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: uuj"Er31
*F:]mgg
CountBean.java Y^LFJB|b4
8DTk<5mW~
/* 1W~-C B>
* CountData.java v,vTRrpK
* 0!=e1_
* Created on 2007年1月1日, 下午4:44 3sGrX"0D
* OdQ>h$ gZ
* To change this template, choose Tools | Options and locate the template under el!Bi>b9c!
* the Source Creation and Management node. Right-click the template and choose WAY<X:|We
* Open. You can then make changes to the template in the Source Editor. &ukNzV}VW
*/ 4W9!_:j(j
*p?b "{_a
package com.tot.count; qh$D;t1=
7qE V5!
/** qNHS 1
* w GZ(bKyO
* @author *"
<tFQ
*/ {N5g52MN
public class CountBean { 7~\Dzcfk"P
private String countType; 4:r^6m%%
int countId; :&yRvu
/** Creates a new instance of CountData */ \!ESmxSa;
public CountBean() {} y NV$IN%
public void setCountType(String countTypes){ PL~k
`L
this.countType=countTypes; _WK+BxH
} QZ{&7mc>
public void setCountId(int countIds){ e::5|6x
this.countId=countIds; hPr
} iN<5[ztd
public String getCountType(){ 6?*iIA$b
return countType; ]p'Qk
} n!Y.?mU6
public int getCountId(){ ("/*k
return countId; $O}gl Q
} 1\YX|
} Ccz:NpK+
';aPoaO %
CountCache.java x(}t r27o
p5F[( H|9
/* ^%_B'X9
* CountCache.java /<:9NP'^
* ;x^&@G8W`
* Created on 2007年1月1日, 下午5:01 1bzPBi
* ;ok];4`a
* To change this template, choose Tools | Options and locate the template under jLr8?Hyf
* the Source Creation and Management node. Right-click the template and choose 4L!{U@'
* Open. You can then make changes to the template in the Source Editor. q4Ye
*/ |<y[gj4`T/
DDAqgx
package com.tot.count; $#R.+B
import java.util.*; ([f6\Pw\ <
/** x?CjRvT$
* uzp!Y&C
* @author Va=0R
*/ AN:,t(w
public class CountCache { 83R"!w18
public static LinkedList list=new LinkedList(); @Jvw"=
/** Creates a new instance of CountCache */ QQ2xNNF[
public CountCache() {} ^|\ *i
public static void add(CountBean cb){ Dj!J 4uD
if(cb!=null){ YY7:WQS
list.add(cb); \!cqeg*53
} ,6t0w|@-k
} aF'Ik XG d
} *otJtEI>6
Yf {s0Z
CountControl.java u x:,io
S<p
"k]
/* CWBsiL
f
* CountThread.java ,}{E+e5jh7
* ?'T>/<(
* Created on 2007年1月1日, 下午4:57 $Fr2oSTT)
* M8juab%y
* To change this template, choose Tools | Options and locate the template under rcI(6P<*
* the Source Creation and Management node. Right-click the template and choose g<,v2A
* Open. You can then make changes to the template in the Source Editor. Eq.c;3
*/ 1Za\T?V
?5B}ZMW
package com.tot.count; AO']Kmm
import tot.db.DBUtils; a*SJHBB
import java.sql.*; qsJA|z&6x
/** QJ"Bd`wc
* vpXS!o>/Sn
* @author 2YwV}
*/
5j]}/Aq
public class CountControl{ dDpe$N
private static long lastExecuteTime=0;//上次更新时间 N#,4BU
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ORtl~V'
/** Creates a new instance of CountThread */ |qI_9#M\(
public CountControl() {} uL-i>!"L!}
public synchronized void executeUpdate(){ =,T~F3pK
Connection conn=null; + !_^MB kk
PreparedStatement ps=null; ;U20g:K
try{ !5A
nr
conn = DBUtils.getConnection(); W{-N,?z
conn.setAutoCommit(false); 9MHb<~F
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ny=CtU!z
for(int i=0;i<CountCache.list.size();i++){ :nwcO3~`
CountBean cb=(CountBean)CountCache.list.getFirst(); G uDus2#+
CountCache.list.removeFirst(); }1_gemlf
ps.setInt(1, cb.getCountId()); Wb4sfP_
ps.executeUpdate();⑴ >Y2Rr9
//ps.addBatch();⑵ /AMtT%91
} PKjA@+
//int [] counts = ps.executeBatch();⑶ iicrRGp3
conn.commit(); ie$=3nZJ}
}catch(Exception e){ ~!:F'}bj
e.printStackTrace(); ahV_4;yF
} finally{ (b{
{B$O
try{ #e9B|Y?b
if(ps!=null) { ,%KB\;1mn'
ps.clearParameters(); (j-(fS
ps.close(); |xf%1(Rl@
ps=null; t S!~>X
} %<
W1y
}catch(SQLException e){} " g_\W
DBUtils.closeConnection(conn); ]AHUo;(f%
} J| 'T2g
} <c\aZ9+V
public long getLast(){ B]Zsn`n
return lastExecuteTime; ,#c-"xY
} ^
1J;SO|
public void run(){ 7PisX!c,h
long now = System.currentTimeMillis(); C&5T;=<jKO
if ((now - lastExecuteTime) > executeSep) { y!v $5wi
//System.out.print("lastExecuteTime:"+lastExecuteTime); gH_r'j
//System.out.print(" now:"+now+"\n"); +- .BF"}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1%-?e``.
lastExecuteTime=now; _aDx('
executeUpdate(); <4O=[Q 5S
} Lqch~@E&%#
else{ .
}=;]=
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 3)3'-wu
} X,OxvmDm
} _X]?
} X`aED\#\h
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 .7kVC
aoJ&< vl3
类写好了,下面是在JSP中如下调用。 {;-$;\D
RMvlA'c
<% 8wy"m=>=b}
CountBean cb=new CountBean(); ]7VK&YfN
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /S;?M\
CountCache.add(cb); =Wjm_Rvk9
out.print(CountCache.list.size()+"<br>"); >yWJk9hf
CountControl c=new CountControl(); P0z "Eq0S
c.run(); bu hxC5i%
out.print(CountCache.list.size()+"<br>"); ]Ny]Ox<
%>