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: -TgUyv.
=nzFd-P
CountBean.java %*6RzJO6
sc%dh?m7
/* `4LJ;KC(
* CountData.java ;d4y{
* `qE4U4
* Created on 2007年1月1日, 下午4:44 J;~E<_"Hn
* N r<9u$d9=
* To change this template, choose Tools | Options and locate the template under TFO74^
* the Source Creation and Management node. Right-click the template and choose i-b1d'?Rb
* Open. You can then make changes to the template in the Source Editor. r&SO:#rOSM
*/ I:F
<vE
/u=aX
package com.tot.count; >5.zk1&H
@l{I[pp
/** )S2iIi;Bq
* G;NB\3~X
* @author AP0|z
*/ I] jX7.fx
public class CountBean { "J& (:(:
private String countType; k52QaMKa~A
int countId; &3I$8v|!?
/** Creates a new instance of CountData */ usy,V"{
public CountBean() {} UeA2c_
5
public void setCountType(String countTypes){ IP04l;p/
this.countType=countTypes; gGI8t@t:
} >60"p~t
public void setCountId(int countIds){ uoHqL IpQ
this.countId=countIds; .U 39nd
} U+} y
%3l
public String getCountType(){ as(*B-_n~
return countType; >b>gr OX
} UT4f (Xo
public int getCountId(){ G,]z(%
return countId; bEd?^h
} zks#EzQ
} J?IC~5*2
N!L'W\H,
CountCache.java Pu..NPl+
!R74J=#(
/* |<rfvsQ.
* CountCache.java `E W!-v)
* <1
S+'
* Created on 2007年1月1日, 下午5:01 9`BEi(z
* &\k?xN
* To change this template, choose Tools | Options and locate the template under zw]3Vg{T
* the Source Creation and Management node. Right-click the template and choose q!&B6]
* Open. You can then make changes to the template in the Source Editor. t!{x<9
*/ l<xFnj
+*C^:^jA
package com.tot.count; gLD{1-v
import java.util.*; f*<ps
o
/** !!WJn}
* c;wA
* @author MqdB\OW&
*/ -2 xE#r
public class CountCache { &DLhb90
public static LinkedList list=new LinkedList(); i=L8=8B`
/** Creates a new instance of CountCache */ 1"O&40l
public CountCache() {} 4)^vMG&
public static void add(CountBean cb){ 3D[=b%2\
if(cb!=null){ O:JPJ"!
list.add(cb); >jMH#TZaX
} "15=ET
} | 3giZ{
} C2G |?=
>S'>!w
CountControl.java IY)5.E
_
E*k([ZL
/* TV=c,*TV
* CountThread.java bnr|Y!T}Bi
* s@~/x5jwCs
* Created on 2007年1月1日, 下午4:57 t#5:\U5r.
* y9!:^kDI
* To change this template, choose Tools | Options and locate the template under sJ~P:g
* the Source Creation and Management node. Right-click the template and choose c&*l"
* Open. You can then make changes to the template in the Source Editor. hk}
t:<
*/ 5
`=KyHi:b
t77'fm
package com.tot.count; Ea]T>4
import tot.db.DBUtils; v459},!P
import java.sql.*; o1k#."wHr
/** F;kvH
* KjOi(YUnq7
* @author @9vvR7{P
*/ tOH0IE c
public class CountControl{ zMGzReJ
private static long lastExecuteTime=0;//上次更新时间 tS<h8g_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 -:SIS`0s
/** Creates a new instance of CountThread */ nU17L6'$
public CountControl() {} PN
&|8_
public synchronized void executeUpdate(){ azX`oU,l
Connection conn=null; )%VCzye*{
PreparedStatement ps=null; GV8)Kor%
try{ lFfXWNb
conn = DBUtils.getConnection(); .C= I^
conn.setAutoCommit(false); s.:r;%a
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); aZKXD! 4
for(int i=0;i<CountCache.list.size();i++){ #
X/Q
CountBean cb=(CountBean)CountCache.list.getFirst(); J3B.-XJ+n
CountCache.list.removeFirst(); VR4%v9[1
ps.setInt(1, cb.getCountId()); gS$A
ps.executeUpdate();⑴ 4AHL3@x
//ps.addBatch();⑵ <%K UdkzEP
} ? )_7U
//int [] counts = ps.executeBatch();⑶ i03gX<=*
conn.commit(); t`u!]DHv
}catch(Exception e){ 7'OPjtM
e.printStackTrace(); j=ihbR^]Tl
} finally{ Q2c*.Y
try{ ezZph"&
if(ps!=null) { Ttv'k*$cP
ps.clearParameters(); O]qPmEj
ps.close(); v!trsjb
ps=null; 2B` 8eb
} +< KNY
}catch(SQLException e){} "}zda*z8
DBUtils.closeConnection(conn); VAKy^nR5j
} Mr*|9h
} S$O,] @)
public long getLast(){ +(mL~td01
return lastExecuteTime; uTGcQs}
} @~o`#$*|
public void run(){ 54q3R`y
long now = System.currentTimeMillis(); 8=Q VN_
if ((now - lastExecuteTime) > executeSep) { Y6ben7j%-
//System.out.print("lastExecuteTime:"+lastExecuteTime); cy1jZ1)
//System.out.print(" now:"+now+"\n"); doD>m?rig3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ><Uk*mwL
lastExecuteTime=now; <AUWby,"
executeUpdate(); /s[DI;M$o
} bk3Unreh
else{ )N7n,_#T>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'msmXX@q
} >IY,be6>P
} 5AOfp2O
} 2OalAY6RS
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Jqru AW<
>Z\BfH
类写好了,下面是在JSP中如下调用。 ]a/'6GbR
/2@["*^$
<% 4;*f1_;f~
CountBean cb=new CountBean(); X/+OF'po
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0 {R/<N
CountCache.add(cb); I/B1qw;MN
out.print(CountCache.list.size()+"<br>"); VXIQw'Cq
CountControl c=new CountControl(); XP;x@I#l
c.run(); ~>%DKJe
out.print(CountCache.list.size()+"<br>"); (1){A8=?o
%>