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: V21njRS
%%cHoprDa
CountBean.java Cuc$3l(%
Agrp(i"\@
/* kD[ r.Dma
* CountData.java nI0[;'Hn,
* Tr^nkD{
* Created on 2007年1月1日, 下午4:44 k1VT /u
* :8A!HI}m{
* To change this template, choose Tools | Options and locate the template under ~q&pF"va8
* the Source Creation and Management node. Right-click the template and choose .'a&33J
* Open. You can then make changes to the template in the Source Editor. )]#aa uC+
*/ Z@Ae$ '9H
5XLs} :
package com.tot.count; nk3y"ne7
_,</1~.
/**
xG;-bJu
* *'"^NSJ
* @author |AC1\)2tT
*/ '_b.\_s-d
public class CountBean { /*|oL#hK
private String countType; ~{}#)gGU
int countId; Y<0 4RV
/** Creates a new instance of CountData */ xnE|Umz
public CountBean() {} HNL42\Kz!
public void setCountType(String countTypes){ f{0F|w<gf
this.countType=countTypes; GU Q{r!S
} 5s?Hxn
public void setCountId(int countIds){ _{jjgQJ5
this.countId=countIds; "`asFg
} 1He{v#
public String getCountType(){ @AYRiOodi
return countType; J~(Wf%jM~
} ;\MW$/[JCy
public int getCountId(){ Hi]cxD*`
return countId; mw5?[@G-
} WL{(Ob
} h_d<!
/pp1~r.s?>
CountCache.java j1 =`|
cwV]!=RtO
/* 5[n(7;+gw
* CountCache.java gl&5l1&
* h~wi6^{&Y
* Created on 2007年1月1日, 下午5:01 3Tq\BZ
* ^9-&o
* To change this template, choose Tools | Options and locate the template under X>?b#Eva
* the Source Creation and Management node. Right-click the template and choose n&A'C\
* Open. You can then make changes to the template in the Source Editor. ^T~gEv
*/ ~zHg[X*
B^%1Rpcn
package com.tot.count; -+t]15
import java.util.*; i_][PTH
/** s}onsC
* dJ?XPo"Cm=
* @author
y<C<_2
*/ cQ:"-!ff
public class CountCache { gT/@dVV
public static LinkedList list=new LinkedList(); RmrL^asg
/** Creates a new instance of CountCache */ -)vEWn$3<
public CountCache() {} 2YuN~-
public static void add(CountBean cb){ %&
_V0R\k
if(cb!=null){ exdx\@72
list.add(cb); nADX0KI
} !`bio cA
} ,7XtH>2s
} SR*wvQnOx
H'F6$ypoS
CountControl.java >%E([:$A
PQ|69*2G
/* 7w;O}axI
* CountThread.java 2BCtJ`S`
* V<HU6w
* Created on 2007年1月1日, 下午4:57 5PcJZi^.l
* tRpEF2
* To change this template, choose Tools | Options and locate the template under 2&Nb
* the Source Creation and Management node. Right-click the template and choose $BmmNn#
* Open. You can then make changes to the template in the Source Editor. !.1%}4@Q]
*/ NA,CZ
c#N<"cy>
package com.tot.count;
'8j$';&`
import tot.db.DBUtils; HG'{J ^t
import java.sql.*; 7*DMVok:
/** 1}ZKc=Pfu
* (6v(9p
* @author Yl;^ k0ZI
*/ 09o~9z0
public class CountControl{ }IEbyb
private static long lastExecuteTime=0;//上次更新时间 G;3~2^lB\
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zY+Fl~$S
/** Creates a new instance of CountThread */ ?[x49Ux,P
public CountControl() {} {K#NB_*To
public synchronized void executeUpdate(){ 0ult7s}
Connection conn=null; /J)l /oI
PreparedStatement ps=null; Jw~( G9G
try{ rwIeqV{:
conn = DBUtils.getConnection(); i*R,QN)
conn.setAutoCommit(false); fri0XxF
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); mW%?>Z1=>d
for(int i=0;i<CountCache.list.size();i++){
kj5Q\vr)
CountBean cb=(CountBean)CountCache.list.getFirst(); BK,sc'b
CountCache.list.removeFirst(); l<(Y_PE:
ps.setInt(1, cb.getCountId()); ":3 VJ(eY
ps.executeUpdate();⑴ N)% ;jh:T
//ps.addBatch();⑵ drwgjLC+
} 3\;27&~gV
//int [] counts = ps.executeBatch();⑶
x{}z ;yG
conn.commit(); v6\F
Q9|t
}catch(Exception e){ 9dh>l!2
e.printStackTrace(); (J"T]-[
} finally{ FI8Oz,
try{ A$g+K,.l
if(ps!=null) { [~D|peM3
ps.clearParameters(); :`)~-`_
ps.close(); M\b")Tu{0
ps=null; PN+G:Qv
} hl&-\ dc+
}catch(SQLException e){} g/=K.
DBUtils.closeConnection(conn); }Vu\(~
} 6I_Hd>4
} -oz`"&%
public long getLast(){ ^BZkHAp
return lastExecuteTime; 9]$8MY
} ,D6v4<jh
public void run(){ m\/(w_/?
long now = System.currentTimeMillis(); vhr+g 'tf
if ((now - lastExecuteTime) > executeSep) { }G$]LWgQx
//System.out.print("lastExecuteTime:"+lastExecuteTime);
yz+, gLY
//System.out.print(" now:"+now+"\n"); t)oa pIeIe
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "x'),
lastExecuteTime=now; h x6;YV
executeUpdate(); h?\2_s
} S~$'WA
else{ ea=83 Zj
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Wi n8LOC
} 0%s|Zbo!>
} &$`hQgi
} {+zJI-XN/
//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 *5$&`&,
%[<Y9g,:Q
类写好了,下面是在JSP中如下调用。 o-7>eE}+
h06ku2Q
<% =R*Gk4<Y
CountBean cb=new CountBean(); v;y0jD#b
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xa( m5P
CountCache.add(cb); V@=V5bZLs
out.print(CountCache.list.size()+"<br>"); %,b X/!
CountControl c=new CountControl(); &Y@#g9G
c.run(); 3HyhEVR-#~
out.print(CountCache.list.size()+"<br>"); M4Z@O3OIE
%>