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: y o
|"-
E ) iEWc
CountBean.java |SfmQ;
9et%Hn.K'
/* N5\]VCX
* CountData.java @XRN#_{
* 7C"&f *lEi
* Created on 2007年1月1日, 下午4:44 J52- qR/
* n~|sMpd,M1
* To change this template, choose Tools | Options and locate the template under 9C2DW,?
* the Source Creation and Management node. Right-click the template and choose 896oz>
* Open. You can then make changes to the template in the Source Editor. N(@B3%H2/J
*/ #`(-Oj2hH
|E#+X
package com.tot.count; C}>Pn{wY9
P>s3Rh3:
/** sF+Bu'9A
* b6y/o48
* @author y2:~_MD
*/ eW>Y*l%B
public class CountBean { a8wQ,
private String countType; e qzmEg
int countId; OX!<{9o
/** Creates a new instance of CountData */ vv%
o+r-t
public CountBean() {} 1?}5.*j<
public void setCountType(String countTypes){ u|}p3-z|Y
this.countType=countTypes; RC>79e/u<
} G&2`c\u{
public void setCountId(int countIds){ -SGoE=
this.countId=countIds; o,yP9~8\
} 1FfSqd
public String getCountType(){ :497]c3#5C
return countType; (_aM26s
} gJUawK
public int getCountId(){
ndCHWhi
return countId; &W@#pG
} WMw^zq?hd@
} aUTXg60l*
7)U08"
CountCache.java 'W2B**}
?7]UbtW[
/* / 80Q
* CountCache.java ;Or]x?-
* q{:]D(
* Created on 2007年1月1日, 下午5:01 pDloew
* ,6iXl ch
* To change this template, choose Tools | Options and locate the template under Je1'0h9d
* the Source Creation and Management node. Right-click the template and choose Q?uHdmY*X
* Open. You can then make changes to the template in the Source Editor. K#>@T<
*/ Y_SB3 $])
}Jr!aM'
package com.tot.count; v:7_ZD6kR
import java.util.*; k=D}i\F8
/** ~As/cd>9
* ,N`cH\
* @author e*?@6E
*/ A`nw(f_/
public class CountCache { {`>;I
public static LinkedList list=new LinkedList(); z 7
s&7)a
/** Creates a new instance of CountCache */ LZ 3PQL
public CountCache() {} alV{| Vf[6
public static void add(CountBean cb){ abgAUg)
if(cb!=null){ u>y/<9]q8
list.add(cb); dum(T
} @}+F4Xh,L
} snm1EPj
} ];63QJU
Mr6 q7
CountControl.java /ho7O/aAa
YM<F7tp4
/* !bGMVw6_
* CountThread.java qvN`46c
* >5c38D7k)
* Created on 2007年1月1日, 下午4:57 'irHpN6n
* 7~
=r9-&G
* To change this template, choose Tools | Options and locate the template under p/WE[8U
* the Source Creation and Management node. Right-click the template and choose mDX
UF~G[
* Open. You can then make changes to the template in the Source Editor. f~-qjEWm
*/ agUdPl$e\
4E0 Y=
package com.tot.count; l1uv]t <
import tot.db.DBUtils; t}x^*I$*
import java.sql.*; G'c6%;0)
/** W%_Cda5,
* h4geoC_W2
* @author $dkkgsw7
*/ + )lkHv$R
public class CountControl{ v~`'!N8
private static long lastExecuteTime=0;//上次更新时间 Qt(4N!j
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :vo#(
/** Creates a new instance of CountThread */ g),t
public CountControl() {} PGNH<E)
public synchronized void executeUpdate(){ ay`A Gr
Connection conn=null; .0b4"0~T6
PreparedStatement ps=null; ?
e<D +
try{ 8;GuJP\
conn = DBUtils.getConnection(); MG(qQ#;j/
conn.setAutoCommit(false); cj@ar^=`K
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Zy&?.d[z
for(int i=0;i<CountCache.list.size();i++){ 8h'*[-]70u
CountBean cb=(CountBean)CountCache.list.getFirst(); Q8?:L<A
CountCache.list.removeFirst(); ^\3r}kJ0Lp
ps.setInt(1, cb.getCountId()); 7AuzGA0y
ps.executeUpdate();⑴ )7;E,m<:tO
//ps.addBatch();⑵ gq~6jf>
} 7I;A5f
//int [] counts = ps.executeBatch();⑶ w6<zPrA
conn.commit(); F$nc9x[S
}catch(Exception e){ @0&KM|+
e.printStackTrace(); ?v@pB>NZ
} finally{ "Kc1@EX=
try{ i=AQ1X\s
if(ps!=null) { a*bAf'=
ps.clearParameters(); Su*f`~G];
ps.close(); 3\E G
ps=null; >NMq^J'/
} -W'T3_
}catch(SQLException e){} cZl/8?dj}
DBUtils.closeConnection(conn); AoFxh o
} {No
Y`j5S
} ukwO%JAr
public long getLast(){ `w
K6B5>
return lastExecuteTime; s~n@|m9k
} ^udl&>
public void run(){ \Jm^XXgS
long now = System.currentTimeMillis(); 4ZCD@C
if ((now - lastExecuteTime) > executeSep) { i&Xjbcbp
//System.out.print("lastExecuteTime:"+lastExecuteTime); n1PV/ Z
//System.out.print(" now:"+now+"\n"); AEE&{_[S
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }zyh!
lastExecuteTime=now; hzV= 7
executeUpdate(); )=5,S~IT
} bD4aSubN
else{ Dt glPo_(
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); HMl
M!Xk?
} H}PZJf_E
}
lqZUU92;
} FfpP<(4
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 eiJ~1HX)
7(plHW|
类写好了,下面是在JSP中如下调用。 i(an]%'v
QUKv :;
<% Ac8t>;=&
CountBean cb=new CountBean(); Mi:i1i
cdn
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v18OUPPX
CountCache.add(cb); gH:+$FA
out.print(CountCache.list.size()+"<br>"); $q 9dkt
CountControl c=new CountControl(); $b`~K MO
c.run(); y1_z(L;I
out.print(CountCache.list.size()+"<br>"); v&r\Z @%
%>