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: v3!by N^
64;oB_
CountBean.java }%
FDm@+
bmSpbX\
/* }.w#X
* CountData.java >n#g9v K
* FC~|&
* Created on 2007年1月1日, 下午4:44 *%z<P~}
* 2>`m<&y
* To change this template, choose Tools | Options and locate the template under ^glbxbhI4
* the Source Creation and Management node. Right-click the template and choose M_|M&lR>
* Open. You can then make changes to the template in the Source Editor. )moo?Q
*/ Py}!C@e
\qRjXadj
package com.tot.count; nqUH6(
#r-j.f}yx
/** 0 [*nAo
* 38OIFT
* @author Z={UM/6w
*/
zd.1
public class CountBean { z[_R"+
private String countType; s=3EBh
int countId; 'JJ1#kKa
/** Creates a new instance of CountData */ LZ3rr-
public CountBean() {} }D8~^
public void setCountType(String countTypes){ k
QB 1=c
this.countType=countTypes; *_}IeNc
} LS*{]@8q
public void setCountId(int countIds){ mNGb}
lR
this.countId=countIds; V;/
XG}M
} 1nw$B[
public String getCountType(){ iW1$!l>v
return countType; ]JGKL5~p
} IiYuUN1D
public int getCountId(){ j&o/X7I=
return countId; =<Zwv\U
} >MBn2(\B;
} Oct\He\.
4Xa.r6T_N=
CountCache.java ksxO<Y
'Hcd&3a
/* H@ 1[SKBl
* CountCache.java kG_&-b
* e2,<,~_K6
* Created on 2007年1月1日, 下午5:01 tr#)iZ\
* ?Xy w<fMQ
* To change this template, choose Tools | Options and locate the template under @$K![]oD
* the Source Creation and Management node. Right-click the template and choose ;7B2~zL
* Open. You can then make changes to the template in the Source Editor. l{B<"+8
*/ 'd~, o[x
2_B;
package com.tot.count; ZlwcwoPib
import java.util.*; vr8J*36{
/** <yX@@8
* h$:&1jVY{
* @author /It.>1~2@
*/ FE^?U%:u@
public class CountCache { _Ct@1}aa4x
public static LinkedList list=new LinkedList(); [rD+8,zVm
/** Creates a new instance of CountCache */ =rs=8Ty?S
public CountCache() {} @k#z&@b
public static void add(CountBean cb){ m
bB\~n
if(cb!=null){ l7=$4As/hI
list.add(cb); oj,Vi-T Z
} -wG[>Y
} ^ mQ;CMV
} Wb*T
r!-L`GUm
CountControl.java 'Sb6
w+
7.F& {:@_
/* }(f,~?CP]
* CountThread.java $u0+29T2O
* AVdd?Ew
* Created on 2007年1月1日, 下午4:57 r5X BcG(2
* #I*ht0++
* To change this template, choose Tools | Options and locate the template under 7csl1|U
* the Source Creation and Management node. Right-click the template and choose -jklH/gF\%
* Open. You can then make changes to the template in the Source Editor. */fs.G:P
*/ yF [@W<
)BM WC
k
package com.tot.count; l{%Op\
import tot.db.DBUtils; 1^Y:XJ73
import java.sql.*; ,vHX>)M|
/** yA`]%U((
* [1[[$ Dr
* @author 0B!mEg
*/ ;Wp`th!F
public class CountControl{ e[|p0 ,Q
private static long lastExecuteTime=0;//上次更新时间 s$3eJ|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 F#3$p$;B$
/** Creates a new instance of CountThread */ r4z}yt+
public CountControl() {} gE]a*TOZk
public synchronized void executeUpdate(){ XV0<pV>
Connection conn=null; &*?!*+!,i
PreparedStatement ps=null; E<fwl1<88
try{ n"Z,-./m
conn = DBUtils.getConnection(); ?\/dfK:!
conn.setAutoCommit(false); [{d[f|
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); njx\$,ruN
for(int i=0;i<CountCache.list.size();i++){ O#89M%
CountBean cb=(CountBean)CountCache.list.getFirst(); VN55!l'OV
CountCache.list.removeFirst(); rg]A_(3Bb
ps.setInt(1, cb.getCountId()); -`ys pE0?
ps.executeUpdate();⑴ 1 _:1/~R1
//ps.addBatch();⑵ rym\5
`)
} L_CEY
//int [] counts = ps.executeBatch();⑶ XxrO:$
conn.commit(); NVM2\fs
}catch(Exception e){ |M{,}.*CU
e.printStackTrace(); ysw6hVb
} finally{ 'yAoZ P\|
try{ $SD@D6`lL
if(ps!=null) { P.2.Ge|
ps.clearParameters(); B39PDJ]hu
ps.close(); L-oPb)
ps=null; 4UX]S\X
} XP
Iu]F
}catch(SQLException e){} }E\+e!'!2
DBUtils.closeConnection(conn); Fw8X$SE"
} tg%WVy2
} 5eZg+ O
public long getLast(){ xQ(KmP2hl
return lastExecuteTime; dpOL1rrE
} nR|uAw
public void run(){ (>@syF%PB
long now = System.currentTimeMillis(); vp}>#&
if ((now - lastExecuteTime) > executeSep) { 8G^B%h]
//System.out.print("lastExecuteTime:"+lastExecuteTime); qI/r_
//System.out.print(" now:"+now+"\n"); T_|fb)G+{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
Dg2#Gv0B
lastExecuteTime=now; 2K7:gd8Ru
executeUpdate(); aN);P>
} 9.w3VF_C
else{ i|! 9o:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sMe~C>RD
} "%@=?X8
} GlkAJe]
} RBp(dKxM$w
//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 -<HvhW
uu46'aT
类写好了,下面是在JSP中如下调用。 yl]Cm?8
Ss#{K;
<% CIs1*:Q9
CountBean cb=new CountBean(); t2%bHIG}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 68G] a N3
CountCache.add(cb); 3@WI*PMc
out.print(CountCache.list.size()+"<br>"); U\!LZ?gC
CountControl c=new CountControl(); MxvxY,~{0
c.run(); +sq,!6#G
out.print(CountCache.list.size()+"<br>"); d'@H@
%>