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: ~SQxFAto
h7"U1'b
CountBean.java $q@d.Z>;
7amVnR1f
/* |cma7q}p
* CountData.java OY`B{jV-
* KN|<yF
* Created on 2007年1月1日, 下午4:44 }<A.zwB<i
* Cr7Zi>sd<!
* To change this template, choose Tools | Options and locate the template under )Wk_|zO-
* the Source Creation and Management node. Right-click the template and choose tr,W)5O@L
* Open. You can then make changes to the template in the Source Editor. (4R(5t
*/ Q p>b
A%.mIc.
package com.tot.count; l}z<q
Dd5
9xNKm
/** 4$&l`yWU+
* >5~#BrpwG
* @author nL:&G'd
*/ ZiJF.(JS
public class CountBean { C!5A,| DX
private String countType; 8~o']B;lJ
int countId; :'Qiwf&
/** Creates a new instance of CountData */ `sYFQ+D#O
public CountBean() {} M@A3+v%K
public void setCountType(String countTypes){ F$?Ab\#B
this.countType=countTypes; ;yt6Yp.6e
} ?N<My&E
public void setCountId(int countIds){ ;9T}h2^`B
this.countId=countIds; %f1%9YH
} >s{I@#9
public String getCountType(){ D9oNYF-V
return countType; tbRW6
} V|MGG
public int getCountId(){ |qUGB.Q
return countId; J;0;oXwJ<
} ~ 1h#
} :*''ci
yXR1NYg
CountCache.java `Y?VQ~ci>
K.)!qkW-%S
/* n(F!t,S1i
* CountCache.java r.H`3m.0q
* )r9 9zdUk
* Created on 2007年1月1日, 下午5:01 2^WJ1: A
* d+JK")$9C
* To change this template, choose Tools | Options and locate the template under o]e,5]
* the Source Creation and Management node. Right-click the template and choose 'cs(gc0
* Open. You can then make changes to the template in the Source Editor. ii)#(b:V
*/ 15g!Q
*v
,&t+D-s<f
package com.tot.count; te+} j7SU
import java.util.*; V,&%[H [
/** "<ZV'z
* 9* )&hhBs,
* @author dEoIVy _9R
*/ c|Ivet>3
public class CountCache { X8|H5Y:
public static LinkedList list=new LinkedList(); pr0X7 #_E5
/** Creates a new instance of CountCache */ .{1$;K @
public CountCache() {} <,]:jgX
public static void add(CountBean cb){ JtL>mH
if(cb!=null){ t}q
e_c
list.add(cb); Js,! G
} p27Dcwov
} )O1]|r7v
} Xsq@E#@S
*'/,
CountControl.java 0WUBj:@g
k)p`x"To
/* B@,r8)D
* CountThread.java ?*fa5=ql
* Ww]$zd-bo
* Created on 2007年1月1日, 下午4:57 ;'"'|} xn
* $p0nq&4c
* To change this template, choose Tools | Options and locate the template under AWR :~{
* the Source Creation and Management node. Right-click the template and choose 2}vibDq p
* Open. You can then make changes to the template in the Source Editor. tDK@?PfKz
*/ Q]k<Y
B5lwQp]
package com.tot.count; +Iyyk02V
import tot.db.DBUtils; r6DLShP-Ur
import java.sql.*; j_8 Y Fz5
/** MKHnA|uQ](
* \<LCp;- K
* @author 9p{4-]
*/ #t+?eye~
public class CountControl{ :5t4KcQ
private static long lastExecuteTime=0;//上次更新时间 #I/P9)4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Qa{5]+E
/** Creates a new instance of CountThread */ VdHT3r
public CountControl() {} jRK}H*uem
public synchronized void executeUpdate(){ Y <6|z3
Connection conn=null; R|st<P
PreparedStatement ps=null; 0@ `]m
try{ #"gt&t9Q
conn = DBUtils.getConnection(); 8Y`Lq$u
conn.setAutoCommit(false); F\:~^`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); |a(KVo
for(int i=0;i<CountCache.list.size();i++){ VeA@HC`?"
CountBean cb=(CountBean)CountCache.list.getFirst(); ^)AECn
CountCache.list.removeFirst(); V*p[6{U0
ps.setInt(1, cb.getCountId()); -$d?e%}#
ps.executeUpdate();⑴ h,{m{Xh
//ps.addBatch();⑵ RHF"$6EAFG
} b;i*}4h!
//int [] counts = ps.executeBatch();⑶ jBLTEb
conn.commit(); :@L7RZ`_
}catch(Exception e){ 72<9xNcB!}
e.printStackTrace(); x5lVb$!G
} finally{ Fy=GU<&AI
try{ 3q]0gU&??
if(ps!=null) { VE\L&d2S
ps.clearParameters(); ^{Y, `F
ps.close(); eD>b|U=/
ps=null; +b|F_
} k6tCfq;
}catch(SQLException e){} =M\yh,s!
DBUtils.closeConnection(conn); Rh'z;Gyr
} >q}3#TvP@
} >F$9&s&
public long getLast(){ QQJGqM3a2
return lastExecuteTime; s9?mX@>h
} X`8<;l
public void run(){ A(y6]E!
long now = System.currentTimeMillis(); 1-kuK<KR
if ((now - lastExecuteTime) > executeSep) { V3,C5KKk&z
//System.out.print("lastExecuteTime:"+lastExecuteTime); N63?4'_W
//System.out.print(" now:"+now+"\n"); Ia2WBs=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); e{)giJY9
lastExecuteTime=now; Rk$7jZdTf
executeUpdate();
|~9rak,
} M
Kyj<@[
else{ jFSR+mP!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]cRvdUGv
} zEQ]5>mG
} iJ>=!Q
} +t7HlAXB#
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 g\aO::
RoqkT|#$
类写好了,下面是在JSP中如下调用。 $Itmm/M
"*lx9bvV_
<% ZU\$x<,
CountBean cb=new CountBean(); JsY,Q,D q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Ws2q/[\oz
CountCache.add(cb); 7[Us.V@
out.print(CountCache.list.size()+"<br>"); 6i/unwe!`)
CountControl c=new CountControl(); bb_elmb)n
c.run(); [v1$Lp
out.print(CountCache.list.size()+"<br>"); z~H1f$}
%>