0#ZXo
/* (sW:^0 p
* CountCache.java g.kpUs
* k~>9,=::d
* Created on 2007年1月1日, 下午5:01 /R^HRzTO
* !
W$u~z
* To change this template, choose Tools | Options and locate the template under ')5W
* the Source Creation and Management node. Right-click the template and choose Ms<^_\iPN
* Open. You can then make changes to the template in the Source Editor. 7I/Sfmqy"O
*/ -g]/Ko]2@$
1.o-2:]E
package com.tot.count; s{NEP/QQJ
import java.util.*; p)f OAr
/** +Q_X,gZ
* qBpv[m
* @author _{8f^@I"+
*/ sRE$*^i
public class CountCache { ];R5[%:5
public static LinkedList list=new LinkedList(); u'd+:uH
/** Creates a new instance of CountCache */ f62z9)`^
public CountCache() {} mq[(yR
public static void add(CountBean cb){ yc+#LZ~(a
if(cb!=null){ VBF3N5
;W
list.add(cb); K?BWl:^x
} {0lY\#qcE
} :bE ^b
} `=^29LC#
$hPAp}
CountControl.java qDM/
6xO
}zj w\
/* r6Lb0PzMf
* CountThread.java Ig'Y]%Z0
* '/\@Mc4T
* Created on 2007年1月1日, 下午4:57 FZ #ngrT
* WVftLIJ
* To change this template, choose Tools | Options and locate the template under ndOPD]A'
* the Source Creation and Management node. Right-click the template and choose U_ V0
* Open. You can then make changes to the template in the Source Editor. 8d-; ;V
*/ "monuErg&
1T%Y:0
package com.tot.count; kN`[Q$B
import tot.db.DBUtils; 0(Vbji
import java.sql.*; Z9i,#/
/** {v+i!a'+
* &s"&rFFO[
* @author wHBkaPO!
*/ a{L`C"rJ
public class CountControl{ K-)*S\<}
private static long lastExecuteTime=0;//上次更新时间 >L$y|8O
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 "}\2zub9
/** Creates a new instance of CountThread */ +#6WORH0S
public CountControl() {} (i|`PA
public synchronized void executeUpdate(){ -vGyEd7
Connection conn=null; +AZ=nMgW
PreparedStatement ps=null; ,M>W) TSH
try{ H'<9;bD -
conn = DBUtils.getConnection(); 3rZFN^
conn.setAutoCommit(false); Fw+JhIVP
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); hAOXOj1
for(int i=0;i<CountCache.list.size();i++){ V(L~t=k$
CountBean cb=(CountBean)CountCache.list.getFirst(); NSOWn]E
CountCache.list.removeFirst(); KA`1IW;
ps.setInt(1, cb.getCountId()); dY~3YD[
ps.executeUpdate();⑴ UX41/# 4
//ps.addBatch();⑵ .Y&_k
} 7WiVor$g-
//int [] counts = ps.executeBatch();⑶ 6](vnS;
conn.commit(); RoxzCFsI\
}catch(Exception e){ 3hmuF6y~
e.printStackTrace(); x&l?Cfvv=
} finally{ =P'=P0G
try{ !}"npUgE
if(ps!=null) { ]b'K
BAMy
ps.clearParameters(); Umv_{n`
ps.close(); ;G0~f9
ps=null; 5BS-q"
} <.l5>mgkCw
}catch(SQLException e){} Y3-Tg~/~W
DBUtils.closeConnection(conn); eoR@5OA&
} mZ/?uPIa
} ,'Y*e[
public long getLast(){ 6"|PJ_@P
return lastExecuteTime; |E53
[:p
} !H~!i.m'-
public void run(){ lDe9EJR
long now = System.currentTimeMillis(); 2N5N^S
if ((now - lastExecuteTime) > executeSep) { D?}LKs[
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;p BXAl
//System.out.print(" now:"+now+"\n"); r;y&Wa
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); jS5e"LMIq
lastExecuteTime=now; J%aW^+O
executeUpdate(); N?kXATB
} >%qGK-_
else{ ^M,t`r{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ;1NZY.pyc
} ppR_y
} U>e@m?
} 3 V8SKBS
//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 Uk S86`.
pA4/'7nCl
类写好了,下面是在JSP中如下调用。 01H3@0Q6
>/6v`
8F
<% /{>ds-;-
CountBean cb=new CountBean(); ,PJl32
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); S^I38gJd
CountCache.add(cb); qI<*Cze
out.print(CountCache.list.size()+"<br>"); eY\tO"Hc
CountControl c=new CountControl(); /p<mD-:.M
c.run(); ^P"t
"
out.print(CountCache.list.size()+"<br>"); I4m)5G?O2
%>