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: 3uCC_Am
\pB"R$YZ6
CountBean.java ?'p`Qv
mCe,(/>l+
/* )'xTDi
* CountData.java _d&zHlc_
* 59O;`y0
* Created on 2007年1月1日, 下午4:44 b5
YE4h8%
* "g\
* To change this template, choose Tools | Options and locate the template under J[;c}
* the Source Creation and Management node. Right-click the template and choose FGBPhH% (8
* Open. You can then make changes to the template in the Source Editor. gk~.u
*/ V^=z\wBZ
ts3%cRN r
package com.tot.count; 5UR$Pn2a2
JQ'NFl9<
/** dfGdY"&
* ZPn`.Qc
* @author ]v@#3,BV
*/ x&tad+T
public class CountBean { ZrnZ7,!@
private String countType; eb2~$ ,$
int countId; m,$oV?y>j
/** Creates a new instance of CountData */ IP$^)t[
public CountBean() {} BD[XP`[{
public void setCountType(String countTypes){ (1fE^KF@f
this.countType=countTypes; G5E03xvL
} (1%u`#5n-N
public void setCountId(int countIds){ /sH3Rk.>
this.countId=countIds; &@c=$+#C
} p-UACMN&c
public String getCountType(){ W+&ZYN'E
return countType; Vp\BNq_!s
} =U!'v X d
public int getCountId(){ CN\SxK`,
return countId; xZjD(e'
} |Rw0$he
} C
7YZ;{t
b4!(~"b.
CountCache.java ?C//UN;
||cG/I&,
/* P*T'R
* CountCache.java Q1IN@Db}y
* 6 DD^h:*>
* Created on 2007年1月1日, 下午5:01 2BBGJE
* <g5Btwo%
* To change this template, choose Tools | Options and locate the template under u }D.yI8
* the Source Creation and Management node. Right-click the template and choose zFqH)/
* Open. You can then make changes to the template in the Source Editor. 3zp)!QJi
*/ Y<X%'Wd\
xvQJTRk
package com.tot.count; 1j# ~:=I
import java.util.*; RtGETiA\b
/** l.\Fr+*ej
* CtV$lXxup
* @author uz".!K[,wE
*/ RD_&m?d
public class CountCache { cPi 3UjY~
public static LinkedList list=new LinkedList(); Z$kff-Y4
/** Creates a new instance of CountCache */ =|bM|8,
public CountCache() {} Y2!OJuyGc
public static void add(CountBean cb){ U")~bU
if(cb!=null){ mQtGE[
list.add(cb); ~;QO`I=0P
} &OK(6o2m;
} E< "aUnI
}
1Wtr_A
t8\F7F P
CountControl.java VZ'[\3J
]
NL-)8u
/* 9xyj,;P>
* CountThread.java _N$3c<dY'
* ;RB]awE
* Created on 2007年1月1日, 下午4:57 z*>"I
*
@D^y<7(
* To change this template, choose Tools | Options and locate the template under 6A;V[3
* the Source Creation and Management node. Right-click the template and choose %RG kXOgp
* Open. You can then make changes to the template in the Source Editor. D' ZR>@w@
*/ zJ93EtlF
WW\u}z.QJ
package com.tot.count; !fZ\GOx
import tot.db.DBUtils; G`9Ud
import java.sql.*; d^mw&F)S
/** |)* K#%j
* 5'd$TC
* @author Q4Zuz)r*
*/ rE;*MqYt&
public class CountControl{ *%7 [{Loz
private static long lastExecuteTime=0;//上次更新时间 O
$'#8
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >N62t9Ll[
/** Creates a new instance of CountThread */ %B}Q .'
public CountControl() {} s]50Y-C
public synchronized void executeUpdate(){ {mrTpw
Connection conn=null; 6X~.J4
PreparedStatement ps=null; Ci4`,
try{ }pdn-#
conn = DBUtils.getConnection(); ExeD3Zj
conn.setAutoCommit(false); JS<S?j?*/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); SE.r 'J0
for(int i=0;i<CountCache.list.size();i++){ 0_q8t!<xJw
CountBean cb=(CountBean)CountCache.list.getFirst(); E;/WP!/.
CountCache.list.removeFirst(); ;{EIx*<d
ps.setInt(1, cb.getCountId()); =5/ow!u8
ps.executeUpdate();⑴ Xyy;BO:
//ps.addBatch();⑵ kd)Q$RA(
} a$r-
U_?
//int [] counts = ps.executeBatch();⑶ gI "ZhYI
conn.commit(); pYf57u
}catch(Exception e){ g5M=$y/H
e.printStackTrace(); k#uSH
eq7f
} finally{ nNz1gV:0X
try{ `)%z k W
if(ps!=null) { _QBN/KE9
ps.clearParameters(); ?!^ow5"8
ps.close(); O2;FaASF
ps=null; fb-Lp#!T39
} i)y8MlC{
}catch(SQLException e){} 1/+d@s#t
DBUtils.closeConnection(conn); w\,N}'G
} LvtHWt
} uP, iGA
public long getLast(){ (VDY]Q)
return lastExecuteTime; lC/1,Z/M
} 60,z! Vv
public void run(){ )Tjh
long now = System.currentTimeMillis(); /By:S/[1pL
if ((now - lastExecuteTime) > executeSep) { Z,zkm{9*
//System.out.print("lastExecuteTime:"+lastExecuteTime); zU7co.G
//System.out.print(" now:"+now+"\n"); EyR~VKbJ'
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); K&ZN!VN/p
lastExecuteTime=now; %O6r
executeUpdate(); TOapq9B]
} p3r("\Za,
else{ Y`F) UwKK
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); z^lcc7
} q9Zp8&<EqH
}
_U.|$pU
} /]j^a:#"6t
//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 ~,ZU+
P.bxq50
类写好了,下面是在JSP中如下调用。 JLd-{}A""-
e}dGK=`
<% ,w`g+ 9v
CountBean cb=new CountBean(); >~@O\n-t
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $7h]A$$Fv
CountCache.add(cb); "&Hr)yyWG
out.print(CountCache.list.size()+"<br>"); a-e_ q
CountControl c=new CountControl(); "I)/|x\G*
c.run(); V>Dqw!
out.print(CountCache.list.size()+"<br>"); ^h\(j*/#X
%>