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: YBCjcD[G
]EcZ|c7o9y
CountBean.java 0>;#vEF*1
{x4[Bx1
/* FezW/+D
* CountData.java b c4x"]!
* w@ 5/mf?
* Created on 2007年1月1日, 下午4:44 Hb+#*42v
* 8 (KfX%
* To change this template, choose Tools | Options and locate the template under 0;H6b=
* the Source Creation and Management node. Right-click the template and choose t?
A4xk
* Open. You can then make changes to the template in the Source Editor. y;Zfz~z
*/ yki
k4MeB
^sOm7S {
package com.tot.count; ~fF}
\O8f~zA{G
/** vg.%. ~!9
* g
Oj5c
* @author cMWO_$
*/ qQcC[50
public class CountBean { bZ9NnSuH
private String countType; }J?fJ(
int countId; I:_*8el&d
/** Creates a new instance of CountData */ Q Bw
ZfX
public CountBean() {} \l:g{GnoT
public void setCountType(String countTypes){ 0xxzhlKNL
this.countType=countTypes; A]+h<Y~}
} ],YYFU}
public void setCountId(int countIds){ u#M)i30j
this.countId=countIds; /kA19E4
} H/3Zdj 9
public String getCountType(){ r^E]GDz
return countType; 4ufLP DH
} q-G|@6O
public int getCountId(){ (K6`nWk2
return countId; @Y<tH,*
} =.X?LWKY
} f>5RAg
n2{{S(N
CountCache.java @."o:K
e]
K=Nm
/* BR^J y<^F'
* CountCache.java 6)U&XWH0
* {g- DM}q
* Created on 2007年1月1日, 下午5:01 fBgKX?Y
* CdDd+h8
* To change this template, choose Tools | Options and locate the template under rH9}nL
* the Source Creation and Management node. Right-click the template and choose <s>/< kW:
* Open. You can then make changes to the template in the Source Editor. 0#[f2X62B
*/ Uo}&-$ B
Di'u%r
package com.tot.count; '=
<`@
import java.util.*; <gdgcvd
/** b H?qijrC
* 8>{W:?I
* @author !NYM(6!(
*/ daIL> c"
public class CountCache { ?GNF=#=M
public static LinkedList list=new LinkedList(); "x;k'{S
/** Creates a new instance of CountCache */ ,GJ>vT)
public CountCache() {} T4=3VrS
public static void add(CountBean cb){ E)O|16f|>
if(cb!=null){ K)`:v|d
list.add(cb); 1 j12Qn@]
} bez'[Y{
} R5eB,FN
} (Q5@MfK`
T#n1@FgC
CountControl.java zf,%BI[Hr
NceB'YG|
/* +z=%89GJ
* CountThread.java ;hA7<loY
* %Sn 6*\z
* Created on 2007年1月1日, 下午4:57 '95E;RV&
* Yc82vSG'
* To change this template, choose Tools | Options and locate the template under 0O#B'Uu
* the Source Creation and Management node. Right-click the template and choose !
F <] T
* Open. You can then make changes to the template in the Source Editor. =*g$#l4
*/ l}0V+
l-S'ATZ0p
package com.tot.count; T5azYdzJy
import tot.db.DBUtils; QG|GXp_q`
import java.sql.*; U>_IYT
/** 9*|3E"Vr
* %md^S
|
* @author V 7l{hEo3?
*/ }11`98>B6:
public class CountControl{ %i&/$0.8
private static long lastExecuteTime=0;//上次更新时间 ^+as\
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 tw/#ENo
/** Creates a new instance of CountThread */ bqrJP3
public CountControl() {} qggk:cN1
public synchronized void executeUpdate(){ rocB"0
Connection conn=null; (.,'}+1
PreparedStatement ps=null; P-+M,>vNy[
try{ ZS XRzH~0
conn = DBUtils.getConnection(); lU$4NUwM
conn.setAutoCommit(false); FKox0Jmh=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @?Gw|bP
for(int i=0;i<CountCache.list.size();i++){ TH>?Gi)"
CountBean cb=(CountBean)CountCache.list.getFirst(); o8'Mks
CountCache.list.removeFirst(); V5O=iMP
ps.setInt(1, cb.getCountId()); ySQ-!fQnP
ps.executeUpdate();⑴ I/HV;g:#
//ps.addBatch();⑵ K3rBl!7v
} )Ig+uDGk
//int [] counts = ps.executeBatch();⑶ u`Z0{d
conn.commit(); zr.+'
}catch(Exception e){ nuSN)}b<Q
e.printStackTrace(); Ug7`ez4vw
} finally{ `z}vONXpAX
try{ *
-KJh_
if(ps!=null) { j /H>0^
ps.clearParameters(); c6,s+^^
ps.close(); l
Io9,Ke
ps=null; F#1 Kk#t
} d1V^2Hb?
}catch(SQLException e){} 5L-lpT8P
DBUtils.closeConnection(conn); [0u.}c;(
} EmX>T>~#D
} v7;J%9=0D`
public long getLast(){ ;%u_ ;,((
return lastExecuteTime; Tr8AG>
} 2(m85/Hr\;
public void run(){ RCBf;$O
long now = System.currentTimeMillis(); "x(>Sj\%I
if ((now - lastExecuteTime) > executeSep) { O3kg
//System.out.print("lastExecuteTime:"+lastExecuteTime); ~h)@e\Kc
//System.out.print(" now:"+now+"\n"); u C,"5C
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]C16y.
~e
lastExecuteTime=now; ;&Bna#~B
executeUpdate(); U*3AM_w
} R:'Ou:Mh
else{ )MWUS;O<
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); A%Bgp?B
} z\fW )/
} qoC]#M$oo#
} qzA`d
5rX
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 C8IkpAD
R_1)mPQ^P
类写好了,下面是在JSP中如下调用。 ,VNi_.W0
iHAU|`'N)
<% b7B+eN ?z
CountBean cb=new CountBean(); :}y9$p
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /&PKCtm&~
CountCache.add(cb); yoBgr7gS
out.print(CountCache.list.size()+"<br>"); ;n`R\NO9
CountControl c=new CountControl(); /?KtXV>]
c.run(); ;V_.[aX
out.print(CountCache.list.size()+"<br>"); B_{HkQ.PW
%>