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: h~t]WN
@,.H)\a4
CountBean.java $!lxVZ>
Ho|n\7$
/* Rwk|cqr
* CountData.java H*IoJL6
* *z~Y *Q0
* Created on 2007年1月1日, 下午4:44 @"0qS:s]X
* l.!
~t1i
* To change this template, choose Tools | Options and locate the template under z/=v@@tj
* the Source Creation and Management node. Right-click the template and choose !b=$FOC>
* Open. You can then make changes to the template in the Source Editor. 0Jrk(k!
*/ c$;enAf@
F9" K
package com.tot.count; 75u*ZMK
HIAd"}^
/** 'M{_S
* R_}(p2
* @author U_?RN)>j
*/ ;.Y`T/eWS
public class CountBean { A{vG@Pwc:
private String countType; M?o`tWLhF
int countId; +TX]~k79Oq
/** Creates a new instance of CountData */ Qt$Q/<8U
public CountBean() {} :|g{gi
public void setCountType(String countTypes){ /~Iy1L#
this.countType=countTypes; '*:YC
} O%I'
public void setCountId(int countIds){ o2L/8q.
this.countId=countIds; 5P4>xv[
} rRW&29A
public String getCountType(){ LY MfoXp
return countType; 2#^[`sFPO
} RK0IkRXQd
public int getCountId(){ E =E
return countId; C-7.Sa
} q0<g#jK
} %rsW:nl
;Baf&xK
CountCache.java -3Ffk:
sXUM,h8$!+
/* |@+
x9|'W
* CountCache.java C`ok{SNtUy
* l"Css~^
* Created on 2007年1月1日, 下午5:01 *\>7@r[%5
* & 3gni4@@
* To change this template, choose Tools | Options and locate the template under R]dB Uu
* the Source Creation and Management node. Right-click the template and choose #q-t!C%E
* Open. You can then make changes to the template in the Source Editor. 6Yklaq5
*/ O/-xkzR*
n\QG-?%Pi
package com.tot.count; ~ rRIWfhb
import java.util.*; 3,GSBiK3}
/** 6Z3v]X
* Gr_I/+<
* @author NXV%j},>
*/ czj[U|eB}=
public class CountCache { R_lNC]b0
public static LinkedList list=new LinkedList(); 49CMRO,T
/** Creates a new instance of CountCache */ =(o$1v/k
public CountCache() {} ve$P=ZuM
public static void add(CountBean cb){ e='3gzz
if(cb!=null){ 4CDmq[AVS[
list.add(cb); k;%}%"EVZ
} dsh}-'>
} Ws=J)2q
} 9:P)@UF
|(w x6H:
CountControl.java &Z9b&P
Dv$xP)./
/* re<"%D
* CountThread.java CxO)d7c
* ).-FuL4Y
* Created on 2007年1月1日, 下午4:57 3M^ /
* C?zC|0
* To change this template, choose Tools | Options and locate the template under :`_wy-}V
* the Source Creation and Management node. Right-click the template and choose 2WKA] l;
* Open. You can then make changes to the template in the Source Editor. j@9A!5<CCk
*/ zj8;ENhEI
\PL92HV
package com.tot.count; ieObo foD
import tot.db.DBUtils; KxY|:-"Tt
import java.sql.*; B64%|
S
/** pxP7yJL`
* L-Z1Xs
* @author X2s=~)`#c
*/ 7^S &g.A
public class CountControl{ 3?2;z+cz*u
private static long lastExecuteTime=0;//上次更新时间 ym-212wl
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 }Za[<t BWS
/** Creates a new instance of CountThread */ [j&>dE
public CountControl() {} .sCo,
public synchronized void executeUpdate(){ +&JF|#FQ`
Connection conn=null; ww=< =
PreparedStatement ps=null; D`Fl*Wc4H
try{ a
"8/y4Y
conn = DBUtils.getConnection(); ~?nPp$^
conn.setAutoCommit(false); ~bgFU
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 7kleBDDT
for(int i=0;i<CountCache.list.size();i++){ &7}-Xvc
CountBean cb=(CountBean)CountCache.list.getFirst(); ='>k|s:
CountCache.list.removeFirst(); -Ndd6O[ a5
ps.setInt(1, cb.getCountId()); w!%Bc]
ps.executeUpdate();⑴ b>G!K)MS3
//ps.addBatch();⑵ *S*;rLH9c
} KrG$W/<tg
//int [] counts = ps.executeBatch();⑶ g(|p/%H
conn.commit(); TqCzpf&&h/
}catch(Exception e){ S__+S7]Nr
e.printStackTrace(); )R,*>-OPJL
} finally{ I 8e{%PK
try{ 4_)@Nq
if(ps!=null) { |7%M:7Q
ps.clearParameters(); "c=\?
ps.close(); s!uewS.
ps=null; zPZy#7/A
} X`[or:cB
}catch(SQLException e){} vA"yy"B+ V
DBUtils.closeConnection(conn); L7C!rS
} WY #pzBA
} -k")#1
public long getLast(){ kx*=1AfU+Y
return lastExecuteTime; KTd4pW?w
} m8#+w0p)
public void run(){ LBbk]I
long now = System.currentTimeMillis(); `UGHk*DL)
if ((now - lastExecuteTime) > executeSep) { >4b-NS/}0
//System.out.print("lastExecuteTime:"+lastExecuteTime); N'3Vt8o,
//System.out.print(" now:"+now+"\n"); |-=^5q5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); E*i <P
lastExecuteTime=now; 2wpLP^9Vr<
executeUpdate(); d 6j'[
} Em %"]B
else{ >@`D@_v
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); j)]mN$Sa:
} rt^<=|Z
} Ks7DoXCvE
} VYMs`d[
//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 Ws{2+G~
5$`ihO?
类写好了,下面是在JSP中如下调用。 R=_
fk
"~> # ;x{
<% lL/|{A|-j
CountBean cb=new CountBean(); -[^aWNqyJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 7`thM/fN
CountCache.add(cb); 3T+#d-\
out.print(CountCache.list.size()+"<br>"); $i7iv
CountControl c=new CountControl(); 8%@7G*
c.run(); Rbm"Qz
out.print(CountCache.list.size()+"<br>"); ~kj1L@gy
%>