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: )l7XZ_gw'
^#HaH
CountBean.java 7k(}U_v
!6KX^j-
/* p~ b4TRvA6
* CountData.java %S`&R5
* 0%ul6LvM
* Created on 2007年1月1日, 下午4:44 <RY =y?%z
* ;
oyV8P$
* To change this template, choose Tools | Options and locate the template under |ia5Mr"t
* the Source Creation and Management node. Right-click the template and choose eV[{c %wN:
* Open. You can then make changes to the template in the Source Editor. @C)s4{V
*/ jE\G_>
Alxf;[s
package com.tot.count; BNfj0e 5b
V\cbIx(Z^
/** HwUaaK
* ?woL17Gt
* @author ppyy0E^M
*/ ^M'(/O1
public class CountBean { {821e&r
private String countType; ] pn
U"
int countId; |U%NPw5
/** Creates a new instance of CountData */ x>yqEdR=o
public CountBean() {} %Mda<3P
public void setCountType(String countTypes){ (S~kyU!)0
this.countType=countTypes; cx\E40WD
} r&{8/ 5"
public void setCountId(int countIds){ nTeA=0 4
this.countId=countIds; @dWA1tM
} DYf QlA
public String getCountType(){ :_8K8Sa
return countType; ;m]V12
} ZcN0:xU
public int getCountId(){ C/k#gLF`
return countId; Kh]es,$D
} #a e@VedM
} q+?&w'8
WqeWjI.2
CountCache.java >C0B!MT?3%
16iTE-J_
/* K4Q{U@ZJ
* CountCache.java >w3C
Ku<
* gP%<<yl
* Created on 2007年1月1日, 下午5:01 3:,%>#"
* )Te\6qM
* To change this template, choose Tools | Options and locate the template under ~7:q+\
* the Source Creation and Management node. Right-click the template and choose `<YMkp[
* Open. You can then make changes to the template in the Source Editor. QVT0.GzR
*/ |! 9~
w
<r*&
package com.tot.count; +(+lbCW/
import java.util.*; xV>
.]
/** ht-'O"d:
* REh"/d
* @author 8W&1"h`
*/ K*@?BE
public class CountCache { 56Wh<i3
public static LinkedList list=new LinkedList(); n!4}Hwz!
/** Creates a new instance of CountCache */ n{?Du
public CountCache() {} Ne
u$SP
public static void add(CountBean cb){ -'&l!23a~
if(cb!=null){ [<@L`ki
list.add(cb); V^s, 3C
} .\b.l@O<Z
} b `P6Ox3
} 7!M; ?Y
gq('8*S
CountControl.java ?p{-Yp*h
OLG)D#m(4/
/* rmjuNy=(
* CountThread.java i+`8$uz
* ,a5q62)q
* Created on 2007年1月1日, 下午4:57 nAP*w6m0j
* K_MEd1l
* To change this template, choose Tools | Options and locate the template under [vu;B4^"
* the Source Creation and Management node. Right-click the template and choose {QEvc
* Open. You can then make changes to the template in the Source Editor. +Z"Wa0wA
*/ dpW`e>o
ui?@:=
package com.tot.count; ]-wyZ +a
import tot.db.DBUtils; @WazSL;N
import java.sql.*; (Aw@}!
/** \; XJ$~>
* nAQ[
-NbW,
* @author 6nA9r5Ghv
*/ o "r
public class CountControl{ 3cJ'tRsp<
private static long lastExecuteTime=0;//上次更新时间 #?Ix6 {R
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,zjz "7'
/** Creates a new instance of CountThread */ Y~Uf2(7b5
public CountControl() {} /
B!j`UK
public synchronized void executeUpdate(){ $?ss5:
S
Connection conn=null; ?8753{wk
PreparedStatement ps=null; ~=yU%5 s@
try{ }oD^tU IK
conn = DBUtils.getConnection(); 61_PSScSY
conn.setAutoCommit(false); 6GuTd
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); MgiW9@_(
for(int i=0;i<CountCache.list.size();i++){ ^C
K!=oO
CountBean cb=(CountBean)CountCache.list.getFirst(); |21VOPBS
CountCache.list.removeFirst(); DlzL(p@r
ps.setInt(1, cb.getCountId()); X}GX6qAdt
ps.executeUpdate();⑴ pauO_'j_1p
//ps.addBatch();⑵ zeGWM,!
} 1Ne;U/
//int [] counts = ps.executeBatch();⑶ xjp0w7L)J
conn.commit(); IfH/~EtX
}catch(Exception e){ W2<'b05
e.printStackTrace(); %0&,_jM/9
} finally{ 5]G%MB/|$
try{ )7NK+k
if(ps!=null) { VK/L}^=GOO
ps.clearParameters(); c6b51)sQ"
ps.close(); X[/7vSqZ@w
ps=null; hGKQK
^bn
} Wt%Wpb8
}catch(SQLException e){} n%WjU)<
DBUtils.closeConnection(conn); I?1BGaAA
} blomB2vQ
} o5]-Kuw`
public long getLast(){ ea{zL
return lastExecuteTime; ]R~hzo
} {JdXn
public void run(){ +/_XSo
long now = System.currentTimeMillis(); iklZ[G%A0
if ((now - lastExecuteTime) > executeSep) { l>|scs;TI
//System.out.print("lastExecuteTime:"+lastExecuteTime); |7K>`
//System.out.print(" now:"+now+"\n"); wKJ|;o4;L
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); _ow7E\70
lastExecuteTime=now; ByE@4+9
executeUpdate(); [$} \Gv
} A#`$#CO
else{ e6*,MnqBh
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); |Fx *,91
} (0@b4}Z
} I>8_gp\1
} OeGLMDw
//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 F^.]g@g.|
U
`lp56
类写好了,下面是在JSP中如下调用。 BW)@.!C
jcC"vr'u|
<% ) M8,Tv*~
CountBean cb=new CountBean(); %4R1rUrgt|
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); id,' + <
CountCache.add(cb); C`ZU.|R
out.print(CountCache.list.size()+"<br>"); jBEW("4R
CountControl c=new CountControl(); o]I8Ghk>/z
c.run(); vMY!Z1.*
out.print(CountCache.list.size()+"<br>"); CY=lN5!J
%>