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: ~][~aEat;V
gLv+L]BnhH
CountBean.java aA|{r/.10K
%[p*6&V
/* `}),wBq
* CountData.java zVS{X=u
* 1YV1Xnn,
* Created on 2007年1月1日, 下午4:44 6m;>R%S_
* *m"9F'(Sd
* To change this template, choose Tools | Options and locate the template under 9xK>fM&u
* the Source Creation and Management node. Right-click the template and choose w"9h_;'C_
* Open. You can then make changes to the template in the Source Editor. Z5q%L!4G
*/ ~JL
qh
_VT{2`|})
package com.tot.count; b\}a
caQ1SV^{9
/** V|'@D#\
* "mJo<i}
* @author l ubsL I
*/ #EzhtuHxn
public class CountBean { Z{^!z
private String countType; s9wzN6re
int countId; -t4:%-wv
/** Creates a new instance of CountData */ *LB-V%{|'
public CountBean() {} /+92DV
public void setCountType(String countTypes){ Cb+sE"x]
this.countType=countTypes; "rn
} Z3TCi7,m
public void setCountId(int countIds){ {A0F/#M]
this.countId=countIds; 6)^*DJy
} \XB,)XDB
public String getCountType(){ FvT4?7-
return countType; W8 g13oAu"
} }'P|A
public int getCountId(){ SSF:PTeG>
return countId; MM32\}Y6
} M$EF 8
} UmVn: a
<9pI~\@w
CountCache.java "QOQ
g4WmUV#wp
/* D=a*Xu2zq
* CountCache.java ;&j'`tP
* )W\)kDh!
* Created on 2007年1月1日, 下午5:01 wnX;eU/n
* O<s7VHj
* To change this template, choose Tools | Options and locate the template under .\a+m
* the Source Creation and Management node. Right-click the template and choose ]x
metv|7
* Open. You can then make changes to the template in the Source Editor. 55O}S Us!P
*/ VjWJx^ZL#
i<Ms2^
package com.tot.count; q<E7qY+
import java.util.*; c/K#W$ l
/** e W8cI)wU
* 6h/!,j0:t_
* @author ^ZsIQ4 @`
*/ tQzbYzGb7
public class CountCache { @M\JzV4 A[
public static LinkedList list=new LinkedList(); !6|_`l>G,
/** Creates a new instance of CountCache */ j4i$2ZT'
public CountCache() {} OG<*&V
public static void add(CountBean cb){ WDY\Fj
if(cb!=null){ I '0[
list.add(cb); _]*[TGap
} Mt4]\pMUb
} |gA@$1+}
} 9q?knMt
5]*lH t
CountControl.java esSj
3E
mfZbo#KS#v
/* rrU(>jA!
* CountThread.java (Yj6|`
* Q)aoc.f!v
* Created on 2007年1月1日, 下午4:57 ;0WAfu}#H
* <T7@,_T
* To change this template, choose Tools | Options and locate the template under S<]k0bC
* the Source Creation and Management node. Right-click the template and choose Ia](CN*;6
* Open. You can then make changes to the template in the Source Editor. ek)rsxf1A
*/ TSFrv8L
Z|@-=S(.
package com.tot.count; lJAzG,f
import tot.db.DBUtils; kVtP~
import java.sql.*; *P
*.'XM
/** :c]y/lQmV
* ~*EipxhstJ
* @author a)2l9
*/ %u%;L+0Q[
public class CountControl{ ypM,i
private static long lastExecuteTime=0;//上次更新时间 Aa1#Ew<r
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 9Y2u/|!.3
/** Creates a new instance of CountThread */ ;
]%fFcy
public CountControl() {} }%w;@[@L
public synchronized void executeUpdate(){ K_U`T;Z\
Connection conn=null; .nIGs'P
PreparedStatement ps=null; $]?pAqU\
try{ 27gHgz}}
conn = DBUtils.getConnection(); 0*:n<T9
conn.setAutoCommit(false); h(q4
B~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); BpA7
z /
for(int i=0;i<CountCache.list.size();i++){ KD#zsL)3
CountBean cb=(CountBean)CountCache.list.getFirst(); >;G_o="X
CountCache.list.removeFirst(); d3E N0e+^
ps.setInt(1, cb.getCountId()); oa+'.b~
ps.executeUpdate();⑴ ui8$ F
"I*
//ps.addBatch();⑵ <8%+-[(
} vH6(p(l
//int [] counts = ps.executeBatch();⑶ >7a
ENKOg:
conn.commit(); j*8Ze!^
}catch(Exception e){ %zc.b
e.printStackTrace(); !pe[H*Cy
} finally{ XKp(31])
try{ 7202N?a
{
if(ps!=null) { r8R7@S2V'
ps.clearParameters(); 2O(k@M5E?
ps.close(); UV%o&tv|<
ps=null; b^[>\s'
} :F5(]g 7
}catch(SQLException e){} 6R m d t
DBUtils.closeConnection(conn); )`k+Oyvi<
} >.39OQ#
} e{2Za
public long getLast(){ 0F!Uai1
return lastExecuteTime; fc:87ZR{K
} 7g8\q@',
public void run(){ im>/$!&OyI
long now = System.currentTimeMillis(); `o_i+?E
if ((now - lastExecuteTime) > executeSep) { i]zh8|">
//System.out.print("lastExecuteTime:"+lastExecuteTime); x?6^EB|@
//System.out.print(" now:"+now+"\n"); +Rd\*b
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); RU.j[8N$
lastExecuteTime=now; LCRWC`%&
executeUpdate(); hBZh0xy
} :n<l0
else{ d?U,}tv
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); fX:G;vYn
} Lo'GfHE
} QncjSaEE
} S%
ptG$Z
//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 Y,n8co^
*s1o?'e
类写好了,下面是在JSP中如下调用。 ZWFOC,)b
31g1zdT!
<% ^l(,'>Cn
CountBean cb=new CountBean(); 3Qv9=q|[b
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); fm%4ab30T
CountCache.add(cb); ,9:v2=C_
out.print(CountCache.list.size()+"<br>"); 2DZ&g\|
CountControl c=new CountControl(); YS9)%F=X
c.run(); 'bji2#z[
out.print(CountCache.list.size()+"<br>"); '6WZi|(a
%>