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: 2g-` ]Vqb
b5a.go
CountBean.java rD
&D)w
F<|t\KOW
/* B^v8,;jZT
* CountData.java 8sOQ9
* f&KdlpxKv
* Created on 2007年1月1日, 下午4:44 ~h$wH{-U#
* -ijC_`>
* To change this template, choose Tools | Options and locate the template under vXE0%QE'Q
* the Source Creation and Management node. Right-click the template and choose &,:h)
* Open. You can then make changes to the template in the Source Editor. `A@w7J'
*/ w@-M{?R
j;0vAf
package com.tot.count; G`0V)S
'b&yrBFD
/** zM#sOg
* H t(n%;<
* @author j5$GFi\kB
*/ P-`(0M7^
public class CountBean {
9+=gke
private String countType; $IQw=w7p
int countId; % Zjdl
/** Creates a new instance of CountData */ <0P5 o|
public CountBean() {} 8\.b4FNJ
public void setCountType(String countTypes){ }UwO<#
this.countType=countTypes; tc+WWDP#"
} (p#0)C
public void setCountId(int countIds){ pCi#9=?N
this.countId=countIds; dT"hNHaf
} p4!:]0c
public String getCountType(){ #W>QY Tp
return countType; <AH1i@4
} +Vb8f["+-
public int getCountId(){ ^D%Za'
return countId; X{xBYZv4
} #%0Bx3uM
} W~1~k{A
}_9,w;M$
CountCache.java "R>FqX6FB
CusF/>
/* :aCrX
* CountCache.java o\b- _E5"?
* 2_^aw[-
* Created on 2007年1月1日, 下午5:01 w
obgu
* MK#wut
* To change this template, choose Tools | Options and locate the template under V~G`kkNy
* the Source Creation and Management node. Right-click the template and choose ED>prE0
* Open. You can then make changes to the template in the Source Editor. tJViA`@x
*/ i:]*P
"*1f;+\
package com.tot.count; "hxN !,DEZ
import java.util.*; HBS\<}
/** 4`m~FNVS
* G2bDf-1ew
* @author N["W Ir
*/ nAIo{
F
public class CountCache { *g}Yw
public static LinkedList list=new LinkedList(); Hb} X-6N
/** Creates a new instance of CountCache */ H %JaZ?(
public CountCache() {} K.<.cJE
public static void add(CountBean cb){ i9<pqQ
if(cb!=null){ ygJr=_iA9
list.add(cb); JxE53ev
} i':ydDOOHA
} fWfk[(M'9
} XR2~Q)@
TxjYrzC
CountControl.java nRL. ppUI
6tHO!`}1
/* M5nWVK7c
* CountThread.java )c n+1R
* Qd}m`YW-f$
* Created on 2007年1月1日, 下午4:57 )a9 ]US^
* >(uZtYM\j
* To change this template, choose Tools | Options and locate the template under d@`M
CchCB
* the Source Creation and Management node. Right-click the template and choose JWvjWY2+P
* Open. You can then make changes to the template in the Source Editor. x3jb%`o#!
*/ %VYAd)gC
[[PEa-992
package com.tot.count; poGc a1
import tot.db.DBUtils; IG)s^bP
import java.sql.*; ;c~cet4
/** zJP6F.Ov!
* @k[R/,#'[t
* @author F<>!kK/c
*/ EVp,Q"V]
public class CountControl{ 3bk|<7tl
private static long lastExecuteTime=0;//上次更新时间 )[0T16
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 f` =CpO*
/** Creates a new instance of CountThread */ @KX
\Er
public CountControl() {} (" LQll9
public synchronized void executeUpdate(){ kt`nbm|aw
Connection conn=null; ];.pK
PreparedStatement ps=null; '!l1=cZD
try{ 4wC+S9I#E^
conn = DBUtils.getConnection(); d
;vT ~;
conn.setAutoCommit(false); 6"Bic rY
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $o$
maA0
for(int i=0;i<CountCache.list.size();i++){ ~ P~
CountBean cb=(CountBean)CountCache.list.getFirst(); M@ed>.
CountCache.list.removeFirst();
;};wq&b#
ps.setInt(1, cb.getCountId()); ^O^l(e!3
ps.executeUpdate();⑴ lY|Jr{+Ln
//ps.addBatch();⑵ U2uF&6v
} }*.0N;;C
//int [] counts = ps.executeBatch();⑶ *K> l*l(f]
conn.commit(); xX*H7#
}catch(Exception e){ wP[t0/dl
e.printStackTrace(); fP.F`V_Y
} finally{ XGP6L 0j
try{ 'cY` w
if(ps!=null) { j'9"cE5_
ps.clearParameters(); i4^o59}8
ps.close(); TXe$<4"
ps=null; XsnF~)YW
} foJdu+^
}catch(SQLException e){} :0s]U_h
DBUtils.closeConnection(conn); 626Z5Afg
} ^Z~;4il_F
} A.hd
Kl
public long getLast(){ 1V8-^
return lastExecuteTime; v) vkn/:
} h/~n\0,J/
public void run(){ pdE3r$C
long now = System.currentTimeMillis(); ?LvCR_D:
if ((now - lastExecuteTime) > executeSep) { zZVfj:i8
//System.out.print("lastExecuteTime:"+lastExecuteTime); z dO#0tN
//System.out.print(" now:"+now+"\n"); p.LFVFPT
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); v\p;SwI
lastExecuteTime=now; \Y"Wu
executeUpdate(); 2WU@*%sk"
} m1Y>Nj[f
else{ ~gGZmTb
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4:U?u
} BJ% eZ.
} _YF%V;X
} `FoxP
//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 7Hm3;P.
^tXJj:wtS
类写好了,下面是在JSP中如下调用。 ]c! ;L5
.A6(D$O k
<% Q+YRf3$
CountBean cb=new CountBean(); 7b<yVP;{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ULQMG'P^D
CountCache.add(cb); hWX% 66
out.print(CountCache.list.size()+"<br>"); )B[0JrcE
CountControl c=new CountControl(); HD(.BW7
c.run(); ;[fw]P n
out.print(CountCache.list.size()+"<br>"); s`0QA!G{-
%>