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: )#MKOsOct
sJX/YGHt
CountBean.java >U^AIaW
!arcQ:T@G
/* YWeEvo(,=
* CountData.java +~=>72/r
* g*ES[JJH&
* Created on 2007年1月1日, 下午4:44 .s|n}{D_i
* Z~8Xp
* To change this template, choose Tools | Options and locate the template under _> .TB\
* the Source Creation and Management node. Right-click the template and choose N~ljU;wo-9
* Open. You can then make changes to the template in the Source Editor. 9u1)Kr=e
*/ )_b#c+
yw5MlZ4P=
package com.tot.count; 4hztYOhJ{
epm
t
/** R! ?8F4G
* +&tY&dQQB
* @author *9%<}z
*/ E=w $r
public class CountBean { bslv_OxJ
private String countType; KO<fN,DR
int countId; g?UG6mFbE
/** Creates a new instance of CountData */ 1j6ZSE/*|
public CountBean() {} <\?ySto
public void setCountType(String countTypes){ Wt"@?#L
this.countType=countTypes; %,MCnu&Z
} 4pkc9\
public void setCountId(int countIds){ F&;g<
SD
this.countId=countIds; skdSK7 n
} pq*b"Jku1
public String getCountType(){ ppVjFCv0<
return countType; BgD;"GD*W
} GC H= X
public int getCountId(){ Mq42^m:qe
return countId; j*Q/vY!T
} Gp$[u4-6M6
} Gu~y/CE'
e>1^i;f
CountCache.java q#I/N$F
Jd&Qi)1
/* P
/wc9Yt
* CountCache.java A) p}AEBc
* \,[Qg#W$u
* Created on 2007年1月1日, 下午5:01 'Y6{89 y
* Kom$i<O?48
* To change this template, choose Tools | Options and locate the template under TF|GGYi
* the Source Creation and Management node. Right-click the template and choose )rz4IfE
* Open. You can then make changes to the template in the Source Editor. o&g=Z4jj<
*/ 6<NaME
W$N_GR'4
package com.tot.count; s>~!r.GC
import java.util.*; (G}*ho
/** ;7 i0ko9
* >
zh%CF$
* @author aC X](sN
*/ {{f%w$r(
public class CountCache { w48T?
public static LinkedList list=new LinkedList();
q>r9ooN
/** Creates a new instance of CountCache */ B c*Rn3i@
public CountCache() {} A2uSH@4
public static void add(CountBean cb){ XV)ej>A-V
if(cb!=null){ l+bP48
list.add(cb); Hy|$7]1
} 4eYj.=I
} R8Lp8!F'
} TuBg 4\V
HV&N(;@
CountControl.java &B#HgWud
`BMg\2Ud*
/* @8|- C
* CountThread.java 9Z6] ];8E
* rYeFYPS
* Created on 2007年1月1日, 下午4:57 rcq(p(!
* #; E,>0
* To change this template, choose Tools | Options and locate the template under jIZQ/xp8_
* the Source Creation and Management node. Right-click the template and choose 8~EDmg[
* Open. You can then make changes to the template in the Source Editor. wz9V)_V*
*/ iF{eGi
_,NL;66=[
package com.tot.count; W*u Yb|0
import tot.db.DBUtils; 9O?.0L
import java.sql.*; Bb]pUb
/**
):+n!P
*
qeBfE
* @author EHcqj;@m
*/ X;v/$=-mz
public class CountControl{ =:1f
0QF
private static long lastExecuteTime=0;//上次更新时间 "xa<Q%hk
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 j?+FS`a!
/** Creates a new instance of CountThread */ 4bhm1Q
public CountControl() {} y{s?]hLk
public synchronized void executeUpdate(){ 1*[h$Z&H?
Connection conn=null; t\CVL?e`
PreparedStatement ps=null; 5(%+8<2
try{ NV9D;g$Y
conn = DBUtils.getConnection(); b@Ik
c<
conn.setAutoCommit(false); -mO[;lO
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); iwJBhu0@#
for(int i=0;i<CountCache.list.size();i++){ \QBODJ1
CountBean cb=(CountBean)CountCache.list.getFirst(); 6BFtY+.y
CountCache.list.removeFirst(); 8K]fw{-$L
ps.setInt(1, cb.getCountId()); .O3i"X]
ps.executeUpdate();⑴ pYI`5B4
//ps.addBatch();⑵ g>_6O[;t%
} (pH13qU5
//int [] counts = ps.executeBatch();⑶ >72j,0=e
conn.commit(); u#\=g:
}catch(Exception e){ | 5Mhrb4.
e.printStackTrace(); 3:YZC9
} finally{ R8c1~'
try{ 8PDt 7
\
if(ps!=null) { 9&g//JlD
ps.clearParameters(); p` B48TW
ps.close(); 'vhgR2/
ps=null; |UZ#2
} p;"pTGoWi
}catch(SQLException e){} E&#AX:
DBUtils.closeConnection(conn); vy,ER<
} FaPX[{_E
} m%+W{N4Wb
public long getLast(){ 0 4x[@f`
return lastExecuteTime;
*"P
:ySA
} Cl6y:21]K
public void run(){ 1[[`
^v
long now = System.currentTimeMillis(); AJiEyAC!)5
if ((now - lastExecuteTime) > executeSep) { $iEM$
//System.out.print("lastExecuteTime:"+lastExecuteTime); 62PtR`b>
//System.out.print(" now:"+now+"\n"); \d&j`UVY
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); bguhx3s
lastExecuteTime=now; M9_
y>N[0
executeUpdate(); a,#f%#J\
} I$n 0aR6
else{ ..Zuy|?w
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 5:hajXd
} aM9^V MOb
} 9FP6Z[4
} ' 6Ybf
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 1wW8D>f]K
PQa{5"
类写好了,下面是在JSP中如下调用。 KX"?3#U#Fm
t*.O >$[
<% o`+6E
q0w
CountBean cb=new CountBean(); XK`>#*"V
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); yXh=~:1~
CountCache.add(cb); {[jcT>.3j
out.print(CountCache.list.size()+"<br>"); 5H6m{ng
CountControl c=new CountControl(); 0F1 a
c.run(); w+=>b
out.print(CountCache.list.size()+"<br>"); 54JZEc
%>