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: {3!E8~
cV:Ak~PKl
CountBean.java ;"|QW?>$D
()e|BFL .
/* 'wni.E&
* CountData.java -_ <z_IL\%
* y3OF+;E
* Created on 2007年1月1日, 下午4:44 }56WAP}Z 4
* T,h9xl9i
* To change this template, choose Tools | Options and locate the template under n}/4em?
* the Source Creation and Management node. Right-click the template and choose d
r$E:kr
* Open. You can then make changes to the template in the Source Editor. I&;9
*/ q5{h@}|M
SM\qd4
package com.tot.count; lRR A2Kql
{A'_5 X9
/** nt8&Mf
* '^M.;Giz
* @author {r'+icvLX
*/ F}?4h Dt
public class CountBean { b_^y
Ke^W
private String countType; i!)\m0Wm
int countId; @MO/LvD
/** Creates a new instance of CountData */ 8QMib3p
public CountBean() {} 9e Fj+
public void setCountType(String countTypes){ 5bBCI\&sam
this.countType=countTypes; 1>Q4&1Vn
} rFaG-R
public void setCountId(int countIds){ \/ipYc
this.countId=countIds; )Z)Gb~G
} " =6kH,
public String getCountType(){ }=Ul8
<
return countType; (eSsx/
} QJ!2Vw4K
public int getCountId(){ }(7TiCwd
return countId; <~P!yL r
} w[C*w\A\M
} U7Oa
13Qz
DLuaM?7
CountCache.java m`}mbm^
iBI->xU[U
/* -Aojk8tc
* CountCache.java #nw+U+qL
* "c\WZB`|
* Created on 2007年1月1日, 下午5:01 %%NT m
* -E~r?\;X
* To change this template, choose Tools | Options and locate the template under 83 <CDjD
* the Source Creation and Management node. Right-click the template and choose RLZfXXMn
* Open. You can then make changes to the template in the Source Editor. x"!`JDsS
*/ @dx8 {oQ
4}s'xMT!
package com.tot.count; Up6OCF
import java.util.*; x-]:g&5T
/** i&?\Pp;5-j
* (cyvE}g
* @author z%#-2&i
*/ AUu<@4R7
public class CountCache { XwFTAaZ
public static LinkedList list=new LinkedList(); &,yF{9$G
/** Creates a new instance of CountCache */ (Ldvx_
public CountCache() {} e ^oGiL~
public static void add(CountBean cb){ S~)`{
\
if(cb!=null){ ;|0P\3
list.add(cb); ?|98Y"w
} /
g{8
} ^RO<r}Bu
} 1y\bJ
g?Tev^D
CountControl.java `a83bF35
0|.jIix;
/* TY'c'u,
* CountThread.java L9N}lH
* Ar[|M2|
* Created on 2007年1月1日, 下午4:57 U[02$gd0l
* Vjs'|%P7
* To change this template, choose Tools | Options and locate the template under URs]S~tk
* the Source Creation and Management node. Right-click the template and choose K4jHha
* Open. You can then make changes to the template in the Source Editor. tjt^R$[ @
*/ Le:C8^
WG3!M/4r H
package com.tot.count;
EQ ee5}
import tot.db.DBUtils; }8"
|q3k
import java.sql.*; 5a'`%b{{
/** ]XbMqHGS
* jLM([t
* @author &3Yj2Fw
*/ =PciLh
public class CountControl{ >mX6;6FF
private static long lastExecuteTime=0;//上次更新时间 )v_v 7 ~H&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 nq HpYb6I0
/** Creates a new instance of CountThread */ !p).3Kx0
public CountControl() {} Rx&O}>"E>l
public synchronized void executeUpdate(){ NIVR;gm
Connection conn=null; z?.9)T9_
PreparedStatement ps=null; \fUX_0k9,
try{ bsDA&~)s
conn = DBUtils.getConnection(); g i6s+2
conn.setAutoCommit(false); #Zw:&'
QB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); JJ7A`
;
for(int i=0;i<CountCache.list.size();i++){ x<M::")5!V
CountBean cb=(CountBean)CountCache.list.getFirst(); n)"JMzjQ<
CountCache.list.removeFirst(); QMz =e
ps.setInt(1, cb.getCountId()); o+&Om~W
ps.executeUpdate();⑴ R|$AcNp
//ps.addBatch();⑵ G@#lf@M]
} Rlk3AWl2u
//int [] counts = ps.executeBatch();⑶ Y4HN1
conn.commit(); 6" * <0
}catch(Exception e){ Lo1ySLo$G
e.printStackTrace(); i7-~"g
} finally{ Ajm!;LA[jO
try{ lQ`=PFh
if(ps!=null) { dh7`eAMY
ps.clearParameters(); (Fon!_$:
ps.close(); zP%s] >hH
ps=null; k\.9iI'6
} 'Og@<~/Xy
}catch(SQLException e){} 3\@2!:>
DBUtils.closeConnection(conn); rhbz|Uq
} nK :YbLdK,
} v,ZYh w
public long getLast(){ H5x7)1Ir|
return lastExecuteTime; +FqD.= 8
} &|{1Ws
public void run(){ B223W_0"o
long now = System.currentTimeMillis(); xyL)'C
if ((now - lastExecuteTime) > executeSep) { 7-K8u
//System.out.print("lastExecuteTime:"+lastExecuteTime); |-}.Y(y
//System.out.print(" now:"+now+"\n"); * )<+u~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); |T""v_q
lastExecuteTime=now; q7Hf7^a
executeUpdate(); t<Yi!6
} }w$2,r
gA
else{ aYaEy(m
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Gy/w #4xj
} =|z:wlOs
} vd[7Pxe
} \t7yH]:>@
//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 ^qR|lA@=\
'-%1ILK$3r
类写好了,下面是在JSP中如下调用。 }4Yz P 4
7yfh4-1M
<% m}wn+R
CountBean cb=new CountBean(); !{.CGpS ]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); nU>P%|loXx
CountCache.add(cb); ae sk.
out.print(CountCache.list.size()+"<br>"); gQ{ #C'
CountControl c=new CountControl(); '%rT]u3U
c.run(); tdH[e0x B
out.print(CountCache.list.size()+"<br>"); {h+8^
%>