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: lD$\t/8B
B^C5?
CountBean.java -fOBM 4
@ X5#?
/* ~'N+O K
* CountData.java zZP&`#TAy
* .>p.k*vU
* Created on 2007年1月1日, 下午4:44 R#!Urhh
* 7,Y+FZ
* To change this template, choose Tools | Options and locate the template under 7V&ly{</
* the Source Creation and Management node. Right-click the template and choose luJNdA:t&
* Open. You can then make changes to the template in the Source Editor. De<i
8/^=
*/ GjbOc
Kf`/ Gc!
package com.tot.count; rLA^ &P:
L$ZsNs+
/** PoD/i@
* &;U
F,
* @author p,14'HS%@
*/ I7W?}bR*6
public class CountBean { omI"xx
private String countType; 5m\)82s
int countId; qoEZ>
/** Creates a new instance of CountData */ .x1.` Y
public CountBean() {} tg7QX/KX
public void setCountType(String countTypes){ _ o==
this.countType=countTypes; TWdhl9Ot
} Tn?D~?a*O
public void setCountId(int countIds){ u/%Z0`X
this.countId=countIds; a\KM^jrCD
} cCcJOhk|d
public String getCountType(){ j9.%(*
return countType; iYGa4@/uM
} [X kWPx`
public int getCountId(){ B?ipo,2~{
return countId; Nzb=h/;
} k0D):
} B.~[m}
le6eorK8
CountCache.java 0Z{u;FI
DPfN*a-P(
/* ,nJCqX~/G
* CountCache.java EjP)e;
* .2y @@g
* Created on 2007年1月1日, 下午5:01 9H2mA$2jnE
* E,QD6<?[
* To change this template, choose Tools | Options and locate the template under AR c
* the Source Creation and Management node. Right-click the template and choose %!R\-Vej
* Open. You can then make changes to the template in the Source Editor. % -.V6}V
*/ _~;K]
-i]2b
package com.tot.count; ?8)k6:
import java.util.*; uM9Gj@_
/** [K1z/ea)V
* /as+ TU`A
* @author _5o5/@
*/ )"%J~:`h}
public class CountCache { **c"}S6:mC
public static LinkedList list=new LinkedList(); dJ~Occ 1~r
/** Creates a new instance of CountCache */ :wfN+g=
public CountCache() {} OX [r\
public static void add(CountBean cb){ Fe2t[y:8h
if(cb!=null){ ]+>Kl>@
list.add(cb); 0CI\Yd=
} %K0Wm#)
} jVna;o)
} 7?8+h
Ym2Ac>I4
CountControl.java q-S#[I+g
tO3#kV\,
/* IV%Rph>d
* CountThread.java z }Vg4\x&
* 0|,Ij$
* Created on 2007年1月1日, 下午4:57 67U6`9d
* &&C'\,ZK5
* To change this template, choose Tools | Options and locate the template under [S0wwWU |0
* the Source Creation and Management node. Right-click the template and choose P.djR)YI
* Open. You can then make changes to the template in the Source Editor. JO~62='J
*/ azG"Mt|7Z
b]*OGp4]5
package com.tot.count; }\1IsK~P
import tot.db.DBUtils; &td
import java.sql.*; N w/it*f
/** -}RGz_LO/
* "om[S :ai
* @author 8&CQx*
*/ !:v7SRUXb
public class CountControl{ $Qxy@vU
private static long lastExecuteTime=0;//上次更新时间 HTSk40V
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 m@YK8c#$
/** Creates a new instance of CountThread */ !PgwFJ
public CountControl() {} Us_1 #$p,
public synchronized void executeUpdate(){ AmrVxn4
Connection conn=null; %0'7J@W
PreparedStatement ps=null; {D8yqO A}
try{ Ged} qXn
conn = DBUtils.getConnection(); #Fkp6`Q$x
conn.setAutoCommit(false); <&tdyAT?&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); E0.o/3Gw6
for(int i=0;i<CountCache.list.size();i++){ - *qoF(/U
CountBean cb=(CountBean)CountCache.list.getFirst(); <KX+j,4
CountCache.list.removeFirst(); N l^uA
ps.setInt(1, cb.getCountId()); o* e'D7
ps.executeUpdate();⑴ DH)E9HL
//ps.addBatch();⑵ (4/W)L$
} lkJe7 +s
//int [] counts = ps.executeBatch();⑶ 5=1Ml50
conn.commit(); V?~!D p
}catch(Exception e){ |Z8Eu0RSb
e.printStackTrace(); BN6cu9a
} finally{ EtQ:x$S_
try{ 24\^{3nOK
if(ps!=null) { cI-@nV
ps.clearParameters(); *DvQnj
ps.close(); i/PL!'oq
ps=null; r(rT.D&
} u5Mg
}catch(SQLException e){} uvi&! )x
DBUtils.closeConnection(conn); T/:6Z
} H(Y 1%@
} T=CJUla
public long getLast(){ %eGI]!vf
return lastExecuteTime; *77Y$X##k
} q9c-UQB(!
public void run(){ }/Qj8l.
long now = System.currentTimeMillis(); ]1MZ:]k
if ((now - lastExecuteTime) > executeSep) { 0D0uzUD-
//System.out.print("lastExecuteTime:"+lastExecuteTime); u"8KH
u5C@
//System.out.print(" now:"+now+"\n"); #VxN [770
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <`NtTG
lastExecuteTime=now; h;R>|2A
executeUpdate(); @h(Z;
} bk]g}s
else{ E`]un.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7Dw.9EQ
} SAE'y2B*
} z'\BZ5riX<
} l
nJ
//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 ]l`V#Rd
>O0<u
类写好了,下面是在JSP中如下调用。 ,[3}t%Da
fP 3t0cp
<% PJ,G_+b!
CountBean cb=new CountBean(); (-VH=,Md
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); dJ>tM'G
CountCache.add(cb); 8!MVDp[|"
out.print(CountCache.list.size()+"<br>"); OHv9|&Tpl
CountControl c=new CountControl(); V6B[eV$D
c.run(); %g69kizoWi
out.print(CountCache.list.size()+"<br>"); 8Nx fYA
%>