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: {KpH|i
ttAVB{kdo
CountBean.java (fk, 80
2
Zjb/
/* G4iLCcjY
* CountData.java n%MYX'0
* !EmR (x
* Created on 2007年1月1日, 下午4:44 EB3o8
* ]RrP !|^
* To change this template, choose Tools | Options and locate the template under _G}CD|Kx
* the Source Creation and Management node. Right-click the template and choose }r<@o3t
* Open. You can then make changes to the template in the Source Editor. \Q?|gfJH
*/ M\.T 0M_
sKG~<8M}
package com.tot.count; :86luLFm
7p>-oR"
/** Uc4L|:
* )r6SGlE[Y
* @author {, *Y
*/ s=%+o&B
public class CountBean { XdIVMXLL\
private String countType; J%O4IcE
int countId; tx1m36a"
/** Creates a new instance of CountData */ b\|p
public CountBean() {} "/K&qj
public void setCountType(String countTypes){ ow$l!8
this.countType=countTypes; @>nk^l
} `0XbV A
public void setCountId(int countIds){ 3N*C]
this.countId=countIds; Wk6&TrWlY
} O8N0 ]Mz
public String getCountType(){ L?C~
qS2g
return countType; @=#s~ 3
} Z*aU2Kr`;
public int getCountId(){ Hg_
XD,
return countId; ,zw=&)W1
} _v=WjN
} =LY^3TlDj
}J'wz;t1
CountCache.java y*Q-4_%,
!3Z|!JY
/* {ZEXlNPww
* CountCache.java )bU")
* _"bvT?|
* Created on 2007年1月1日, 下午5:01 $<%
nt
* -t'oW*kdL
* To change this template, choose Tools | Options and locate the template under vk+%#w
* the Source Creation and Management node. Right-click the template and choose ZjW| qb
* Open. You can then make changes to the template in the Source Editor. !enz05VW6.
*/ EjE`S_i=
XTaWd0Y
package com.tot.count; d]~1.i
import java.util.*; *xTquV$
/** +9rbQ?'
* 6U9Fa=%>}
* @author ayz1i:Q|
*/ |/\1nWD
public class CountCache { $v@$oPmMj
public static LinkedList list=new LinkedList(); =V]i?31[
/** Creates a new instance of CountCache */ Q09~vFBg
public CountCache() {} 58'y~Ou
public static void add(CountBean cb){ H>X1(sh#}
if(cb!=null){ 7tKft
list.add(cb); sZBO_](S
} g}r5ohqC#
} 3^yWpSC
} [y;ZbfMP|o
*LdH/C.LIf
CountControl.java 'c(Y")QP
,5uDEXpt{
/* ,,wx197XeD
* CountThread.java ;OqLNfU3y
* #f;1f8yrN
* Created on 2007年1月1日, 下午4:57 zn$Ld,
* <%uZwk>#
* To change this template, choose Tools | Options and locate the template under \1D,Kx;Cb
* the Source Creation and Management node. Right-click the template and choose .h^Ld,Chj
* Open. You can then make changes to the template in the Source Editor. NVZNQ{
*/ 1U9N8{xg9
1+c(G?Ava
package com.tot.count; *]?YvY
import tot.db.DBUtils; }mZ*f y0t
import java.sql.*; >(KUYX?p
/** 1RHH<c%2n
* t1g%o5?;
* @author @|A&\a-"J
*/ |ema-pRC
public class CountControl{ urjp&L&
private static long lastExecuteTime=0;//上次更新时间 &Sp:?I-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 RW8u0 ?b
/** Creates a new instance of CountThread */ <{Wa[1D
public CountControl() {} 8k'em/M~
public synchronized void executeUpdate(){ 4>`w9
Connection conn=null; bGO_y]Pc
PreparedStatement ps=null; Qnh1su5
try{ HV(*6b@
conn = DBUtils.getConnection(); 4zbV' ]
conn.setAutoCommit(false); io_64K+K
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b?L43t ,
for(int i=0;i<CountCache.list.size();i++){ iPNsEQ0We
CountBean cb=(CountBean)CountCache.list.getFirst(); gipRVd*TA
CountCache.list.removeFirst(); baG I(Dk
ps.setInt(1, cb.getCountId()); k-0e#"B
ps.executeUpdate();⑴ Kx!|4ya,
//ps.addBatch();⑵ ?KW?] o
} 8#-}3~l[
//int [] counts = ps.executeBatch();⑶ :$d 3a"]
conn.commit(); 1nG"\I5N}
}catch(Exception e){ 0_izTke
e.printStackTrace(); y%Ah"UY
} finally{ -q|M=6gOs
try{ c3-bn #
if(ps!=null) { HXo'^^}q;
ps.clearParameters(); 5|z[%x~f
ps.close(); lR^Qm|
ps=null; 6
VDF@V$E
} zxHfQ(
}catch(SQLException e){} /tP
DBUtils.closeConnection(conn); $"1&!
} ||NCVGJG
} C.p*mO&N
public long getLast(){ '11h Iu=:
return lastExecuteTime; Hb4rpAeP
} +O6@)?pI
public void run(){ BtZm_SeA
long now = System.currentTimeMillis(); -ZJ:<
if ((now - lastExecuteTime) > executeSep) { gRSG[GMV
//System.out.print("lastExecuteTime:"+lastExecuteTime); H-lRgJdc
//System.out.print(" now:"+now+"\n"); \/zS@fz
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); N`fY%"5U>
lastExecuteTime=now; Os+=}
executeUpdate(); ]UTP~2N
} /m:}rD
else{ 2N#L'v@g=+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); T3 Fh7S /
} :6{HFMf"
} |3@]5f&
} 'KG`{K$
//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 9a unv
IC~D?c0H:
类写好了,下面是在JSP中如下调用。 E ..[F<5
1Btf)y'
<% dno*Usx5d0
CountBean cb=new CountBean(); ,B><la87
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Ho|n\7$
CountCache.add(cb); uqH;1T;s
out.print(CountCache.list.size()+"<br>"); un=)k;oh
CountControl c=new CountControl(); 6!N&,I
c.run(); A}# Mrb
out.print(CountCache.list.size()+"<br>"); -B!pg7>'##
%>