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: 9`//^8G:=
%M|,b!eF
CountBean.java 2lKV#9"
Wo~vhv$E
/* l7{oi!
* CountData.java ^ci3F<?Q=
* 1?*
* Created on 2007年1月1日, 下午4:44 0[?ny`Y
* z7M_1%DEx
* To change this template, choose Tools | Options and locate the template under 4MuO1W-
* the Source Creation and Management node. Right-click the template and choose 2Qp Hvsl_
* Open. You can then make changes to the template in the Source Editor. E{^ XlY
*/ Rm1A>1a:
A\_ |un%
package com.tot.count; +
b$=[nfG
-x8nQ%X
/** :0)3K7Q
* {j5e9pg1L|
* @author cKb)VG^
*/ $D
v\
e
public class CountBean { r_e7a6
private String countType; =0;}K@(J
int countId; 4'4\,o
/** Creates a new instance of CountData */ iy.2A!f^.
public CountBean() {} ,lA.C%4au~
public void setCountType(String countTypes){ P}ok*{"J<>
this.countType=countTypes; Z[\O=1E,
} pD]0`L-HJU
public void setCountId(int countIds){ 0;4t&v7
this.countId=countIds; @_:]J1jw7
} ~_s?k3cd
public String getCountType(){ 'TH15r@
return countType; 6hZ@;Q=b
} G7--v,R1x
public int getCountId(){ ZCKka0*
return countId; bl_H4
} cLPkK3O\=
} /!^&;$A'
J_Ltuso
CountCache.java #ET/ =
8]4U`\k4
/* 6 3`{.yZ*z
* CountCache.java V-n&oCS+f
* SS`qJZ|w
* Created on 2007年1月1日, 下午5:01 F:y[@Yn
* F":r4`5D"K
* To change this template, choose Tools | Options and locate the template under `qd+f{Q
* the Source Creation and Management node. Right-click the template and choose b=~i)`
* Open. You can then make changes to the template in the Source Editor. D+_oVob\
*/ ~4P%%b0,o
K=!Bh*
package com.tot.count; fwK}/0%
import java.util.*; (b'B%rFO
/** [7_56\G4
* |#6QThK
* @author upj]6f"(
*/ .h0b~nI>>
public class CountCache { &>e-(4Xu
public static LinkedList list=new LinkedList(); N2.AKH
/** Creates a new instance of CountCache */ :Mm3
gW)
public CountCache() {} zIP6\u
public static void add(CountBean cb){
,g%&|FAP
if(cb!=null){ 5~mh'<:
list.add(cb); Z2im@c67{
} "D?z
} z]b>VpW:
} `tjH<
*tm0R> ?!
CountControl.java JXyM\}9-X
Qne/g}PD`
/*
~"UV]Udn
* CountThread.java (JM4R8fR&
* %tG*C,l]
* Created on 2007年1月1日, 下午4:57 22f`LoM
* )M__
t5L
* To change this template, choose Tools | Options and locate the template under \:'%9 x
* the Source Creation and Management node. Right-click the template and choose dCj,b$
* Open. You can then make changes to the template in the Source Editor. yHxosxd<*
*/ M33_ja +L
/-bO!RTwf
package com.tot.count; >A@Y$.
import tot.db.DBUtils; fN'HE#W1Xa
import java.sql.*; dt2$`X18
/** (@iMLuewK
* ^"J8r W6[
* @author QWMdn
*/ ('-JY
public class CountControl{ ;FZ@:%qDm
private static long lastExecuteTime=0;//上次更新时间 Sm~l:v0%
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 o]
mD"3_
/** Creates a new instance of CountThread */ 2h[85\4
public CountControl() {} x3PD1JUf
public synchronized void executeUpdate(){ J>u
7,
Connection conn=null; 6oF7:lt
PreparedStatement ps=null; h6} lpd
try{ pZtu&R%GU
conn = DBUtils.getConnection(); dnj}AVfQx
conn.setAutoCommit(false); hs}8xl
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `'V4PUe
for(int i=0;i<CountCache.list.size();i++){ EvOJ~'2 Y%
CountBean cb=(CountBean)CountCache.list.getFirst(); J!:SPQ
CountCache.list.removeFirst(); eds26(
ps.setInt(1, cb.getCountId()); #>j.$2G>
ps.executeUpdate();⑴ |j 6OM{@
//ps.addBatch();⑵ B" 3dQwQ
} Qx [t/~
//int [] counts = ps.executeBatch();⑶ qIld;v8w"g
conn.commit(); -WYAN:s
}catch(Exception e){ !qX_I db\
e.printStackTrace(); B/`
!K
} finally{ i86>]
try{ E*jP8 7g
if(ps!=null) { ?s:d[To6
ps.clearParameters(); 44-R!
ps.close();
<vXGi
ps=null; 8P=o4lO+
} F^hBtfz
}catch(SQLException e){} W"Gkq!3u{
DBUtils.closeConnection(conn); w:
>5=mfk
} Y[L-7^o@y
} q7"7U=W0
public long getLast(){ =2@B&
return lastExecuteTime; A'2w>8
} a{[x4d,z
public void run(){ 6P';DB
long now = System.currentTimeMillis(); U^Xm)lL
if ((now - lastExecuteTime) > executeSep) { )HX|S-qRU=
//System.out.print("lastExecuteTime:"+lastExecuteTime); YfRkwKjy(
//System.out.print(" now:"+now+"\n"); /{|fyKo\?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); F$[ U|%*
lastExecuteTime=now; o`Ta("9^
executeUpdate(); rD*sl}
} y
K"kEA[;
else{ %Qj;, #z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); %Q.&ZhB
} ZcaX'5}!S
} F+@5C:<?
} t*?0D\b
2
//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 %JLk$sP9y`
yrR1[aT
类写好了,下面是在JSP中如下调用。 HeG)/W?r
KCWc`Oz
<% {#{DH?=^)u
CountBean cb=new CountBean(); *V+j%^91}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); mW:!M!kk
CountCache.add(cb); !H ~<
out.print(CountCache.list.size()+"<br>"); W8]lBh5~:
CountControl c=new CountControl(); &8z[`JW,T
c.run(); hEw-
O;T0
out.print(CountCache.list.size()+"<br>"); og0*Nt+
%>