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: HUv/ ~^<
7BK0}sxO
CountBean.java M42Ssn)
U |Jo{(Y
/* @Z\,q's
* CountData.java ][9%Kl*%@p
* JGsx_V1t
* Created on 2007年1月1日, 下午4:44 1DE<rKI
* 2.l Z:VLN
* To change this template, choose Tools | Options and locate the template under ^Eb.:}!D6
* the Source Creation and Management node. Right-click the template and choose O4cr*MCb5
* Open. You can then make changes to the template in the Source Editor. @` 1Ds
*/ *E/`KUG]
|
r&k48@
package com.tot.count; rvbLyv;~
&]v4@%<J
/** vY${;#~|
* M^r1S
* @author [<g?WPCcC
*/ .<x&IJ /
public class CountBean { Mn2QZp4
private String countType; j3{I /m
int countId; s;S?;(QI
/** Creates a new instance of CountData */ F`Q[6"<a
public CountBean() {} uW@oyZUj
public void setCountType(String countTypes){ :(!`/#6H
this.countType=countTypes; aWWU4xe
} mKL<<L[
public void setCountId(int countIds){ Li/O
this.countId=countIds; toya fHf
} v9w'!C)b
public String getCountType(){ i|w81p^o
return countType; (e!0]Io@
} J'SZ
public int getCountId(){ u09:Z{tL;@
return countId; Q<^Tl(`/N?
} nrxo&9[@n
} 0=* 8
\N!AXD
CountCache.java '=nQ$/!q
% NA9{<I
/* p?7v$ev_
* CountCache.java ftvG\T f
* ~sl{ |E
* Created on 2007年1月1日, 下午5:01 2Ga7$q
* hb zC#@q
* To change this template, choose Tools | Options and locate the template under wKZ$iGMbz
* the Source Creation and Management node. Right-click the template and choose \ 3wfwu.q
* Open. You can then make changes to the template in the Source Editor. j9?}j#@
*/ EQb7-vhg
5!DBmAB
package com.tot.count; B$ajK`x&I
import java.util.*; %Y<| ;0v
/** 0-HqPdjR
* )0"wB
* @author -Zf@VW,NI
*/ ;aI[=?<x
public class CountCache { Zhh2v>QOy
public static LinkedList list=new LinkedList(); 8/i!' 0r\
/** Creates a new instance of CountCache */ M=FxB;v
public CountCache() {} h]+C.Eqnt#
public static void add(CountBean cb){ Ne8Cgp
if(cb!=null){ L+Xc-uv["p
list.add(cb); 5][Ztx
} 5R@
} \`oT#|0
} q|o}+Vr
xO^:_8=&:
CountControl.java v(B<Nb
^W'fA{sr
/* e+$p9k~
* CountThread.java *.sVr7=j
* 3 Nreqq
* Created on 2007年1月1日, 下午4:57 f&eK|7J_Yf
* WG6FQAo^8
* To change this template, choose Tools | Options and locate the template under f,V<;s
* the Source Creation and Management node. Right-click the template and choose @ezH'y-v
* Open. You can then make changes to the template in the Source Editor. sYe?M,
*/ {1V($aBl
"!Uqcay-
package com.tot.count; !c}O5TI|#
import tot.db.DBUtils; #MX'^RZ>2
import java.sql.*; =|M>l
/** ,Sq/y~
* ohF JZ'
* @author F~%]6^$w
*/ //T>G_1
public class CountControl{ )PG6gZYW
private static long lastExecuteTime=0;//上次更新时间 T]t+E'sQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 A )^`?m3
/** Creates a new instance of CountThread */ GN ]cDik
public CountControl() {} ]ndvt[4L
public synchronized void executeUpdate(){ 9xO#tu]
Connection conn=null; $ACvV"b
PreparedStatement ps=null; iYDEI e
try{ [`{Z}q&
conn = DBUtils.getConnection(); SSz~YR^}Sr
conn.setAutoCommit(false); bvv|;6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ),U X4%K=
for(int i=0;i<CountCache.list.size();i++){ Gb8D[1=u=
CountBean cb=(CountBean)CountCache.list.getFirst(); r\b3AKrIN
CountCache.list.removeFirst(); mQCeo}7N5
ps.setInt(1, cb.getCountId()); u.mJQDTH
ps.executeUpdate();⑴ jNLw=
//ps.addBatch();⑵ AvxfI"sp
} +=q$ x Ia
//int [] counts = ps.executeBatch();⑶ Xf02"PXC
conn.commit(); LQtj~c>X-|
}catch(Exception e){ b7NM#Hb
e.printStackTrace(); P;P%n
} finally{ g .onTFwN
try{ 0'V5/W
if(ps!=null) { )2V:
ps.clearParameters(); ^HV>`Pjd}=
ps.close(); (eCJ;%%k
ps=null; }`W){]{kO
} J6U$qi
}catch(SQLException e){} *+j*{>E
DBUtils.closeConnection(conn); @x"0_Qw
} LV\DBDM
} G B>QK
public long getLast(){ M,/mE~
return lastExecuteTime; o*DN4oa)
} r G4';V^q
public void run(){ MS\>DW
long now = System.currentTimeMillis(); :uWw8`
if ((now - lastExecuteTime) > executeSep) { l^|UCgRn
//System.out.print("lastExecuteTime:"+lastExecuteTime); Sz^
veh?
//System.out.print(" now:"+now+"\n"); @\|_
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); R_sr?V|"
lastExecuteTime=now; 6^]!gR#B
executeUpdate(); E"+QJ~!
} 3pv4B:0
else{ O-LO/*5MI
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^Wc@oa`
}
0Uo\wyd
} J4Nln
} AtdlZ
//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 2] zq#6ix
A D1=[I3
类写好了,下面是在JSP中如下调用。 ( M7pT
x|mqL-Q f
<% <_3b1VhZ
CountBean cb=new CountBean(); |&FkksNAl\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); wQe_vY
CountCache.add(cb); Pa~)"u8
out.print(CountCache.list.size()+"<br>"); ~(Q)"s\1I
CountControl c=new CountControl(); :^kZ.6Q@
c.run(); ^r*r
w=
out.print(CountCache.list.size()+"<br>"); +)y^'Qs
%>