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: Q}G
:V`q;g
CountBean.java z.7 UfLV9
_c`Gxt%
/* P4s:wuJ^
* CountData.java 64[j:t=N
* 7pkc*@t
* Created on 2007年1月1日, 下午4:44 n`CmbM@@
* D`Fl*Wc4H
* To change this template, choose Tools | Options and locate the template under u U\UULH0
* the Source Creation and Management node. Right-click the template and choose Q5baY\"9^
* Open. You can then make changes to the template in the Source Editor. pS51fF9
*/ tk ~7>S
mz>"4-]
package com.tot.count; nc([e9_9v
jo+T!CUM'
/** T"3WB o
* ;5oY)1
* @author +>{{91mN
*/ D_'Zucq
public class CountBean { B>gC75
private String countType; ^lbOv}C*
int countId; F)!B%4
/** Creates a new instance of CountData */ sA:0b5_a
public CountBean() {} o:m:9dn
public void setCountType(String countTypes){ Lk`0z
this.countType=countTypes; M7UVL&_z%
} P oC*>R8
public void setCountId(int countIds){ =TU"B-*
this.countId=countIds; 7(ZI]<
} N9_9{M{
public String getCountType(){ DOf[? vbu
return countType; !Il<'+ ^
} )4 "G1R`3
public int getCountId(){ D{\hPv
return countId; ASPfzW2
} pZF`+642
} lZ'NLbK
km.xy_v
CountCache.java v"\Q/5p
o)srE5
/* DL<r2h
* CountCache.java 4,UvTw*2z
* Bz]j&`
* Created on 2007年1月1日, 下午5:01 9qW^@5
m
* *=)%T(^
* To change this template, choose Tools | Options and locate the template under yn"8Ma*
* the Source Creation and Management node. Right-click the template and choose eCdMDSFO3
* Open. You can then make changes to the template in the Source Editor. 3<#4
*/ ;IE|XR(
NmVc2V]I
package com.tot.count; *b~$|H-\
import java.util.*; DCFYpkR%
/** J!~?}Fq/z
* OlQ7Yi>
* @author =l?5!f9
*/ 2Q0fgH2
public class CountCache { LeXuTd
public static LinkedList list=new LinkedList(); 67%o83\
/** Creates a new instance of CountCache */ +Z#lf
public CountCache() {} 89?AcZ.D
public static void add(CountBean cb){ ?HAWw'QW
if(cb!=null){ |'Z6M];8t
list.add(cb); ig)rK<@*[
} -"#;U`.oh7
} _.yBX\tf[
} =X]$J@j
|?i-y3N
CountControl.java pd/{yX M
`pOiv&>
/* =; `+^
* CountThread.java c5nl!0XX
* eBlVb*nmq
* Created on 2007年1月1日, 下午4:57 CZuV{Oh}?
* L1
O\PEeT
* To change this template, choose Tools | Options and locate the template under P]bI".A8
* the Source Creation and Management node. Right-click the template and choose &FW|O(]
* Open. You can then make changes to the template in the Source Editor. *C}vy`X
*/ 1-Sc@WXd
f@]4udc e
package com.tot.count; 'OK)[\
import tot.db.DBUtils; ix [aS
import java.sql.*; %\Z{~(&-v
/** uF/l,[0v
* #EgFB}>1
* @author 2*ZB[5_V
*/ %nSLe~b
public class CountControl{ S{XV{o
private static long lastExecuteTime=0;//上次更新时间 LhUrVydL
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @Q
8E)k@
/** Creates a new instance of CountThread */ 049E#[<Q"
public CountControl() {} \,+act"v
public synchronized void executeUpdate(){ Dh*Uv,
Connection conn=null; tl !o;`W
PreparedStatement ps=null; aq@/sMn
try{ `
zeZ7:
conn = DBUtils.getConnection(); }YfM<
conn.setAutoCommit(false); TGl It<&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); rd vq(\A
for(int i=0;i<CountCache.list.size();i++){ Tky\W%Ag
CountBean cb=(CountBean)CountCache.list.getFirst(); /\q1,}M
CountCache.list.removeFirst(); |kB1>$
ps.setInt(1, cb.getCountId()); WyF1Fw
ps.executeUpdate();⑴ /=).)<&|R
//ps.addBatch();⑵ }lvD 5
} FFQ=<(Ki
//int [] counts = ps.executeBatch();⑶ xPl+
rsU
conn.commit(); =$`EB
}catch(Exception e){ :<=A1>&8
e.printStackTrace(); .v?Ir)
} finally{ \#?n'qyj
try{ !yI , ~`Z
if(ps!=null) { 7^>UUdk(
ps.clearParameters(); z<YOA
ps.close(); 87.b7 b.
ps=null; X"0n*UTF,
} 5ztHar~f
}catch(SQLException e){} F@~zVu3'
DBUtils.closeConnection(conn); 6p|*H?|It
} T:p,!?kc7
} Ztu _UlGC
public long getLast(){ 8+5z -vd
return lastExecuteTime; By%mJ%$~
} WqlX'tA
public void run(){ ky0Fm
W
long now = System.currentTimeMillis(); z~i=\/~tZ
if ((now - lastExecuteTime) > executeSep) { Yx>y(Whu.
//System.out.print("lastExecuteTime:"+lastExecuteTime); 16Ym*kWIps
//System.out.print(" now:"+now+"\n"); V<A_c^unO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); EdbLAagI6
lastExecuteTime=now; C]59@z;+bN
executeUpdate(); E2+x?Sc+
} ^@5#jS2
else{ I
CCmE#n
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); E`]lr[
}
KV v0bE
}
>G(M&
} J\VG/)E
//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 ^LO=&Cq
{y-7xg~}
类写好了,下面是在JSP中如下调用。 f_y+B]?'M
G9"2h
\
<% u2%/</]h
CountBean cb=new CountBean(); MY1s
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); XaOq &7
CountCache.add(cb); ig(dGKD\=9
out.print(CountCache.list.size()+"<br>"); Ss ;C1:
CountControl c=new CountControl(); cK6M8:KW
c.run(); ZU\TA|
out.print(CountCache.list.size()+"<br>"); =
zJY5@^'7
%>