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: '~xiD?:
Q;kl-upn~8
CountBean.java qKs"L^b
n.1$p
/* uIR
* CountData.java _$KkSMA~_
* ;.7]zn.X]2
* Created on 2007年1月1日, 下午4:44 DO~~
* J,k.*t:
* To change this template, choose Tools | Options and locate the template under #,OiZQJC
* the Source Creation and Management node. Right-click the template and choose i"n1E@
* Open. You can then make changes to the template in the Source Editor. ~$YasFEz
*/ 5Z13s
e?;
package com.tot.count; :d@RN+U
y4Nam87;/?
/** B X O,
* |lh&l<=(f
* @author UL xgvq
*/ \mw5
~Rf;
public class CountBean { >dwY(a
private String countType; )Zrn?KM
int countId; |Rb8/WX
/** Creates a new instance of CountData */ #2%8@?_-M
public CountBean() {} TIn o"tc3
public void setCountType(String countTypes){ gKRlXVS
this.countType=countTypes; !iUT Re
} TtgsM}Fm
public void setCountId(int countIds){ $"3cN&
this.countId=countIds; xC2y/?
} _w7yfZLv+
public String getCountType(){ h-\+# .YP
return countType; *?o 'sTH
} 5w</Ga
public int getCountId(){ 9dp1NjOtAc
return countId; 3&B- w
} (>gb9n
} BuS[(
3*eS<n[uG
CountCache.java Jv~^hN2
s_U--y.2r(
/* ]F"@+_E
* CountCache.java {Vf].l:kn
* 2D"aAI<P
* Created on 2007年1月1日, 下午5:01 8>(/:u_x
* A9LVS&52
* To change this template, choose Tools | Options and locate the template under I %CrsEo
* the Source Creation and Management node. Right-click the template and choose au/5`
* Open. You can then make changes to the template in the Source Editor. 'Ge8l%p
*/ GsIqUM#R
JY$;m3h
package com.tot.count; JC7:0A^
import java.util.*; H)5" <=]
/** Oo9'
* C%"aj^u
* @author *Q;?p
hr
*/ Y\E7nll:.
public class CountCache { Pe`jNiI
public static LinkedList list=new LinkedList(); |zOwC9-6
/** Creates a new instance of CountCache */ aX.//T:':?
public CountCache() {} _Pn
1n
public static void add(CountBean cb){ (Z Q?1Qxo
if(cb!=null){ 2W;2._
list.add(cb); c=p!2jJ1K~
} LVJn2t^
} VhU,("&pm
} &,$N|$yK}|
ra^"Vr
CountControl.java Jl ?_GX}ZY
j-t"
/* :13u{5:th
* CountThread.java 18>v\Hi<
* K8h\T4
* Created on 2007年1月1日, 下午4:57 W?du ]
* F:LrQu
* To change this template, choose Tools | Options and locate the template under [$Jsel<T=
* the Source Creation and Management node. Right-click the template and choose 0m4'm<2m
* Open. You can then make changes to the template in the Source Editor. FPu$N d&\
*/ Tj!rAMQk
~F>'+9?Sn
package com.tot.count; fPG3$<Zr
import tot.db.DBUtils; }w{E<C(M
import java.sql.*; x}#N?d
/** 2g;Id.i>
* {N@Pk[!
* @author G}@a]EGm
*/ Xi!e=5&Pa
public class CountControl{ ~Sx\>wBlc
private static long lastExecuteTime=0;//上次更新时间 }+K=>.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 k{cPiY^
/** Creates a new instance of CountThread */ @6H 7
public CountControl() {} S]Aaf-X_
public synchronized void executeUpdate(){ J@qLBe(v
Connection conn=null; U"a7myB+jX
PreparedStatement ps=null; i_av_I-
try{ =sk#`,,:
conn = DBUtils.getConnection(); {5c]\{O?[
conn.setAutoCommit(false); j2mMm/kq\
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Qki?
>j"
for(int i=0;i<CountCache.list.size();i++){ I 1Yr{(ho
CountBean cb=(CountBean)CountCache.list.getFirst(); r"dR}S.Uf
CountCache.list.removeFirst(); ?h,.1Tb
ps.setInt(1, cb.getCountId()); KIY9?B=+
ps.executeUpdate();⑴ FhQb9\g
//ps.addBatch();⑵ ul!q)cPb{
} X#o;`QM
//int [] counts = ps.executeBatch();⑶ ts
r{-4V
conn.commit(); o+Q2lO5
}catch(Exception e){ -0<ZN(?|
e.printStackTrace(); SUD~@]N1
} finally{ q XB E3
try{ ~w}=Oby'y
if(ps!=null) { x\YVB',h
ps.clearParameters(); R0-Y2v
ps.close(); zO0K*s.yK
ps=null; c,#Nd@
} @[{5{ y
}catch(SQLException e){} rVp^s/A^;
DBUtils.closeConnection(conn); @?&
i
} IH.EvierJ
} f,ql8q(|J
public long getLast(){ j_S3<wEJ
return lastExecuteTime; *E-MJCv
} i#PR
Tbc
public void run(){ mB%m<Zo\U
long now = System.currentTimeMillis(); (
geV(zT
if ((now - lastExecuteTime) > executeSep) { VOT9cP^6
//System.out.print("lastExecuteTime:"+lastExecuteTime); /buj(/q^#
//System.out.print(" now:"+now+"\n"); nPH\Lra
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); t<%+))b
lastExecuteTime=now; !(y(6u#
executeUpdate(); Bf" ZmG9
} gl!ht@;>ak
else{ {~#d_!(
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 97pnq1b
} %1)J Rc
} zbfe=J4c
} m3XT8F*&
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 j?VHR$
V(Oi!(H;v
类写好了,下面是在JSP中如下调用。 S(0JBGC
S`vw<u4t
<% He&A>bA)z
CountBean cb=new CountBean(); V>ZDJW"G!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); rw?wlBEG%
CountCache.add(cb); 8yM8O
#S
out.print(CountCache.list.size()+"<br>"); }&%&0$%
CountControl c=new CountControl(); |*L/
m0'L
c.run(); 845\u&
out.print(CountCache.list.size()+"<br>"); (@S9>z4s
%>