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: FZ8Qj8
wp:Zur5Y
CountBean.java u{l4O1k/c
UCTc$3
/* 1$m{)Io2(
* CountData.java 2)
2:KX
* c<Q*g
* Created on 2007年1月1日, 下午4:44 "`Xbi/i
* YNp-A.o
W@
* To change this template, choose Tools | Options and locate the template under Ou
f \%E<
* the Source Creation and Management node. Right-click the template and choose cnG>EG
* Open. You can then make changes to the template in the Source Editor. 8N<mV^|}
*/ $!\L6;:
n+vv
%
package com.tot.count; 5fmQ+2AC1
?PV@WrU>B
/** $8[JL\
* "`a,/h'
* @author )$*B
*/ vP%:\u:{
public class CountBean { #9qX:*>h
private String countType; z>
N73 u
int countId; 2Z`Jr/
/** Creates a new instance of CountData */ P4E_<v[
public CountBean() {} Pt6d5EIG
public void setCountType(String countTypes){ _,p/2m-Pj
this.countType=countTypes; : 'pK
} W(.svJUgb.
public void setCountId(int countIds){ dLR[<@E
this.countId=countIds; FL0yRF5
} rK'O 85)eU
public String getCountType(){ ("<4Ry.u
return countType; Fa #5a'}I
} $lUz!mjG
public int getCountId(){ #wh[F"zX
return countId; a5w E{K
} kpQN>XV#
} OE}c$!@
,wyEo>>4)
CountCache.java wDBU+Z
D<*)^^
/* Q7mikg=1-
* CountCache.java ZA'0q
* -KqMSf&9
* Created on 2007年1月1日, 下午5:01 'loko#6
* /c7jL4oD
* To change this template, choose Tools | Options and locate the template under (^<skx>
* the Source Creation and Management node. Right-click the template and choose =#&+w[4?&.
* Open. You can then make changes to the template in the Source Editor. N)KN!!
*/ kn&BGYt
N[yS heT
package com.tot.count; 9h6siK(F
import java.util.*; `vf]C'
/** C2DAsSw
* GAh\6ul
* @author H8Z|gq1r
*/ $5Rx>$~+d
public class CountCache { B?
XK;*])
public static LinkedList list=new LinkedList(); oS_YQOoD
/** Creates a new instance of CountCache */ @?t+O'&
public CountCache() {} K>-01AGHL
public static void add(CountBean cb){ #X?E#^6?E
if(cb!=null){ /d$kz&aIV
list.add(cb); N4WX}
} A 0;ng2&
} e_1L J
} 5mm&l+N)
wV4MP1c$
CountControl.java >V>GiSni
%V#? 1{
/* 0P;LH3sx
* CountThread.java Nlu]f-i':
* t^~itlE{
* Created on 2007年1月1日, 下午4:57 Z)}2bJwA
* 0}g~69Z1=
* To change this template, choose Tools | Options and locate the template under T?7++mcA
* the Source Creation and Management node. Right-click the template and choose t\n'Kuk`
* Open. You can then make changes to the template in the Source Editor. 2>Qy*
*/ [X@JH6U
r
DJ!pZUO{
package com.tot.count; Pup%lO`.0
import tot.db.DBUtils; =n8M'
import java.sql.*; 6O*lZNN
/** >.hDt9@4
*
M{YN^
Kk
* @author (/!zHq
*/ Q>L.
public class CountControl{ @q{.shqo
private static long lastExecuteTime=0;//上次更新时间 nu[["f~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g5*?2D}dqX
/** Creates a new instance of CountThread */ /?}2OCq
public CountControl() {} aTBFF
public synchronized void executeUpdate(){ i\o * =+{r
Connection conn=null; CH5>u
PreparedStatement ps=null; d?/>Qqw:#
try{ [4;G^{
bX
conn = DBUtils.getConnection(); 6DC+8I<
conn.setAutoCommit(false); =pnQ?2Og
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); x,GLGGi}_x
for(int i=0;i<CountCache.list.size();i++){ p.x2R,CU
CountBean cb=(CountBean)CountCache.list.getFirst(); nrbP3sf*
CountCache.list.removeFirst(); d$n<^~Z
ps.setInt(1, cb.getCountId()); Z!l]v.S
ps.executeUpdate();⑴ RE08\gNIt
//ps.addBatch();⑵ dl3}\o_
} n
ON]YDg
//int [] counts = ps.executeBatch();⑶ Cli:;yi&n
conn.commit(); ##OCfCW
}catch(Exception e){ Qp>Z&LvC5
e.printStackTrace(); akWOE}5#
} finally{ Xv 7noq|
try{ BUyKiMW 49
if(ps!=null) { S{,|Fa^PPO
ps.clearParameters(); 8K&=]:(
ps.close(); 3XNk*Y[5
ps=null; &{ZUY3
} 4Wa*Pcj
}catch(SQLException e){} y'O<*~C(X
DBUtils.closeConnection(conn); 1r3}
V7
} $|AasT5w
} WDt 6{5T
public long getLast(){ *0<)PJ T
return lastExecuteTime; F]s:`4
} x1}Ono3"T
public void run(){ Uyd' uC
long now = System.currentTimeMillis(); F;BCSoO4
if ((now - lastExecuteTime) > executeSep) { ,}wFQ9*|W
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^S!;snhn
//System.out.print(" now:"+now+"\n"); xRqA^Ad
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); MXDUKh7v3
lastExecuteTime=now; Ms-)S7tMz
executeUpdate(); "ZFH_5<
} #WAX&<m
else{ a TPq1u
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); v3<q_J'qT
} ^Ww5@
} g1Osd7\o
} [c v!YE
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 -TS,~`O
8fPTxvXqL
类写好了,下面是在JSP中如下调用。 >oC{YYcK
`O0y8
<% d;{k,rP6
CountBean cb=new CountBean(); O9AFQ)u
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,
YlS
CountCache.add(cb); aDu[iaZ
out.print(CountCache.list.size()+"<br>"); n98sY+$-z
CountControl c=new CountControl(); ~Bi%8G
c.run(); 2HF`}H)H
out.print(CountCache.list.size()+"<br>"); Z_[L5B]Gwd
%>