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: {ex]_V>
6BnjT
CountBean.java '4rgIs3=x"
+#no$m.bH
/* 5`Bb0=j
* CountData.java @[Th{HTc.G
* <PxEl4
* Created on 2007年1月1日, 下午4:44 Fh'Jb*|Q
* mqL+W
* To change this template, choose Tools | Options and locate the template under <#-ERQw
* the Source Creation and Management node. Right-click the template and choose )j]RFt
* Open. You can then make changes to the template in the Source Editor. Lnzhs;7L
*/ ;Mz]uk
7Fp2=j
package com.tot.count; ,J~dER\%
.\ZxwD|
/** :lAR;[WFS
* (hoqLL\}k
* @author xjYFTb}!
*/ ;z68`P-
public class CountBean { =3'wHl
private String countType; _u0dt) $
int countId; h|
Ih4
/** Creates a new instance of CountData */ Sa0\93oa
public CountBean() {} 0Ju{6x(|
public void setCountType(String countTypes){ >Vvc55z
this.countType=countTypes; Evc
9k
} &}r932
public void setCountId(int countIds){ X {$gdz8S9
this.countId=countIds; 1X5\VY>S`h
} ;k0*@c*
public String getCountType(){ fOJyY[
return countType; dj=n1f+;[
} };*5+XY^
public int getCountId(){ RwE]t$T/
return countId; \3l;PY
} -l",!sV
} LM}si|
Ud](hp"
CountCache.java = U5)m
?2M15Q
/* c1`o3gb
* CountCache.java TsQMwV_h
* aF:I]]TfK~
* Created on 2007年1月1日, 下午5:01 1\McsX4
* p82qFzq#
* To change this template, choose Tools | Options and locate the template under i=ba=-"Mt
* the Source Creation and Management node. Right-click the template and choose ]O[f#lG
* Open. You can then make changes to the template in the Source Editor. sYz:(hZS
*/ ]mp.KvB
__QTlj
package com.tot.count; KH;e)91
import java.util.*; eR/7*G5
/** a4wh-35/
* 3eB2=_V`
* @author (8I0%n}.Zo
*/ Gi-tf<
public class CountCache { ?}y7S]B FI
public static LinkedList list=new LinkedList(); Ul=`]@]]
/** Creates a new instance of CountCache */ Abl=Ev
public CountCache() {} AA66^/t
public static void add(CountBean cb){ p7*\]HyE)
if(cb!=null){ vq{:=:5'P
list.add(cb); R1nctA:
} O/Fzw^
} A1|:$tED+2
} 'g#))y
'D1@+FFU0
CountControl.java X#J[Nn>
u^ T2
/* c[5>kQ-nq
* CountThread.java vF_?1|*|
* 0iYe>u
* Created on 2007年1月1日, 下午4:57 /ZczfM\
* k: {$M yK
* To change this template, choose Tools | Options and locate the template under M! s&<Bi
* the Source Creation and Management node. Right-click the template and choose =$m|M
m[a
* Open. You can then make changes to the template in the Source Editor. I=1tf;Bsi
*/ 6} 9A0
O:#to
package com.tot.count; m,pDjf
import tot.db.DBUtils; i_MDLS>-
import java.sql.*; x*YJ:t
/** &t4j px
* mJT7e
* @author ua0k)4|
*/ MW p^.
public class CountControl{ M?_VYK
private static long lastExecuteTime=0;//上次更新时间 03MB,
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4'{j'kuv
/** Creates a new instance of CountThread */ $tb$gO
public CountControl() {} bC&_OU:
public synchronized void executeUpdate(){ _+UD>u{
Connection conn=null; MPT[f
PreparedStatement ps=null; X1+Wb9P
try{ ,3^N_>d$W
conn = DBUtils.getConnection(); Tj>~#~
conn.setAutoCommit(false); i$ Zhk1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Xdjxt?*
for(int i=0;i<CountCache.list.size();i++){ *bZV4}
CountBean cb=(CountBean)CountCache.list.getFirst(); !D1F4v[c=
CountCache.list.removeFirst(); RY*6TYX!
ps.setInt(1, cb.getCountId()); I3SLR
ps.executeUpdate();⑴ a/?gp>M9
//ps.addBatch();⑵ #Zfg
} %DiZ&}^Ck
//int [] counts = ps.executeBatch();⑶ PPohpdd)
conn.commit(); bzZEwMc6
}catch(Exception e){ /$B<+;L!#
e.printStackTrace(); L%<1cE))
} finally{ (ttO
O45
try{ Chjth"
if(ps!=null) { iX4/;2B=,
ps.clearParameters(); 9m<>G3Jr
ps.close(); d(h`bOjI
ps=null; {4#'`Eejj
} byd[pnI$H
}catch(SQLException e){} Ij#?r2Z%
DBUtils.closeConnection(conn); lT*Hj.
} '*22j ]
} bj7v <G|Y
public long getLast(){ k{9s>l~'
return lastExecuteTime; 5HmX-+XpK
} y*P[*/g
public void run(){ c/pT2/y
long now = System.currentTimeMillis(); lqu1H&
if ((now - lastExecuteTime) > executeSep) { HmQuRW
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y,?rykRj
//System.out.print(" now:"+now+"\n"); @
j'I
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); N>VA`+aFR
lastExecuteTime=now; n-p|7N
executeUpdate(); Cgt{5
} Dtelr=/s
else{ Nk]r2^.z[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [t,7H
} l^fz
} JgEpqA12
} qdzc"-gH`
//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 r lW
)V+;7j<"D
类写好了,下面是在JSP中如下调用。 >?I[dYzut
g,9o'fs`x
<% J8(v65
CountBean cb=new CountBean(); U2!9Tl9".
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !K_%@|: 7%
CountCache.add(cb); >`u} G1T\
out.print(CountCache.list.size()+"<br>"); MLaH("aen
CountControl c=new CountControl(); eFbr1IV
c.run(); g3j@o/Y
out.print(CountCache.list.size()+"<br>"); WFy90*@Z
%>