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: {7pE9R 5
u
UVV>An
CountBean.java v\?\(Y55Y
c;t(j'k`
/* ee d\0
* CountData.java P+zI9~N[
* @x-GbK?
* Created on 2007年1月1日, 下午4:44 o7 -h'b-
* C"m0"O>
* To change this template, choose Tools | Options and locate the template under tpx3:|
* the Source Creation and Management node. Right-click the template and choose -)vp&-
* Open. You can then make changes to the template in the Source Editor. n]ppO
U|[
*/ c&I,eds
4iPua"8
package com.tot.count; B|q3;P
!,(bXa\^
/** GE3U0w6WbK
* Y;/=3T7An
* @author ID k:jO
*/ OTFu4"]M
public class CountBean { Ci#5@Q9#w
private String countType; S>ylA U;N
int countId; .pu`\BW>
/** Creates a new instance of CountData */ `bi_)i6Low
public CountBean() {} fPk9(X;G!p
public void setCountType(String countTypes){ b8b PK<
this.countType=countTypes; ``YL]
<<
} B43#9CK`o
public void setCountId(int countIds){ szsZFyW)+
this.countId=countIds; %},S#5L3
} PK`(qK9
public String getCountType(){ Xde=}9
return countType; r0$9c
} C2,cyhr
public int getCountId(){ X9`C2fyVd
return countId; \3:{LOr%*
} "}x70q'>S
} `_{'?II
\3Ald.EqtM
CountCache.java @XG`D>%k
+sbacMfq
/* [;LPeO
* CountCache.java 6pz:Lfd80
* AU?YZEAei
* Created on 2007年1月1日, 下午5:01 h}:5hi Jw
* {R8P $
* To change this template, choose Tools | Options and locate the template under jeuNTDjeL
* the Source Creation and Management node. Right-click the template and choose .STf
* Open. You can then make changes to the template in the Source Editor. u(G;57ms
*/ (lck6v?h
PQ#-.K
package com.tot.count; |`D5XRVbi
import java.util.*; Q@.9wEAJ
/** _.8]7f`*Gc
* ^l2d?v8
* @author ;@-5lCvC(+
*/
! +VN
public class CountCache { 9DAwC:<r
public static LinkedList list=new LinkedList(); =/'*(\C2
/** Creates a new instance of CountCache */ -8kW!F
public CountCache() {} Eq.zCD8A
public static void add(CountBean cb){ nhxd
if(cb!=null){ K[;,/:Y
list.add(cb); U[ O!&:6
} vc1GmB
} ~4X!8b_
} /Ta0}Y(y
3)MM5
bb$
CountControl.java iC0,zk4 &
~S{\wL53
/* ZC-evy
* CountThread.java WoG
* Oy`\8*Uy__
* Created on 2007年1月1日, 下午4:57 =xWW+w!r
* oW1olmpp=
* To change this template, choose Tools | Options and locate the template under D~?*Xv]s~
* the Source Creation and Management node. Right-click the template and choose n[S*gX0
* Open. You can then make changes to the template in the Source Editor. 7XC}C+
*/ CpdY)SMSL
5<8>G?Y
package com.tot.count; f2e$BA
import tot.db.DBUtils; r|BKp,u9
import java.sql.*; _^sSI<&m
/** ^
J@i7FOb
* #"YWz)8
* @author -ddatc|
*/ x=|@AFI
public class CountControl{ I:)#U[tn0
private static long lastExecuteTime=0;//上次更新时间 1`JN
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 $[;eb,
/** Creates a new instance of CountThread */ \J
g#X:d
public CountControl() {} F88SV6
public synchronized void executeUpdate(){ Pw{{+PBu R
Connection conn=null; @%85k/(
PreparedStatement ps=null; .{ L m
try{ 3'uES4+r
conn = DBUtils.getConnection(); Z"nuO\zH~
conn.setAutoCommit(false); #Z5Wk
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 3>3ZfFC
for(int i=0;i<CountCache.list.size();i++){ KEB>}_[
CountBean cb=(CountBean)CountCache.list.getFirst(); /FZ )ej\
CountCache.list.removeFirst(); tD482Sb=
ps.setInt(1, cb.getCountId()); U,}T ]J
ps.executeUpdate();⑴ T $]L 5
//ps.addBatch();⑵ dOgM9P
} ptL}F~
//int [] counts = ps.executeBatch();⑶ %pKs- n`
conn.commit(); h0QQP
}catch(Exception e){ AQGE(%X
e.printStackTrace(); u+FftgA
} finally{ aVL%-Il}
try{ j'b4Sbs-f
if(ps!=null) { 4KB?g7_*
ps.clearParameters(); 5.UgJ/
ps.close(); J, U~.c
ps=null; ?Og ;W9i
} D"aQbQP
}catch(SQLException e){} 6j![m+vo%
DBUtils.closeConnection(conn); WoR**J?}w
} 5 :>
} v333z<<S
public long getLast(){ 4B>|Wft{p]
return lastExecuteTime; 8j+;Xlh
} E*"E{E7
public void run(){ Ykq }9
long now = System.currentTimeMillis(); $)a5;--W
if ((now - lastExecuteTime) > executeSep) { @TG~fJSA12
//System.out.print("lastExecuteTime:"+lastExecuteTime); 2xm?,p`
//System.out.print(" now:"+now+"\n"); AU\!5+RDB
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?%n9g)>Yej
lastExecuteTime=now; v)pWx0l=
executeUpdate(); $
$+z^%'_
} O/@ [VPf
else{ [$+61n}.12
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ho<#i(
} 9 peB+URV
} ]&BFV%kw
} 3Or3@e5r
//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 b=go"sJ@>(
Um&@
0C+L
类写好了,下面是在JSP中如下调用。 2l%iXK[
2Vr'AEIQ
<% q@>
m~R
CountBean cb=new CountBean(); t')I c6.?i
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); m>:ig\
CountCache.add(cb); nJw1Sl5
out.print(CountCache.list.size()+"<br>"); l,8|E
CountControl c=new CountControl(); #r}c<?>Vw
c.run(); 9LRY
out.print(CountCache.list.size()+"<br>"); -OAH6U9^
%>