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: NUCiY\td
4o<*PPA1
CountBean.java Z7fg
25
MaO"#{i
/* gH[,Xx?BN!
* CountData.java Ojq]HM6f
* zJ+3g!
* Created on 2007年1月1日, 下午4:44 mzWP8Hlw
* l
_+6=u
* To change this template, choose Tools | Options and locate the template under hoenQ6N^:
* the Source Creation and Management node. Right-click the template and choose #uSK#>H_!
* Open. You can then make changes to the template in the Source Editor. e+. \pe\
*/ l4rMk^>>
LXj5R99S
package com.tot.count; 8$0\J _
wJe?t$ac?
/** %%%S"$t
* {T=52h=e
* @author fiVHRSX60
*/ jfD1
public class CountBean { WK0C
private String countType; t V03+&jF
int countId; kZLMtj-
/** Creates a new instance of CountData */ Tk*w3c"$
public CountBean() {} T>A{qu
public void setCountType(String countTypes){ dH\XO-Z7v
this.countType=countTypes; 03k?:D+5
} SHV4!xP-V
public void setCountId(int countIds){ !4WEk
this.countId=countIds; T dk
,&8
} 5{K}?*3hJ
public String getCountType(){ *FK`&(B+}
return countType; 6.5wZN9<|
} %T!J$a)qf
public int getCountId(){ -Fxmsi
return countId; tu0aD%C
} 2#vv$YD
} G,XPT,:%
9XLFHV("
CountCache.java s
=Umj'1k
fuUm}N7
/* Md,pDWb
* CountCache.java A(8n
* %g3,qI
* Created on 2007年1月1日, 下午5:01 u,1}h L
* fY,|o3#
* To change this template, choose Tools | Options and locate the template under 3GH(wSv9\
* the Source Creation and Management node. Right-click the template and choose }tG3tz0%fX
* Open. You can then make changes to the template in the Source Editor. "Pz}@=
*/ ;
A,#;%j
;@3FF
package com.tot.count; 1[;;sSp
import java.util.*; *|% ^0#$c
/** P[ r];e
* C3'rtY.
* @author nV*y`.+
*/ zR;X*q"T$4
public class CountCache { e`K)_>^n#
public static LinkedList list=new LinkedList(); i3VW1~ .8
/** Creates a new instance of CountCache */ EH*o"N`!r
public CountCache() {} l[GOs&D1
public static void add(CountBean cb){ p\p\q(S">
if(cb!=null){ Q=uR Kh
list.add(cb); TUIk$U?/I
} ~utJB 'gr
} 7.Kc:7
} 23!;}zHp
ccFn.($p?,
CountControl.java -r7]S
n5-)/R[z
/* )~J>X{hy
* CountThread.java nmU_N:Y
* FR[ B v
* Created on 2007年1月1日, 下午4:57 8eBOr9l+j
* Q/ms]Du
* To change this template, choose Tools | Options and locate the template under fBn"kr;
* the Source Creation and Management node. Right-click the template and choose {c?JuV4q?
* Open. You can then make changes to the template in the Source Editor. y&m0Lz53Z
*/ YgUH'P-
I){\0vb@
package com.tot.count; ^ KK_qC
import tot.db.DBUtils; :~Q!SL N
import java.sql.*; N,dT3we
/** qBV x6MI
* oX@ya3!Pz
* @author xT&(n/
*/ B(?Yw>Xd[
public class CountControl{ }v9\F-0>Q
private static long lastExecuteTime=0;//上次更新时间 @`opDu!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 fKC3-zm
/** Creates a new instance of CountThread */ o%{'UG
public CountControl() {} :F,O
public synchronized void executeUpdate(){ RO;Bl:x4
Connection conn=null; gWABY%!}
PreparedStatement ps=null; `@d<n
try{ u]
:m"LM
conn = DBUtils.getConnection(); 7(M(7}EKA
conn.setAutoCommit(false); 7!,YNy%
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .:p2Tbo
for(int i=0;i<CountCache.list.size();i++){ '{I_\~*
CountBean cb=(CountBean)CountCache.list.getFirst(); E:zF/$tG
CountCache.list.removeFirst(); J:uW`R
ps.setInt(1, cb.getCountId()); _=ua6}Xp
ps.executeUpdate();⑴ bNFLO
Q
//ps.addBatch();⑵
~>O)
} [,n c
//int [] counts = ps.executeBatch();⑶ @`tXKP$so
conn.commit(); 2!&&|Mh}
}catch(Exception e){ Q9}dHIe1E
e.printStackTrace(); 5D M"0
} finally{ du$|lxC
try{ ;.xoN|Per
if(ps!=null) { 1Je9,dd6
ps.clearParameters(); r`)L~/
ps.close(); ReiB $y6
ps=null; |KB0P@=a
} AL$&|=C-$
}catch(SQLException e){} (feTk72XX
DBUtils.closeConnection(conn); @(P=Eh
} x^Yl*iq
} ]yjl~3
public long getLast(){ i)#:qAtP*
return lastExecuteTime; Rqwzh@}
} b:qY gg
public void run(){ e8YMX&0%
long now = System.currentTimeMillis(); ^pM+A6
XY
if ((now - lastExecuteTime) > executeSep) { zF5uN:-s
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1ygpp0IGJ
//System.out.print(" now:"+now+"\n"); *:i1Lv@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); |ZodlYF
lastExecuteTime=now; jx acg^c
executeUpdate(); *'ZB*>
} pJN$ {
else{ Y#!h9F
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); nG_6oe*=I
} %OgS^_tu
} 9qS"uj
} qY\f'K}Q*
//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 T~h5B(J;
n$xQ[4eH)
类写好了,下面是在JSP中如下调用。 3\T2?w9u(
42>Ge>#F
<% ;n|^1S<[
CountBean cb=new CountBean(); NEa>\K<\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); j~j\\Y
CountCache.add(cb); 1-RIN}CSd
out.print(CountCache.list.size()+"<br>"); jqr1V_3(
CountControl c=new CountControl(); ;[RZ0Uy=
c.run(); Be+0NXLVy
out.print(CountCache.list.size()+"<br>"); ?5kHa_^
%>