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: {M?!nS6t
)>LC*_v
CountBean.java r4c3t,L*$I
Gr;~P*
/* \[+\JWJj
* CountData.java "Rp ]2'?
* $u4esg
* Created on 2007年1月1日, 下午4:44 nA]dQ+5sT
* C"IP1N
* To change this template, choose Tools | Options and locate the template under Fq5);sX=
* the Source Creation and Management node. Right-click the template and choose 0OMyE9jJJ
* Open. You can then make changes to the template in the Source Editor. []Z| *+=Q
*/ qt}[M|Q^r
yf=ek==
package com.tot.count; ~j\/3;^s
;6 1m
/** lC1X9Op
* "A:wWb<m
* @author | ~G;M*q
*/ LE Y Y{G?
public class CountBean { [<sBnHbvQ.
private String countType; AMYoSc
int countId; #U&G$E`7
/** Creates a new instance of CountData */ 'eo2a&S2D
public CountBean() {} 00G[`a5
public void setCountType(String countTypes){ QLH
s 3eM
this.countType=countTypes; ii*Ty!Sa
} <!zItFMD[m
public void setCountId(int countIds){ 5hp b=2
this.countId=countIds; j>s%q.
} DrltxI)
public String getCountType(){ C_#0Y_O
return countType; _TB\@)\
} m`9)DsR
N
public int getCountId(){ %'* |N[
return countId; ZF;S}1
} vfegIoZ
} |U^
ff^]
2uWzcy ?F
CountCache.java ,[bcyf
'EREut,>'
/* _uHyE }d
* CountCache.java kQIWDN
* M14_w,
* Created on 2007年1月1日, 下午5:01 &nn.h@zje
* %4L|#^7:
* To change this template, choose Tools | Options and locate the template under eOn,`B1
* the Source Creation and Management node. Right-click the template and choose fD\h5`-
* Open. You can then make changes to the template in the Source Editor. <$D)uY K
*/ FZA8@J|Q4
XpH[SRUx
package com.tot.count; =-`+4zB\
import java.util.*; 2%W(^Lj
/** 8`VMdo9
* ]hvB-R16f
* @author >uOc#+5M.
*/ v&XG4 &
public class CountCache { w.l#Z} k
public static LinkedList list=new LinkedList(); K)Db3JIIk
/** Creates a new instance of CountCache */ CaBTqo
public CountCache() {} &9s6p6eb
public static void add(CountBean cb){ $zmES tcm
if(cb!=null){ 2z[Pw0#V
list.add(cb); FcW ?([l
} Vn/6D[}Tu
} Gcs+@7!b
} Ya9uu@F
(rwbF
CountControl.java xJ&StN/'
h'-TZXs0e1
/* 2|%30i,vV
* CountThread.java ^1cqx]>E
* Y5MHd>m
* Created on 2007年1月1日, 下午4:57 ~hvhT}lE
* :za!!^
* To change this template, choose Tools | Options and locate the template under {J0^S
* the Source Creation and Management node. Right-click the template and choose //+UQgl6
* Open. You can then make changes to the template in the Source Editor. (`!|
Uf$
*/ %okEN!=
sa#"@j)
package com.tot.count; ,+X8?9v
import tot.db.DBUtils; c~RIl5j
import java.sql.*; |ntJ+
/** Pucf0 #
* CYrL|{M]
* @author _~cmR<
*/ OC>" +
public class CountControl{ IWT##']G
private static long lastExecuteTime=0;//上次更新时间 e;6Sj
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,OasT!Sr
/** Creates a new instance of CountThread */ sG VC+!E
public CountControl() {} MJg^
QVM
public synchronized void executeUpdate(){ f8&=D4)-w
Connection conn=null; ixS78KIr
PreparedStatement ps=null; C3_*o>8
try{ {9l4 pT3
conn = DBUtils.getConnection(); `\Npu
conn.setAutoCommit(false); MW$9,[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )@Zel.XD
for(int i=0;i<CountCache.list.size();i++){ v%FVz
CountBean cb=(CountBean)CountCache.list.getFirst(); lpp'.HTP
CountCache.list.removeFirst(); ,DE%p
+q
ps.setInt(1, cb.getCountId()); So8P8TCK
ps.executeUpdate();⑴ UJm`GO
//ps.addBatch();⑵ sJ?kp^!g
} W"Rii]GK"
//int [] counts = ps.executeBatch();⑶ Zwt!nh
conn.commit(); 8%|x)
}catch(Exception e){ gEe}xI
e.printStackTrace(); }%1E9u
} finally{ MoX*e
try{ fzKKK+
if(ps!=null) { 8p211MQ<
ps.clearParameters(); Z0'3.D,l
ps.close(); Rp<Xu6r
ps=null; rb_G0/R
} ZE\t{s0
}catch(SQLException e){} _N]yI0k(
DBUtils.closeConnection(conn); 9]YmP8
} cQ8:;-M
} y1'/@A1
public long getLast(){ vB
Jva8;Q
return lastExecuteTime; 16+@#d%#p
} @KpzxcEoO
public void run(){ l1:j/[B=
long now = System.currentTimeMillis(); /.?\P#9)
if ((now - lastExecuteTime) > executeSep) { DuE>KX{<!R
//System.out.print("lastExecuteTime:"+lastExecuteTime); {0LdLRNZ
//System.out.print(" now:"+now+"\n"); UF{2Gx
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,\m c.80
lastExecuteTime=now; .U3p~M+
executeUpdate(); f*5"Jh@
} v8 X&H
else{ UB1/FM4~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W#wM PsB
} "Dk:r/
} 5[R}MhLZ
} TB[vpTC9)
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 E7<:>Uh
j>T''Tf
类写好了,下面是在JSP中如下调用。 !^7:Rr_
[V f|4xcD
<% # SXXYh-e
CountBean cb=new CountBean(); B%pvk.`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Ov|j{}=L=9
CountCache.add(cb); b?^n'0
out.print(CountCache.list.size()+"<br>"); w#1dO~
CountControl c=new CountControl(); /{U{smtdFl
c.run(); ` WB|h)Y
out.print(CountCache.list.size()+"<br>"); @$*c0.
|z
%>