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: 9%m^^OOf
OM`Ws5W}f
CountBean.java
~D`
U99Uny9
/* Cm0K-~
U
* CountData.java A7T(p7pP
* uC[F'\Y
* Created on 2007年1月1日, 下午4:44 0C6T>E7
* 7y$U$6
* To change this template, choose Tools | Options and locate the template under ME.!l6lm\
* the Source Creation and Management node. Right-click the template and choose Qtt3;5m
* Open. You can then make changes to the template in the Source Editor. |D[LU[<C
*/ pIKfTkSqH
E
`V?Io
package com.tot.count; >4Qj+ou
x1"8K
/** N(O*"1b
* N Ff`V
* @author 0W~1v
*/ c_aj-`BKp
public class CountBean { kZR(0,
W
private String countType; dl6Ju
int countId; f=Oj01Ut*
/** Creates a new instance of CountData */ .\3gb6S}
public CountBean() {} 4E$d"D5]>p
public void setCountType(String countTypes){ \{qtdTd
this.countType=countTypes; 9S<V5$}
} K?yMy,9%Yw
public void setCountId(int countIds){ 7Jpq7;
this.countId=countIds; JM53sx4&
} <L2z| %`
public String getCountType(){ H8m[:K]_H
return countType; R{6M(!x
} <@y(ikp>
public int getCountId(){ `X B$t?xi
return countId; 3ik~PgGoKQ
} }|nEbM]#
} at\$
IK_
urQ<r{$x0
CountCache.java v9Lf|FXo&
k4` %.;
/* i1 GQ=@
* CountCache.java AdzdYZiM_
* s=Kz9WLy
* Created on 2007年1月1日, 下午5:01 &3itBQF
* =p dLh
* To change this template, choose Tools | Options and locate the template under ViUx^e\
* the Source Creation and Management node. Right-click the template and choose }n
+MVJ;dG
* Open. You can then make changes to the template in the Source Editor. hI*6f3Vn(n
*/ 'u_j5
W'e{2u
package com.tot.count; O@skd2
import java.util.*; mqY=N~/O
/** F3x*dq2
* cb/$P!j7
* @author ziv+*Qn_b4
*/ ?ea5k*#a
public class CountCache { Gsz$H_
public static LinkedList list=new LinkedList(); ]}.|b6\
/** Creates a new instance of CountCache */ V|<'o<h8
public CountCache() {} lQ4$d{m`
public static void add(CountBean cb){ Q,};O$h
if(cb!=null){ g+xcKfN{
list.add(cb); $-
Y8@bw
} X G5"u
} 7UUu1"|a|
} \vuWypo
!P6?nS
CountControl.java ;Q[E>j?w=
q3|SZoN
/* Qz$Wp*
* CountThread.java TZdJq
* \7e4t
* Created on 2007年1月1日, 下午4:57 KYq<n& s
* IU"8.(;o
* To change this template, choose Tools | Options and locate the template under ly@%1
* the Source Creation and Management node. Right-click the template and choose }s8xr>
* Open. You can then make changes to the template in the Source Editor. R?J8#JPXD
*/ Q v},X~^R
g9IIC5
package com.tot.count; JtF)jRB0,
import tot.db.DBUtils; 0QEcJ]Qb8
import java.sql.*; i;:}{G<
/** &7Xsn^opku
* ~N)(|N
* @author $-(lp0\*
*/
8L`wib2
public class CountControl{ YI]/gWeu
private static long lastExecuteTime=0;//上次更新时间 xJOp~fKG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |{rhks~
/** Creates a new instance of CountThread */ 9MbF:
public CountControl() {} 4% 6@MQ[
public synchronized void executeUpdate(){ 0;w84>M
Connection conn=null; Hdjp^O!
PreparedStatement ps=null; \JP9lJ3<
try{ zY].ZS=7
conn = DBUtils.getConnection(); .mxc~
conn.setAutoCommit(false); %PPkT]~\
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2Ic)]6z
R
for(int i=0;i<CountCache.list.size();i++){ CYM>4C~>JW
CountBean cb=(CountBean)CountCache.list.getFirst(); 8/~@3-9EK
CountCache.list.removeFirst(); ?}C8_I|4~
ps.setInt(1, cb.getCountId()); m`4N1egCt
ps.executeUpdate();⑴ KSUhB
//ps.addBatch();⑵ ~x J#NC+
} CU/Id`"tW
//int [] counts = ps.executeBatch();⑶ 1`Uu;mz
conn.commit(); #.LI`nYA
}catch(Exception e){ Ol;"}3*Z*
e.printStackTrace(); f^Q)lIv
} finally{ Q{~;4+ZD
try{ gU?M/i2
if(ps!=null) { B.);Ju
ps.clearParameters(); g$z6*bL
ps.close(); +Edq4QYwR
ps=null; w~n+hhMF
} p#>,{
}catch(SQLException e){} V! .I>
DBUtils.closeConnection(conn); j3[kG#
} G420o}q
} Z,>owoP4
public long getLast(){ (T.j3@Ko
return lastExecuteTime; ixqvX4vv,B
} C
*7x7|z
public void run(){
9q2x}
long now = System.currentTimeMillis(); z\K-KD{Ad
if ((now - lastExecuteTime) > executeSep) { WqHp23
//System.out.print("lastExecuteTime:"+lastExecuteTime); .AF\[IQ
//System.out.print(" now:"+now+"\n"); k~JTQh*,w
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .8wF>
8
lastExecuteTime=now; S=$ \S9
executeUpdate(); QO4eDSW
} NkAu<>
G _
else{ LfvRH?<W
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'Xasd3*Py
} t;y@;?~
} >Hd!o"I
} hKems3
//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 NQN?CBFQ
zGP@!R`_
类写好了,下面是在JSP中如下调用。 9zpOp-K6
f2ck=3
<% m-Se-aF
CountBean cb=new CountBean(); 6-\M }xq?
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 6dRvx;d
CountCache.add(cb); OZe`>Q6
out.print(CountCache.list.size()+"<br>"); 1.nYT*
CountControl c=new CountControl(); R!>SN0
c.run(); !{A#\~,
out.print(CountCache.list.size()+"<br>"); Jn20^YG
%>