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: Qn2&nD%zi
M X]n&
CountBean.java KwVbbC3
8zq=N#x
/* *|HY>U.
* CountData.java eS){1
*
C9)@jK%
* Created on 2007年1月1日, 下午4:44 *lJxH8 \
* J]r^W)O
* To change this template, choose Tools | Options and locate the template under m.0*NW
* the Source Creation and Management node. Right-click the template and choose u:
* Open. You can then make changes to the template in the Source Editor. |k00Z+O(
*/ z\4.Gm-
`uTmw^pZX
package com.tot.count; 1G`Pmh@
f*
wx<
/** fI|$K)K
* + LJ73
!
* @author |JsZJ9W+J
*/ _,*r_D61S
public class CountBean { `kSZX:=};
private String countType; RT8 ?7xFc
int countId; 5#z1bu
/** Creates a new instance of CountData */ ZYNsHcTY
public CountBean() {} M
D#jj3y
public void setCountType(String countTypes){ AQ^u
this.countType=countTypes;
05 ^h"
} :Llb< MY2
public void setCountId(int countIds){ EKN~H$.
this.countId=countIds; ]eV8b*d6
} K:WDl;8(d
public String getCountType(){ 'Z]w^<
return countType; 1{.9uw"2S
} X5w$4Kj&4l
public int getCountId(){ ksm~<;td
return countId; ,`sv1xwd
} iN.n8MN=I
} zKK9r~ M
HK%7g
CountCache.java l%=;
MpOc
/* V]?R>qhgu
* CountCache.java l}P=/#</T
* Zb#u0Tq
* Created on 2007年1月1日, 下午5:01 3__-nV
* /zox$p$?h
* To change this template, choose Tools | Options and locate the template under `
G
kX
* the Source Creation and Management node. Right-click the template and choose {2gwk8
* Open. You can then make changes to the template in the Source Editor. ,/U6[P_C5
*/ :~SyL !
J9 I:Q<;
package com.tot.count; :Iz8aQ
import java.util.*; WfRXP^a
/** 2>59q$|
* JsS-n'gF'
* @author 0IWf!Sk
]
*/ Gp\
kU:}&
public class CountCache { 4{Z)8;QX
public static LinkedList list=new LinkedList(); 7x8
yxE
/** Creates a new instance of CountCache */ (QiAisE
public CountCache() {} MfkN]\Jyw
public static void add(CountBean cb){ fd9k?,zM
if(cb!=null){ L\iFNT}g`
list.add(cb); V G~Vs@c(
} rW#T
vUn
} lr$zHI7_`
} N)Z?Z+}h
L4l!96]a
CountControl.java #|``ca54B
bQ5\ ]5M
/* Ht&YC<X
* CountThread.java &>}5jC.I
* I*^Ta{j[
* Created on 2007年1月1日, 下午4:57 a09<!0Rp
* 3
8`<:{^Y
* To change this template, choose Tools | Options and locate the template under xd0 L{ue.
* the Source Creation and Management node. Right-click the template and choose k|f4Cf,
* Open. You can then make changes to the template in the Source Editor. %N_%JK\{@
*/ {f p[BF
^dxTm1Z
package com.tot.count; 8a"%0d#
import tot.db.DBUtils; #)VF3T@#'
import java.sql.*; a-J.B.A$Z/
/** Yz93'HDB
* J|rq*XD}q
* @author d<x7{?~.DK
*/ AT|3:]3E
public class CountControl{ v(%*b,^
private static long lastExecuteTime=0;//上次更新时间 -H-~;EzU
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 rU(+T0t?I
/** Creates a new instance of CountThread */ A+?`?pOm&
public CountControl() {} Uoix
public synchronized void executeUpdate(){ 2 8u_!f[
Connection conn=null; h
zn6kbv
PreparedStatement ps=null; Ssg&QI
try{ YZJyk:H\
conn = DBUtils.getConnection(); 9-m=*|p
conn.setAutoCommit(false); wwcBsJ1{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^LzF@{ G
for(int i=0;i<CountCache.list.size();i++){ _h1mF<\ X^
CountBean cb=(CountBean)CountCache.list.getFirst(); S$XSei_q
CountCache.list.removeFirst(); _GPl gp:
ps.setInt(1, cb.getCountId()); ,9
a
ps.executeUpdate();⑴ J9S>yLQK
//ps.addBatch();⑵ *DhiN
} MnW+25=N
//int [] counts = ps.executeBatch();⑶ {BU;$
conn.commit(); B#1;r-^P<
}catch(Exception e){ IEvdV6{K
e.printStackTrace(); 8*a&Jl
} finally{ `~q <N
try{ Yu2Bkq+
if(ps!=null) { ht}wEvv
ps.clearParameters(); ~WV"SaA)*U
ps.close(); &PtJ$0%q
ps=null; "@8li^
} IMONgFBS
}catch(SQLException e){} '@P^0+B!(.
DBUtils.closeConnection(conn); y1L,0 ]
} +m,yA mEEd
} 2^yU ~`#
public long getLast(){ iO;
7t@]-
return lastExecuteTime; ,~W|]/b<q
} @pU)_d!pJ
public void run(){ %ULr8)R;
long now = System.currentTimeMillis(); Dv`c<+q(#
if ((now - lastExecuteTime) > executeSep) { SMK_6?MZ
//System.out.print("lastExecuteTime:"+lastExecuteTime); e\75:oQ
//System.out.print(" now:"+now+"\n"); ;i:d+!3XwC
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); RViuJ;
lastExecuteTime=now; q'MZ R'<@
executeUpdate(); ;gr9/Vl
} IIx#2r
else{ uY'HT|@:{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^K@C"j?M/
} ]e@Oiq
} Pk)1WK7E
} -A!%*9Z
//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 \dQNLLg/
geCM<]
类写好了,下面是在JSP中如下调用。 K",N!koj
r]36zX v
<% jrh43
\$*
CountBean cb=new CountBean(); nzeX[*
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); JqiP>4Uwm^
CountCache.add(cb); jo@J}`\Zt
out.print(CountCache.list.size()+"<br>"); 8Uxne2e
CountControl c=new CountControl(); q> C'BIr
c.run(); V3j= Kf
out.print(CountCache.list.size()+"<br>"); 8)I^ t81
%>