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: Q2L>P<87T
&O:IRR7p
CountBean.java m/T3Um
'kC,pN{->
/* ,_N+t:*#0
* CountData.java hN5?u:
* wIbxnn
* Created on 2007年1月1日, 下午4:44 Q/[g|"
* '=Z]mi/aw
* To change this template, choose Tools | Options and locate the template under UCz\SZ{za
* the Source Creation and Management node. Right-click the template and choose fK %${
* Open. You can then make changes to the template in the Source Editor. <U]!1
*/ 6Kbc:wlR
$Sx(vq6(
package com.tot.count; >OLKaghV.5
{#_CzI.0f
/** `Q@w*ta)
* g"dq;H
* @author 4*D'zJsJ
*/ U{JD\G8m
public class CountBean { S#{jyU9 ]
private String countType; 3tjF4C>h|
int countId; vR)f'+_Nz
/** Creates a new instance of CountData */ l:i&l?>_
public CountBean() {} (qbL=R"
public void setCountType(String countTypes){ 2YbI."ob
this.countType=countTypes; (\8~W*ej"
} Q:5^K
public void setCountId(int countIds){
mdtG W
this.countId=countIds; 6${=N}3Kw
} ;J>upI
public String getCountType(){ Pss$[ %
return countType; x@)G@'vV|
} 'nMj<:0wlD
public int getCountId(){ =.48^$LWx
return countId; 7G\a5
}
@BmI1
} 3T= ?!|e
]J(BaX4
CountCache.java j%`%
DQ
Ym8
V)
/* D^Gs_z$['
* CountCache.java */6lyODf
* euyd(y$'k
* Created on 2007年1月1日, 下午5:01 yp!7^
* i<b-$9
* To change this template, choose Tools | Options and locate the template under hjgB[
&U>
* the Source Creation and Management node. Right-click the template and choose _yRD*2 !;
* Open. You can then make changes to the template in the Source Editor. ;Zy[2M
*/ lS96Z3k"SB
}WV}in0
package com.tot.count; Z_h-5VU-
import java.util.*; xjy(f~'
/** kj>!&W57
* X=KC+1e
* @author 2;w`W58
*/ j>`-BN_
public class CountCache { 4Jf9N'
public static LinkedList list=new LinkedList(); %#<MCiaK
/** Creates a new instance of CountCache */ KK}ox%j
public CountCache() {} |E9'ii&?B
public static void add(CountBean cb){ (2ZkfN
if(cb!=null){ &\y`9QpVF
list.add(cb); 8Drz
i!}
} ictV7)
} RG.wu6Av
} .>a
[
1{AK=H')
CountControl.java 4Ql9VM%y
VTa%
/* t$e' [;w
* CountThread.java FyQr$;r
* 7Fx0#cS"\
* Created on 2007年1月1日, 下午4:57 1Ror1%Q"?
* v`@NwH<r
* To change this template, choose Tools | Options and locate the template under mxE<
* the Source Creation and Management node. Right-click the template and choose 2FcNzAaV
* Open. You can then make changes to the template in the Source Editor. `W:z#uNG]
*/ +BVY9U?\"
dmWCNeja.
package com.tot.count; L54]l^ls>
import tot.db.DBUtils; nb.|^O?
import java.sql.*; oOHY+'V
/** [MuZ^'dR
* ^=k=;
* @author 8iTB
*/ nV`U{}x
public class CountControl{ \zcR75
private static long lastExecuteTime=0;//上次更新时间 _X|prIOb=
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6e8 gFQ"w2
/** Creates a new instance of CountThread */ S=gby
public CountControl() {} ^
L]e]<h(
public synchronized void executeUpdate(){ e#)NYcr6
Connection conn=null; $A`m8?bY
PreparedStatement ps=null; fD lo L
try{ S:XsO9:{
conn = DBUtils.getConnection(); Cs(sar:7
conn.setAutoCommit(false); ?;y-skh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); nEUUD3a
for(int i=0;i<CountCache.list.size();i++){ 'J$@~P
CountBean cb=(CountBean)CountCache.list.getFirst(); O}w%$ mq
CountCache.list.removeFirst(); 9a @rsyX
ps.setInt(1, cb.getCountId()); ;{aGEOP'U
ps.executeUpdate();⑴ yM `u]p1
//ps.addBatch();⑵ )3)7zulnXH
} J?dLI_{<
//int [] counts = ps.executeBatch();⑶ :w-:B^VB
conn.commit(); 'zbvg0 T
}catch(Exception e){ Z+u.LXc|c
e.printStackTrace(); ;*$e8y2
} finally{ 1yZA_x15:
try{ JEk'2Htx
if(ps!=null) { [_nOo `
ps.clearParameters(); Rpv[rvK'
ps.close(); $btu=_|f
ps=null; -pIz-*
} haY]gmC
}catch(SQLException e){} .$H"j>
DBUtils.closeConnection(conn); ^86M94k
} x+j@YWDpG"
} eZ+6U`^t
public long getLast(){ [@ev%x,
return lastExecuteTime; tfN[-3)Z
} k#zDY*kj
public void run(){ :dh; @kp
long now = System.currentTimeMillis(); e`S\-t?Z
if ((now - lastExecuteTime) > executeSep) { MqB@}!
//System.out.print("lastExecuteTime:"+lastExecuteTime); *g,ls(r\[
//System.out.print(" now:"+now+"\n"); rVqQo`K\
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); jLVG=rOn
lastExecuteTime=now; |$b8(g$s)
executeUpdate(); FGx)?
} 4"k &9+>
else{ GTM0Qvf?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4U\}"Mk
} g{Al:}u>
} D>[Sib/@
} DH
yv^
//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 VaY#_80$s
**L&I5Hhm
类写好了,下面是在JSP中如下调用。 mpug#i6q
ewU*5|*[
<% jel:oy|_
CountBean cb=new CountBean(); m~5 unB9
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Cd_@<
CountCache.add(cb); Ai1"UYk\\Y
out.print(CountCache.list.size()+"<br>"); J<;io!
CountControl c=new CountControl(); &J&'J~N
c.run(); hNM8H
out.print(CountCache.list.size()+"<br>"); 6qHD&bv\%C
%>